Professor Françoise Barré-Sinoussi - Solvay Institutes

REPORT 2009

REPORT 2009

Ernest Solvay regarded science, in its various
forms, as the key that would open
the door to a richer life for man. He had
remarked once: “Among the new paths
of science, I undertook to follow three directions;
three problems which in my view,
form a certain unity. First, a general problem
of physics – the constitution of matter
in time and space; then a problem of
physiology – the mechanism of life from its
most humble manifestations up to the phenomena
of thought processes; and finally,
the third one, a problem complementary
to the first two – the evolution of the individual
and that of social groups.
Jacques Solvay
Opening address
XVIII th Solvay Conference on Physics (1982)
I have always regarded the institution
of the Solvay Conferences in Physics
and Chemistry as of the highest value to
science…
Ernest Rutherford
Nobel Laureate in Chemistry (1908)
1 st Solvay Conference on Chemistry (1922)

The International Institutes for
Physics and Chemistry,
founded by Ernest Solvay,
acknowledge with gratitude
the generous support of
the Solvay family
Solvay S.A. - N.V
the “Université Libre
de Bruxelles”
the
“Loterie Nationale”-
“Nationale Loterij”
the “Vrije
Universiteit Brussel”
the “Communauté
Française
de Belgique”
the “Vlaamse
Regering”
the “Fondation
David et Alice
Van Buuren”
the Hotel Metropole
“Politique Scientifique
Fédérale - Federaal
Wetenschapbeleid”

Contents
A word from the Director 10
General Information
o Board of Directors 14
o Scientific Committee for Physics 16
o Scientific Committee for Chemistry 17
o International Advisory Committee 18
o Local Scientific Committee 18
o Honorary Members 19
Solvay Public Event and Solvay Awards
Françoise Barré-Sinoussi, 2008 Nobel Laureate in Medicine,
“VIH/SIDA, une aventure scientifique et humaine en réponse
à une épidémie émergente” 35
International Solvay Chairs 45
o Solvay Chair in Chemistry: Professor Alexander S. Mikhailov
(Department of Physical Chemistry, Fritz Haber Institute
of the Max Planck Society, Berlin, Germany) 47
o Solvay Chair in Physics: Professor Valery Rubakov
(Institute for Nuclear Research of the Russian Academy
of Sciences, Moscow, Russia) 57
Workshops and Schools organized by the Institutes 63
o Workshop on “Sparsity, learning and computation”
organized by Ingrid Daubechies (VUB & Princeton) and
Christine De Mol (ULB) 75
o Workshop on “Cosmological Frontiers in Fundamental
Physics” organized by Ben Craps (VUB), Thomas Hertog
(Paris 7), Peter Tinyakov (ULB) and Michel Tytgat (ULB) 91
o Workshop on “Chemo-hydrodynamic patterns and
instabilities” organized by Anne De Wit (ULB) 101
o Modave Summer School in Mathematicals Physics 101
Doctoral School 107
8

Contents
Colloquia 113
Institutional Collaborations 123
o Centro de Estudios Científicos (CECS), Chile 124
o Lebedev Physical Institute, Russia 125
Conference sponsored by the Institutes 129
o Workshop on “Nonlinear Elliptic PDEs” organized
by the ULB, with support from the Institutes 130
5 th Flemish Space Days/ Vijfde Vlaamse Ruimtevaartdagen
organized by the Flemish Space Industries 135
Seminars 139
Research on Gravitation, Strings and Cosmology 145
o Researchers 146
o Research Summary 148
o Research Interests of some Members 150
o Appraisals & Prizes - Theses defended in 2009 154
o Invited Talks at Conferences, Seminars and Schools 158
o List of Publications 164
Research carried out in the group of the Deputy Director 169
o Members 170
o Research Summary 170
o Invited Talks at Conferences, Seminars and Schools 172
o List of Pubications 173
Report of the International Advisory Committee 169
Appendix: Outreach 175
o Newspapers and Edition 176
o Colophon 184
9

A word from the Director
This report reviews the activities
organized or supported by the
International Solvay Institutes during
the year 2009. These activities, to
which hundreds of scientists took
part, are detailed in the corresponding
sections. Only the highlights
of the year will be mentioned
in this foreword.
Since 2004, many new programs
have been launched at the Institutes:
workshop series, Solvay Chairs in
Physics and Chemistry, International
Doctoral School in theoretical
physics, Public Lectures, Colloquia.
In addition, the Solvay Conferences
resumed their original pace of being
organized every three years
along the unique scientific lines initiated
by Lorentz. After 5 years of
running of these new programs,
it was regarded as healthy and
necessary to have an external
evaluation of our activities by an
International Advisory Committee
(“Visiting Committee”) composed
of outstanding scientists. Their first
visit took place in March of 2009.
The conclusions of the Committee
are extremely positive. Their report
is reproduced in its entirety at the
end of this volume. Its final lines
read: “The overall impression that
the committee has obtained is that
the Solvay Institutes are run in a
most impressive and competent
way. It is remarkable that […] the
Institutes have been re-established
as world-leading institutions so
swiftly, and the committee can only
congratulate Belgium and the scientific
communities in physics and
chemistry to this achievement.”
This provides an enormous encouragement
for the future. The report
makes also suggestions for new
scientific directions and for giving a
more stable basis to the funding of
the Institutes. The anniversary year
2011 will provide a splendid opportunity
to try to implement these
suggestions and many projects are
already in preparation. We are
grateful to the International Advisory
Committee for the time that they
spent both in the evaluation on-site
of our activities and in the careful
preparation of their report.
The International Solvay Chairs in
Physics and Chemistry, respectively
created in 2006 and 2008, are still
young but have already become a
well-established tradition, which is
much appreciated by the scientific
community.
The 2009 Solvay Professor in
Chemistry was Professor Alexander
Mikhailov, Director at the Fritz
Haber Institute of the Max Planck
Society in Berlin (Germany). Professor
Mikhailov is renowned internationally
for his remarkable contributions
to various fields of physical
chemistry. His teaching took place
in the Spring and was included
10

in the master training of Brussels students in
chemistry. He gave a fascinating inaugural
lecture “From Structure to Function: Chemistry
in Transition” in which he developed modern
and original points of view on chemistry.
The 2009 Solvay Chair in Physics was
held by Professor Valery Rubakov, from the
Institute for Nuclear Research of the Russian
Academy of Sciences in Moscow (Russia).
Professor Rubakov is a leading figure in theoretical
physics and pioneered many new approaches
to cosmology and particle physics.
His inaugural lecture: “Particle physics and
cosmology: towards understanding the
Universe” addressed the current challenges
faced in the field. It was followed by a course
of lectures which was included in the doctoral
training of the international Amsterdam-
Brussels-Paris doctoral school on “Quantum
FieldTheory, Strings and Gravity”.
The International Solvay Institutes have also
organized or sponsored workshops and conferences
on themes ranging from mathematics
to cosmology and physical chemistry.
We have also supported two graduate
schools as training through research is one of
our goals. Finally, our colloquium series has
been ongoing with the same vitality.
The present report describes also the research
carried by the scientists affiliated with
the Institutes. The main area of investigation is
the understanding of gravity, which remains
the most mysterious force in the universe.
On the financial side, strict management
practices have enabled us to use part of the
revenues from the endowment to continue reimbursing
our debt from the past. I am grateful
to our treasurer, Professor Bingen, for his
efficient support in enforcing these strict rules.
A word General from the Information Director
Another highlight of 2009 was the joint
organization with the Solvay Company
of a public event in October. The Institutes
regard the popularization of science among
the general public as one of their missions.
Professor Françoise Barré-Sinoussi, 2008
Nobel Laureate in Medecine, gave a captivating
lecture on “VIH/SIDA, une aventure
scientifique et humaine en réponse à une
épidémie émergente”. The lecture, which
enjoyed simultaneous interpretations into
Dutch and English, was attended by many
young people and was a notable success.
The event was coupled with the Solvay
Award Ceremony, delivered by the Solvay
Company to brilliant young researchers in
physics and chemistry.
Finally, I would also like to thank all the sponsors
of the Solvay Institutes. These are the
“Université Libre de Bruxelles”, the “Vrije
Universiteit Brussel”, the Solvay Company,
the Belgian National Lottery, the “Communauté
Française de Belgique”, the “Vlaamse
Regering”, the Belgian Science Policy, the
David & Alice Van Buuren Foundation, the
“Hôtel Métropole” and last but not least, the
Solvay family who is unfailingly supporting
the Institutes since their very beginning.
The extraordinary dedication and efficiency
of the entire staff working at the Institutes is
also gratefully acknowledged.
Marc Henneaux
11

Stephen Hawking, Harold Kroto and Solvay Awards
General Information
General Information
13

General Information
Board of Directors
Members
Mr Solvay
Professor Franz Bingen
Emeritus - Professor VUB
Professor Rosette S’Jegers
Dean VUB and Professor VUB
President
Vice-President and Treasurer
Secretary
Professor Françoise Thys-Clément
Honorary Rector and Professor ULB
Mr Philippe Busquin
European Deputy and Former European Commissioner
Baron Daniel Janssen
Honorary Chairman of the Board of Directors of Solvay S.A.
Mr Jean-Marie Solvay
Member of the Board of Directors of Solvay S.A.
Mr Eddy Van Gelder
President of the Administrative Board of the VUB
Professor Jean-Louis Vanherweghem
President of the Administrative Board of the ULB
Honorary Members
Professor Irina Veretennicoff
Professor VUB
Baron Jaumotte
Honorary Rector and Honorary President ULB
Honorary Director
Mr Jean-Marie Piret
Attorney General of the Supreme Court of Appeal
and Honorary Principal Private Secretary to the King
14

Guests
Professor Marc Henneaux
Professor ULB
Director
General Information
Professor Franklin Lambert
Professor VUB
Professor Anne De Wit
Professor ULB
Professor Alexander Sevrin
Professor VUB
Deputy Director
Scientific Secretary of the Committee
for Chemistry
Scientific Secretary of the Committee
for Physics
Professor Hervé Hasquin
Permanent Secretary of the Royal Academy of Sciences, Letters and Fine Arts of Belgium
Professor Niceas Schamp
Permanent Secretary of the Royal Flemish Academy of Belgium for Science and the Arts
Management and Staff
Director
Deputy Director
Assistants to the Director
Administrative Assistants
Accountant
Professor Marc Henneaux (ULB)
Professor Franklin Lambert (VUB)
Professor Anne De Wit (ULB)
Professor Glenn Barnich (ULB)
Professor Ben Craps (VUB)
Ms Dominique Bogaerts
Ms Isabelle Juif
Ms Chantal Verrier
Postal address: International Solvay Institutes, Campus Plaine ULB / CP 231, Bd du Triomphe, B-1050 Brussels, Belgium
Delivery address: International Solvay Institutes, Campus Plaine ULB / Access 2, Bd de la Plaine, Building NO, 5 th Floor
Office N105A, B-1050 Brussels, Belgium
Tel: + 32 2 650 54 23 (Ms Juif) or + 32 2 650 55 42 (Ms Bogaerts) Fax: + 32 2 650 50 28
Emails: dobogaer@ulb.ac.be, Isabelle.Juif@ulb.ac.be Website: http://www.solvayinstitutes.be
15

General Information
Scientific Committee for Physics
Members are appointed for a 6-year period term, renewable once.
Chair
Members
Professor David GROSS, Nobel Prize 2004, Kavli
Institute for Theoretical Physics, Santa Barbara, USA
Professor Fortunato Tito ARECCHI, Università di Firenze
and INOA, Italy (1 July 2004 - 30 June 2010, Second Term)
Professor Jocelyn BELL BURNELL, Oxford University, UK
(1 July 2004 - 30 June 2010, First Term)
Professor Steven CHU, Nobel Prize 1997, Stanford
University, USA (1 January 2008 - 31 December 2013, First Term)
Professor Claude COHEN-TANNOUDJI, Nobel Prize
1997, Ecole Normale Supérieure, Paris, France
(1 July 2004 - 30 June 2010, Second Term)
Professor Ludwig FADDEEV, V.A Steklov Mathematical
Institute, Saint-Petersburg, Russia
(1 July 2004 - 30 June 2010, Second Term)
Professor Gerard ’t HOOFT, Nobel Prize 1999,
Spinoza Instituut, Utrecht, the Netherlands
(1 July 2004 - 30 June 2010, Second Term)
Professor Giorgio PARISI, Università La Sapienza,
Roma, Italy (1 January 2008 - 31 December 2013, First Term)
Professor Pierre RAMOND, University of Florida,
Gainesville, USA (1 July 2004 - 30 June 2010, First Term)
Professor Klaus VON KLITZING, Nobel Prize 1985,
Max-Planck-Institut, Stuttgart, Germany
(1 July 2004 - 30 June 2010, First Term)
Scientific Secretary
Professor Alexander SEVRIN, Vrije Universiteit Brussel,
Belgium
16

Scientific Committee for Chemistry
Members are appointed for a 6-year period term, renewable once.
Chair
Professor Stuart RICE, University of Chicago, USA
General Information
Members Professor Manfred EIGEN, Nobel Prize 1967,
Max-Planck Institut, Göttingen, Germany
(1 June 2005 - 31 May 2011, Second Term)
Professor Graham FLEMING, University of Berkeley,
USA (1 June 2005 - 31 May 2011, First Term)
Professor Harold W. KROTO, Nobel Prize 1996, University
of Sussex, Brighton, UK (1 June 2005 - 31 May 2011, First Term)
Professor Jean-Marie LEHN, Nobel Prize 1987, Collège
de France, Paris, France (1 June 2005 - 31 May 2011, Second Term)
Professor Henk N.W. LEKKERKERKER, Utrecht Universiteit,
the Netherlands (1 June 2005 - 31 May 2011, First Term)
Professor Mario J. MOLINA, Nobel Prize 1995,
Massachusetts Institute of Technology, Cambridge,
USA (1 June 2005 - 31 May 2011, Second Term)
Professor K.C. NICOLAOU, University of California,
San Diego, USA (1 June 2005 - 31 May 2011, First Term)
Professor Kurt WÜTHRICH, Nobel Prize 2002, Institut für
Molekularbiologie und Biophysik, Zurich, Switzerland
(1 June 2005 - 31 May 2011, First Term)
Scientific Secretary
Professor Anne DE WIT, Université Libre de
Bruxelles, Belgium
17

General Information
International Advisory Committee
Members are appointed for a 6-year period term, renewable once.
Chair
Professor Lars BRINK, Chalmers University of Technology,
Göteborg, Sweden (1 June 2008 - 31 may 2014)
Members Professor Leticia CUGLIANDOLO, Université Paris 6,
France (1 June 2008 - 31 may 2014)
Professor Hermann NICOLAI, Max-Planck-Institut für
Gravitationsphysik (Albert-Einstein-Institut), Potsdam,
Germany (1 June 2008 - 31 may 2014)
Professor Jacques PROST, École Supérieure de Physique
et Chimie Industrielles (ESPCI), Paris, France
(1 June 2008 - 31 may 2014)
Professor Hirosi OOGURI, Caltech, Pasadena, USA and
Tokyo University, Japan (1 June 2008 - 31 may 2014)
Professor Gunnar VON HEIJNE, Stockholm University,
Sweden (1 June 2008 - 31 may 2014)
Local Scientific Committee
Chair
Members
Professor Marc HENNEAUX (ULB)
Professor Ben CRAPS (VUB)
Professor Anne DE WIT (ULB)
Professor Pierre GASPARD (ULB)
Professor Paul GEERLINGS (VUB)
Professor Albert GOLDBETER (ULB)
Professor Alexander SEVRIN (VUB)
18

Honorary Members
Professor Anatole ABRAGAM, Collège de France, Paris, France
Professor Robert BROUT, Université Libre de Bruxelles, Belgium
General Information
Professor Claudio BUNSTER, Centro de Estudios Científicos,
Valdivia, Chile
Professor François ENGLERT, Université Libre de Bruxelles, Belgium
Professor Ludwig FADDEEV, V.A. Steklov Mathematical
Institute, St Petersburg, Russia
Professor Ephraïm KATCHALSKY, Weizmann Institute,
Rehovot, Israel
Professor I.M. KHALATNIKOFF, Landau Institute of
Theoretical Physics, Moscow, Russia
Professor William LIPSCOMB, Nobel Prize 1976,
Harvard University, Cambridge, USA
Professor Victor P. MASLOV, Moscow State University, Russia
Professor Victor A. SADOVNICHY, Moscow State University,
Russia
Professor Roald SAGDEEV, University of Maryland,
College Park, USA
Professor E.C.G. SUDARSHAN, University of Texas,
Austin, USA
Professor Morikazu TODA, Tokyo University of Education,
Japan
Professor Chen Ning YANG, Nobel Prize 1957, Chinese
University Hong Kong & Tsingha University, Beijing, China
19

Images from the Quantum World
Solvay Public Event
&
Solvay Awards
4 October 2009
Solvay Public Event & Solvay Awards
21

Solvay Public Event & Solvay Awards
SOLVAY PUBLIC LECTURE
Sunday 4 October 2009
FLAGEY - STUDIO 4 at 3:30pm
Professor Françoise Barré-Sinoussi
Institut Pasteur, Paris
2008 Nobel Prize in Medicine
”VIH/SIDA, une aventure scientifique et humaine
en réponse à une épidémie émergente”
During the event, a short Solvay Awards ceremony will take place
Simultaanvertaling is voorzien
naar het Nederlands.
Simultaneous interpretation into English.
Free entrance but registration is requested.
Registration, information and programme
on www.solvayinstitutes.be/4oct09.html
© : Institut Pasteur
The event is co-organized with
Sponsors
Avec le soutien de la Ministre de l’Enseignement supérieur et de la Recherche scientifique.
Dit project wordt ondersteund binnen het Actieplan Wetenschapscommunicatie, een initiatief van de Vlaamse Regering.
Designe: info@imagedemarc.be
22

Françoise Barré-Sinoussi, 2008 Nobel Laureate in Medicine
“VIH/SIDA, une aventure scientifique et humaine en
réponse à une épidémie émergente”
The 2009 Solvay public event took place on
October 4, 2009 at the Flagey Building.
The lecturer was 2008 Nobel Laureate in Medecine
Françoise Barré-Sinoussi, from the Institut
Pasteur in Paris. Her lecture « VIH/SIDA, une
aventure scientifique et humaine en réponse à
une épidémie émergente », was simultaneously
interpreted into Dutch and English.
In this crystal-clear talk, she described the structure
and properties of the VIH virus and
its infection mechanisms, as well as the scientific
challenges for developing a vaccine.
She also addressed the means to fight the
AIDS decease through prevention and treatment.
Page 1 / 3
In the spirit of the Solvay public lectures whose
aim is to boost the interest for science, the talk
by Professor Barré-Sinoussi was preceded by
a short Solvay award ceremony during which
students in physics, chemistry and engineering
at the ULB and the VUB who had been distinguished
for their work were celebrated.
The event was attended by more than 350 persons
who had the opportunity to ask questions
and discuss with the speaker after the lecture.
Solvay Public Event & Solvay Awards
PR FORCE NV
INSTITUT SOLVAY
24599
Page 1 / 2
©AuxiPress s.a./n.v.
©AuxiPress s.a./n.v.
23

Solvay Public Event & Solvay Awards
Solvay Public Lectures:
background
Supporting frontier research at the highest level
in physics and chemistry is the main mission
of the Solvay Institutes. This is not their only
mission. It is also the responsibility of scientists
to inform society on the latest developments in
science. For this reason, the Institutes committed
The Solvay Institutes organize one public lecture
per year. The 2009 Public Event was the 6 th one
in the series. The Solvay Institutes have been fortunate
each time to greet exceptional scientists
who gave fascinating talks.
Although the research carried at the Solvay
Institutes is focused on physics and chemistry,
the Solvay public lectures are organized on
broader subjects covering all fields of sciences.
There are various reasons behind this choice.
One reason is that the frontiers between the
scientific disciplines are not clear cut.
To take an example appropriate to the theme of
the 2009 public lecture, was Pasteur a physicist,
a chemist, a biologist or a physician? He contributed
to crystallography, he understood fermentation
and refuted spontaneous generation, and
he made major contributions to virology and
immunology.
But there is another reason for being broad in
the choice of subjects of the public lectures. It is
to show that the men and women who pursue
themselves in 2004 to periodically organize
public events during which the best researchers
would deliver popular lectures on their recent
work.
Informing the general public about the current
scientific developments and discoveries can also
arouse enthusiasm for science and create new
vocations among the young generations.
Indeed, it is more than ever needed that the
young generations embrace scientific careers to
solve the numerous challenges that our contemporary
society faces. The decrease in the number
of students in faculties of sciences is without
doubt a great source of concern.
scientific research share the same passion,
are driven by the same desire to understand
fundamental questions about Nature, have the
same emotions when making discoveries, be it
in physics, chemistry, mathematics, biology or
medicine.
24

Françoise Barré-Sinoussi, 2008 Nobel Laureate in Medicine
The 2009 Solvay Lecturer
Professor Françoise Barré-Sinoussi started
her career at the Pasteur Institute in Paris
where her research focused on the retroviruses
(a particular group of viruses). She
co-discovered the human immunodeficiency
virus (HIV) in 1983, a discovery for which
she received the Nobel Prize in Medicine in
2008.
She has worked on the impact of the innate
defences of the host in controlling HIV/AIDS
as well as mother-to-child transmission. She currently carries research on the development of
a vaccine against AIDS.
Professor Barré-Sinoussi also leads active campaigns against that decease in many developing
countries, where she has initiated multidisciplinary networks dedicated to prevention,
clinical care, and treatment.
She has been elected in 2009 Member of the French Academy of Sciences. In 2010, she
will receive an Honorary Degree from the Université Libre de Bruxelles.
It was a great honor for the International Solvay Institutes that she accepted their invitation to
give the 2009 Solvay Public Lecture, in spite of an extremely tight schedule.
Solvay Public Event & Solvay Awards
The passion for science, the conviction that its
progress benefits to humanity are without doubt
values that Professor Françoise Barré-Sinoussi
has demonstrated during all her career.
The International Solvay Institutes are extremely
grateful to her for having accepted their invitation.
One of the main goals of the Solvay public lectures
is to awake scientific vocations among the
young people and particularly among young
women, who are underrepresented in scientific
disciplines. Let the brilliant career of the 2009
Solvay lecturer help change this unbalanced
situation!
25

Solvay Public Event & Solvay Awards
Solvay Awards
encouraged by their teachers that trusted in
their qualities and in their knowledge that
have been distinguished.
During those 20 years, technological developments
which were then unimaginable,
are now part of our daily life.
But it is also during the last two decades
that humanity realized that it has to face
new planetary challenges.
The energy consumption, the diminution of
fossil resources, greenhouse gas emissions,
the deep changes of our environment are
consequences of the industrial society but
also of the demographic growth with a
population that needs water, health and sufficient
food.
Speech by Jean-Marie Solvay
Member of the Board of Directors of Solvay S.A.
Already twenty years ago, at the behest
of Mr Jacques Solvay’s, my father, who is
doing us the honor of being here this afternoon,
the Solvay company created the
Solvay Awards, a prize to reward young
graduates from the Université Libre de Bruxelles
and a little bit later from the Vrij Universiteit
Brussel.
Since then, the work and projects of more
than 300 young men and women were
carefully examined by our judges. 162
among them were rewarded, 65 Doctors
of Sciences or Applied Sciences and 97
Masters, and Engineers. In this way, it is
an entire generation of young researchers
On the other hand new natural challenges
have also arisen to test our human society:
Aids, influenza, nosocomial diseases, water
quality of which are only examples.
The chemical industry in particular is ready
to accept today’s challenges but to meet
them, it has to lean on fundamental knowledge,
integrate it and invent technical solutions
and products that will provide a better
life and mitigate environmental changes.
If today, these advanced technological
solutions are ready to be industrialized it is
because intense research and collaboration
between academia and the industrial world
is a reality. This collaboration is rooted in
the sharing of powerful theoretical models,
the analysis of matter and deep knowledge
of its properties.
To succeed and to respond to the needs of
the people and the markets, the 21st century
industry will have to lean on knowledge
26

and competences of a new generation of
researchers familiar with most current developments
of sciences and technologies and
able to work with multidisciplinary teams
animated with an innovative spirit.
It is with this mind that the Solvay Awards
judges for the 2007 and 2008 years,
and for the first time with the help of the
academic corps of the ULB and VUB have
appointed the laureates.
The task was difficult because each candidate
was highly gifted. Those rewarded
this afternoon have shown themselves to be
capable of projecting their knowledge and
creating solutions for a responsible future
society.
They are with 14 laureates issued from both
universities of the Sciences and Applied Sciences
faculties.
We warmly congratulate them.
Solvay Awards
Solvay Public Event & Solvay Awards
2007 and 2008 Solvay Awards Laureates
Arnaud Boisdenghien (ULB)
Keevin Didriche (ULB)
Tim Fievez (VUB)
Jonathan Ghesquiere (ULB)
Leslie Herman (ULB)
Cedric Meuter (ULB)
Hans Miltner (VUB)
Evelyne Nguyen (ULB)
Julien Niset (ULB)
Bart Rimez (VUB)
Laurence Rongy (ULB)
Ine Schoukens (VUB)
Julien Smeets (ULB)
Benoît Tylleman (ULB)
27

Professor Richard J. SAYKALLY
International Solvay
Chairs
International Solvay Chairs
29

International Solvay Chairs
The Solvay Chairs in Physics started in 2006 and the Solvay
Chairs in Chemistry in 2008. These chairs enable the International
Solvay Institutes to invite in Brussels an eminent scientist
for a period of one to two months in order to give lectures on
her or his research work to researchers in the corresponding
field, not only from the ULB and the VUB, but also from other
Belgian universities and abroad. The course of lectures is preceded
by an inaugural lecture aimed at a broader audience.
The lectures are integrated in the curriculum of students at the
master or doctoral level.
Since its inception, there has been a total of six chairs, four in
physics and two in chemistry.
The 2009 International Solvay Chairs are described in separate
sections.
Past Chairs
Solvay Chairs in Physics
2009 - Professor Valery Rubakov (Institute for Nuclear Research
of the Russian Academy of Sciences, Moscow, Russia)
2008 - Professor David Gross (Kavli Institute for Theoretical
Physics, Santa Barbara, USA)
2007 - Professor Sir Michael Berry (University of Bristol,
United Kingdom)
2006 - Professor Ludwig Faddeev (Steklov Mathematical
Institute, Saint-Petersburg, Russia)
Solvay Chairs in Chemistry
2009 - Professor Alexander Mikhailov (Fritz Haber Institute of
the Max Planck Society, Berlin, Germany)
2008 - Professor Richard J. Saykally (University of Berkeley,
USA)
30

2009 International Solvay
Chair in Chemistry
Professor
Alexander MIKHAILOV
Fritz Haber Institute
of the Max Planck Society
Berlin, Germany
14 April – 13 June 2009
31

International Solvay Chair in Chemistry
The International Solvay Institutes were very
proud that Professor Alexander Mikhailov,
director of the department of physical chemistry
at the Fritz Haber Institute of the Max Planck
Society, accepted to be the 2009 year chair
holder in chemistry. Professor Mikhailov spent
two months in Brussels, from mid-April to mid-
June 2009. He was hosted by the groups of
Professors Anne De Wit and Pierre Gaspard at
ULB. His teaching was integrated in the curriculum
of the master degree in chemistry.
The International Solvay Chair in Chemistry has
been been possible thanks to a special grant
from the Solvay Company, which is gratefully
acknowledged.
Professor Alexander Mikhailov got his PhD degree from
the Lomonosov State University of Moscow in 1976.
After helding various positions in Germany and Russia,
he joined the Fritz Haber Institute in 1992, where he
became in 1995 senior staff scientist and then director of
the Complex Systems Group.
Professor Mikhailov made pioneering contributions
to various fields of physical chemistry, ranging from
pattern formation in nonlinear systems far from equilibrium
(which can be chemical or biological systems), to
nonequilibrium soft matter (Langmuir monolayers, biomembranes),
statistical physics of single biomolecules,
molecular machines and interactions between them, as
well as complex systems and chaos.
He has been invited as distinguished visiting professor or
lecturer in many institutions around the world. He received
also the prestigious Humboldt Research Award in
1993 for his work. He is in addition editor, editor-in-chief
or member of the advisory board of many of the leading
journals in the area.
Programme
Inaugural Lecture (21 April 2009)
“From Structure to Function: Chemistry in Transition”
Traditional physical chemistry has been
focused on explaining structural properties
of individual chemical objects and elementary
reaction events involving them. Today,
we realize that this knowledge is far from
sufficient to understand the known complex
chemical systems. Not only in the realm
of biology, but even for classical reactions
of heterogeneous catalysis, emergence of
coherent collective behavior – often yielding
the ultimate function of a chemical system –
is a process that needs to be understood. In
this lecture, I provide a personal overview
of the developments in studies of chemical
self-organization phenomena in the last
decades and discuss some trends of future
research.
32

Lectures
22 April 2009
Lecture 1
“Rich life on catalytic surfaces”
Reactions involving atoms adsorbed on
metal surfaces are broadly employed in
chemical technology and have a long
history of investigation. But only relatively
recently could one look with an electronic
microscope at what is actually taking
place on a catalytic surface during such a
reaction. It has been a surprise that most
of such reactions do not proceed under
steady kinetic conditions, as often has
been assumed. Instead, a rich repertoire
of complex wave processes and nonequlibrium
self-organized patterns has been
revealed.
29 April 2009
Lecture 2
“Why stainless steel breaks down?”
Stainless steel is naturally protected by oxide
layer that inhibits further oxidation. However,
pitting corrosion – a process which
is responsible for a third of all chemical
plant failures and is crucial for the safety of
nuclear reactors and nuclear waste disposal
– can still set on, breaking the material
down. The sudden onset of pitting corrosion
is explained by autocatalytic reproduction
of metastable corrosion pits and by spreading
of corrosion activation waves, possibly
yielding the most important practical example
of nonequilibrium chemical pattern
formation phenomena.
Professor Alexander MIKHAILOV
6 May 2009
Lecture 3
“Reactive soft matter: a new challenge”
Soft matter is characterized by presence of
weak energetic cohesion between its constituting
molecules. Because molecular interactions
are weak, such systems are highly
labile and typically possess a range of structural
equilibrium phase transitions. Chemical
reactions and diffusion of reactants interplay
with structural phase transitions, resulting in
the emergence of a variety of nonequilibrium
structures whose characteristic lengths
may well go into the nanoscale domain.
Such structures, which still remain relatively
poorly investigated, play a fundamental role
in the operation of any living cell.
13 May 2009
Lecture 4
“Understanding protein machines”
Mechanical machines, examples of which
can be already seen in beautiful drawings by
Leonardo da Vinci, have formed the basis of
the Industrial Revolution of the 18th century. If
we look at biological cells, we find strikingly
similar mechanical devices which however
operate at the nanoscale and in the presence
of strong thermal and environmental
fluctuations. How a protein molecule should
be organized in order to act as a robust
mechano-chemical device? How interactions
between such molecular machines can
produce complex, but yet coherent collective
behavior? Learning this is important not only
to better understand the nature of real living
cells, but also to proceed further with the design
of artificial protein machines and engineering
of their large functional ensembles.
33
International Solvay Chairs

2009 International Solvay
Chair in Physics
Professor Valery RUBAKOV
Institute for Nuclear Research
of the Russian Academy
of Sciences
Moscow, Russia
15 September – 31 October 2009
35

International Solvay Chair in Physics
The International Solvay Institutes were extremely
lucky and grateful that Professor Rubakov,
from the Institute for Nuclear Research of
the Russian Academy of Sciences in Moscow,
accepted to be the 2009 Solvay Professor in
Physics.
Professor Valery Rubakov was the host of the
research groups of Professors Jean-Marie Frère
(ULB), Marc Henneaux (ULB and International
Solvay Institutes) and Alexander Sevrin (VUB
and International Solvay Institutes). He spent
one and a half month in Brussels, from mid-September
through the end of October 2009.
His teaching was included in the training of the
International Doctoral School “Quantum Field
Theory, Strings and Gravity” (Amsterdam-Brussels-Paris).
Professor Valery Rubakov is one of the prominent Russian theoretical physicists. His interests
cover quantum field theory, high energy physics and cosmology. He got his doctoral degree in
1981 on the ”Vacuum structure in gauge quantum field theories”. Since 1981 until now, he has
been associated with the Institute for Nuclear Research (INR) in Moscow, where he
is currently leading researcher. In 1997 he became full member of the Russian
Academy of Sciences and since 1999 he is also professor (now honorary
professor) at Moscow State University.
He made key advances in quantum field theory by contributing fundamental
understanding of the structure and physical role of nonperturbative solutions:
solitons, monopoles, instantons, which are present in the theory because of
the nonlinearity of the field equations. He wrote a textbook on the subject
which has become a classic. In cosmology, he was the first to suggest
that we live on a brane – the so-called brane world scenario – in a paper
written as early as in 1983. He is currently working on dark matter
and dark energy (but not only), which are some of the most puzzling
challenges in the field.
Professor Rubakov got many honors and awards, among which the
Golden Medal and Prize of the Russian Academy of Sciences for
Young Scientists (1985), the A.A.Fridman Prize of the Russian Academy
of Sciences (1999) and the I.Ya.Pomeranchuk Prize of the Institute of
Theoretical and Experimental Physics (2003) for (and I quote the citation)
“pioneering contribution to developing and novel application of
nonperturbative methods in field theory”. He is regularly invited as
distinguished guest in the world leading scientific institutions.
He is the founder of a scientific school: many of his former students
work successfully in Russia and all over the world.
36

Programme
29 September 2009
Inaugural Lecture
“Particle physics and cosmology: towards
understanding the Universe”
Knowledge gained so far in cosmology is to
a large extent orthogonal to current
knowledge in particle physics. There is matter
and no anti-matter in our Universe,
and we do not have a unique explanation
of this asymmetry. There is dark matter in
the cosmos, and we do not know what the
particles are it consists of. Cosmological
expansion accelerates, and we do not
know the fundamental physics behind this
bizarre behavior. The origin of galaxies must
have roots deep in quantum field theory,
but we still have only a crude idea of what
they are. Amazingly, all these mysteries
will most probably be solved in a reasonably
near future. I review these and other
issues at the interface of particle physics
and cosmology, with an emphasis on future
progress in our understanding of the Universe.
Professor Valery RUBAKOV
Lectures
”Lectures on Inflation”
Abstract
The lectures will explain the inflationary
cosmological model and its virtues. In
particular, what inflation predicts for density
perturbations and gravity waves, and what
could be alternatives, will be discussed.
5 October 2009 : Lecture 1
6 October 2009 : Lecture 2
7 October 2009 : Lecture 3
8 October 2009 : Lecture 4
International Solvay Chairs
37

Symposium “The logic of gene regulatory networks”
Workshops
and Schools
organized by
the Institutes
Workshops and Schools organised by the Institutes
39

Workshop on “Sparsity,
learning and computation”
12 - 14 February 2009
Workshop on
"Sparsity,
learning and computa
Salle Solvay, Campus Plaine,
Université Libre de Bruxelles
B r u s s e l s , 1 2 - 1 4 F e b r u a r y
Scientifi c Committee
Ingrid Daubechies (Princeton University, USA)
Michel Defrise (VUB, Brussels, Belgium)
Christine De Mol (ULB, Brussels, Belgium)
Ignace Loris (VUB, Brussels, Belgium)
Organizing Committee
Ingrid Daubechies (Princeton University, USA)
Michel Defrise (VUB, Brussels, Belgium)
Christine De Mol (ULB, Brussels, Belgium)
Isabelle Juif (Solvay Institutes, Brussels, Belgium)
Ignace Loris (VUB, Brussels, Belgium)
Speakers
Richard Baraniuk (Rice Unive
Mario Bertero (Università
Emmanuel Candès (Califor
Pasa
Albert Cohen (Universi
Ingrid Daubechies (Pr
Ron DeVore (Univers
Anna Gilbert (Unive
Rémi Gribonval (U
Gérard Kerkyacha
John Lafferty (C
Robert Nowak
Dominique Pic
Tomaso Pogg
Stephen S
Alessand
Martin
Web site of t he Symposium :
ht p : / / www. solvayinstitutes . be / Activities / Spar
Avec le soutien de la Ministre de l’Enseignement supérieur et d
Dit project wordt ondersteund binnen het Actieplan Wetenschapscommu
41

Workshops and Schools
organized by the Institutes
The recent emergence, in different areas in the mathematical sciences, of the concept of “sparsity”
has led to new insights that promise to have profound implications in a wide range of fields. To realize
this promise, important mathematical challenges will have to be met first. The workshop has concentrated
on these challenges, their precise formulation and the progress we are making towards
solving them. It has also highlighted applications in the sciences and in engineering, including (but
not restricted to) imaging and communications.
This workshop has brought together experts from the exact and applied sciences, including pure
and applied mathematicians, statisticians and computer scientists, as well as physicists and engineers
in various subdisciplines.
Scientific Committee
Ingrid Daubechies
(Princeton University, USA)
Michel Defrise
(VUB, Brussels, Belgium)
Christine De Mol
(ULB, Brussels, Belgium)
Ignace Loris
(VUB, Brussels, Belgium)
Organising Committee
Ingrid Daubechies
(Princeton University, USA)
Michel Defrise
(VUB, Brussels, Belgium)
Christine De Mol
(ULB, Brussels, Belgium)
Isabelle Juif
(Solvay Institutes, Brussels, Belgium)
Ignace Loris
(VUB, Brussels, Belgium)
List of Invited Speakers
Richard Baraniuk
(Rice University, Houston, USA)
Mario Bertero
(Università degli Studi di Genova, Italy)
Albert Cohen
(Université Pierre et Marie Curie, Paris, France)
Ingrid Daubechies
(Princeton University, USA)
Ron DeVore
(University of South Carolina, Columbia, USA)
Anna Gilbert
(University of Michigan, Ann Arbor, USA)
Rémi Gribonval
(Université Rennes 1, France)
Gérard Kerkyacharian
(Université Paris VI, France)
John Lafferty
(Carnegie Mellon University, Pittsburgh, USA)
Robert Nowak
(University of Wisconsin-Madison, USA)
Dominique Picard
(Université Paris VII, France)
Amit Singer
(Princeton University, USA)
Stephen Smale
(University of California, Berkeley, USA)
Alessandro Verri
(Università degli Studi di Genova, Italy)
Martin Vetterli
(Ecole Polytechnique Fédérale de Lausanne,
Switzerland)
42

Workshop on “Sparsity, learning and computation”
Workshop on
"Sparsity,
learning and computation"
Salle Solvay, Campus Plaine,
Université Libre de Bruxelles
B r u s s e l s , 1 2 - 1 4 F e b r u a r y 2 0 0 9
Scientifi c Committee
Ingrid Daubechies (Princeton University, USA)
Michel Defrise (VUB, Brussels, Belgium)
Christine De Mol (ULB, Brussels, Belgium)
Ignace Loris (VUB, Brussels, Belgium)
Organizing Committee
Ingrid Daubechies (Princeton University, USA)
Michel Defrise (VUB, Brussels, Belgium)
Christine De Mol (ULB, Brussels, Belgium)
Isabelle Juif (Solvay Institutes, Brussels, Belgium)
Ignace Loris (VUB, Brussels, Belgium)
Speakers
Richard Baraniuk (Rice University, Houston, USA)
Mario Bertero (Università degli Studi di Genova, Italy)
Emmanuel Candès (California Institute of Technology,
Pasadena, USA)
Albert Cohen (Université Paris VI, France)
Ingrid Daubechies (Princeton University, USA)
Ron DeVore (University of South Carolina, Columbia, USA)
Anna Gilbert (University of Michigan, Ann Arbor, USA)
Rémi Gribonval (Université Rennes 1, France)
Gérard Kerkyacharian (Université Paris VI, France)
John Lafferty (Carnegie Mellon University, Pittsburgh, USA)
Robert Nowak (University of Wisconsin-Madison, USA)
Dominique Picard (Université Paris VII, France)
Tomaso Poggio (Massachusetts Institute of Technology,
Cambridge, USA)
Stephen Smale (University of California, Berkeley, USA)
Alessandro Verri (Università degli Studi di Genova, Italy)
Martin Vetterli (Ecole Polytechnique Fédérale de Lausanne,
Switzerland)
Workshops and Schools organised by the Institutes
W e b s i t e o f t h e S y m p o s i u m :
h t t p : / / w w w. s o l v a y i n s t i t u t e s . b e / A c t i v i t i e s / S p a r s i t y / S p a r s i t y. h t m l
Avec le soutien de la Ministre de l’Enseignement supérieur et de la Recherche scientifique.
Dit project wordt ondersteund binnen het Actieplan Wetenschapscommunicatie, een initiatief van de Vlaamse Regering.
Graphic Design: info@imagedemarc.be
43

Workshops and Schools
organized by the Institutes
Scientific Programme
Thursday 12 February 2009
08:30 - 09:15 Registration
09:15 - 09:25 Welcome Address by M. Henneaux, Director
of the Solvay Institutes
09:25 - 10:15 M. Bertero (Università degli Studi di Genova)
Gradient projection methods for constrained image denoising and
deblurring
10:15 - 10:45 Coffee Break
10:45 - 11:35 A. Verri (Università degli Studi di Genova)
Learning Sparse Representations in Computational Biology
11:35 - 12:25 R. Gribonval (Université Rennes 1)
How many training samples does it take to learn a dictionary for
sparse representations?
12:25 - 14:10 Lunch
14:10 - 15:00 S. Smale (University of California)
Geometry of Data
15:00 - 15:50 R. DeVore (University of South Carolina)
Capturing a function of few variables in high
dimensions
Friday 13 February 2009
09:00 - 09:50 M. Vetterli (Ecole Polytechnique Fédérale de
Lausanne)
Sparse Sampling: Variations on a Theme by
Shannon
09:50 - 10:40 D. Picard (Université Paris VII)
Deconvolution methods for estimating sparse
density on the sphere
10:40 - 11:10 Coffee Break
44

Workshop on “Sparsity, learning and computation”
11:10 - 12:00 J. Lafferty (Carnegie Mellon University)
Functional Sparsity: Nonparametric Methods
for High Dimensional Data
12:00 - 14:00 Lunch
14:00 - 14:50 A. Gilbert (University of Michigan)
Sparse matrices, sparse signals, and sparse
algorithms
14:50 - 15:20 Coffee Break
15:20 - 16:10 R. Nowak (University of Wisconsin-Madison)
Can’t learn without you
16:10 - 17:00 R. Baraniuk (Rice University)
Model-based compressive sensing
Saturday 14 February 2009
Workshops and Schools organised by the Institutes
09:00 - 09:50 A. Cohen (Université Pierre et Marie Curie)
Sparse polynomial representations in high dimension and
applications to stochastic PDE’s
09:50 - 10:40 G. Kerkyacharian (Université Paris VI)
Sparsity and Radon Transform: Needlet estimation
10:40 - 11:10 Coffee Break
11:10 - 12:00 A. Singer (Princeton University)
Structure Determination through Eigenvectors of Sparse Operators
12:00 - 12:50 I. Daubechies (Princeton University)
Sparsity without l1-minimization
45

Workshops and Schools
organized by the Institutes
List of Participants
First Name Last Name Institution
Jan Aelterman Universiteit Gent, Belgium
Musa Alrefaya Vrije Universiteit Brussel, Belgium
Borislav Antic University of Novi Sad, Serbia
Jean-Pierre Antoine Université Catholique de Louvain,Belgium
Chris Antonopoulos Université Libre de Bruxelles, Belgium
Lennert Appeltant Vrije Universiteit Brussel, Belgium
Danilo Babin Universiteit Gent, Belgium
Joeri Barbarien Vrije Universiteit Brussel, Belgium
Vasileios Basios Université Libre de Bruxelles, Belgium
Lamiae Bentabet Université Libre de Bruxelles, Belgium
Alexander Borghgraef Royal Military Academy, Brussels, Belgium
Vincent Botta Université de Liège, Belgium
Philippe Boulanger Universite Libre de Bruxelles, Belgium
Philippe Cara Vrije Universiteit Brussel, Belgium
Carlo Cattani Università degli studi di Salerno, Italy
Chia-Tche Chang Université Catholique de Louvain, Belgium
Catherine Charles Faculté Universitaire des Sciences
Agronomiques de Gembloux, Belgium
Peter Clerinx K.U.Leuven, Belgium
Christophe Cloquet Université Libre de Bruxelles, Belgium
Bruno Cornelis Vrije Universiteit Brussel, Belgium
Jan Cornelis Vrije Universiteit Brussel, Belgium
Balazs Csaji Université Catholique de Louvain, Belgium
Christine De Mol Université Libre de Bruxelles, Belgium
Christophe De Vleeschouwer Université Catholique de Louvain, Belgium
Alex Deckmyn Royal Meteorological Institute, Brussels, Belgium
Michel Defrise Vrije Universiteit Brussel, Belgium
Nikos Deligiannis Vrije Universiteit Brussel, Belgium
Veronique Delouille Royal Observatory of Belgium, Brussels, Belgium
Thomas Dhollander K.U.Leuven, Belgium
Luca Dimiccoli Vrije Universiteit Brussel, Belgium
Ann Dooms Vrije Universiteit Brussel, Belgium
Pierre Dupont Université Catholique de Louvain, Belgium
Tillmann Falck K.U.Leuven, Belgium
Massimo Fornasier Johann Radon Institute for Computational
and Applied Mathematics, Linz, Austria
46

Workshop on “Sparsity, learning and computation”
Workshops and Schools organised by the Institutes
47

Workshops and Schools
organized by the Institutes
List of Participants
First Name Last Name Institution
Amir Forouzan K.U.Leuven, Belgium
Kevin Françoisse Université Catholique de Louvain, Belgium
Jean-Marc Freyermuth Université Catholique de Louvain, Belgium
Pierre Geurts Université de Liège, Belgium
Nicolas Gillis Université Catholique de Louvain, Belgium
Bart Goossens Universiteit Gent, Belgium
Jean-Pierre Gossez Université Libre de Bruxelles, Belgium
Marc Hallin Université Libre de Bruxelles, Belgium
Thibault Helleputte Université Catholique de Louvain, Belgium
Ruben Hillewaere Vrije Universiteit Brussel, Belgium
Ronny Hoffmann Vrije Universiteit Brussel, Belgium
Van Anh Huynh-Thu Université de Liège, Belgium
Ernesto Iacucci K.U.Leuven, Belgium
Vedran Jelaca Universiteit Gent, Belgium
Loïc Lecharlier Faculté Universitaire des Sciences
Agronomiques de Gembloux, Belgium
Ignace Loris Vrije Universiteit Brussel, Belgium
Hiep Luong Universiteit Gent, Belgium
Benoit Macq Université Catholique de Louvain, Belgium
Jean-Marie Mirebeau Université Paris 6, France
Adrian Munteanu Vrije Universiteit Brussel, Belgium
Juan Pablo Narino Mendoza Universite Catholique de Louvain, Belgium
Fabian Ojeda K.U.Leuven, Belgium
Davy Paindaveine Université Libre de Bruxelles, Belgium
Aleksandra Pizurica Universiteit Gent, Belgium
Holger Rauhut Universität Bonn, Germany
Simone Righi Facultés Universitaires Notre-Dame de la Paix,
Namur, Belgium
Elizabete Rodrigues Ferreira Université Libre de Bruxelles, Belgium
Filip Rooms Universiteit Gent, Belgium
Tijana Ruzic Universiteit Gent, Belgium
Hichem Sahli Vrije Universiteit Brussel, Belgium
Chafik Samir Université Catholique de Louvain, Belgium
Shahid Satti Vrije Universiteit Brussel, Belgium
48

Workshop on “Sparsity, learning and computation”
List of Participants
First Name Last Name Institution
Peter Schelkens Vrije Universiteit Brussel, Belgium
Marco Signoretto K.U.Leuven, Belgium
Seyfollah Soleimani Universiteit Gent, Belgium
Florent Sureau Vrije Universiteit Brussel, Belgium
Nizar Touleimat Université Catholique de Louvain, Belgium
Caroline Verhoeven Vrije Universiteit Brussel, Belgium
Rainer von Sachs Université Catholique de Louvain, Belgium
Rachel Ward Princeton University, USA
Roman Zakharov Université Catholique de Louvain, Belgium
Peyman Zarrineh K.U.Leuven, Belgium
Workshops and Schools organised by the Institutes
49

Workshop on
“Cosmological Frontiers
in Fundamental Physics”
13 - 16 May 2009
Workshop on
Cosmological Frontiers
in Fundamental Physics
organized by
International Solvay Institutes (Brussels, Belgium)
Laboratoire APC (Paris, France)
Perimeter Institute (Waterloo, Canada)
Scientific Committee
Pierre Binétruy (APC)
Ben Craps (VUB)
Marc Henneaux (Solvay Inst.)
Thomas Hertog (APC)
Gary Horowitz (UCSB)
Shamit Kachru (Stanford)
Justin Khoury (Penn)
Juan Maldacena (IAS)
Valery Rubakov (RAS)
Neil Turok (PI)
Brussels, 13-16 May 2009
www.solvayinstitutes.be/Activities/CosmoFrontiers/CFFP.html
Photo credit: NASA/ESA/
S. Beckwith (STScI)
and The HUDF Team
Invited Speakers
Pierre Binétruy (APC)
Matthias Blau (Bern)
Thibault Damour (IHES)
Gia Dvali (CERN)
Gary Horowitz (UCSB)
Shamit Kachru (Stanford)
Renata Kallosh (Stanford)
Justin Khoury (Penn)
Lev Kofman (Toronto)
Eiichiro Komatsu (UT Austin)
Andrei Linde (Stanford)
Liam McAllister (Cornell)
Viatcheslav Mukhanov (LMU)
Hermann Nicolai (Golm)
Savdeep Sethi (Chicago)
Stephen Shenker (Stanford)
Eva Silverstein (Stanford)
Paul Steinhardt (Princeton)
Leonard Susskind (Stanford)
Sandip Trivedi (Tata Inst.)
Neil Turok (PI)
Gabriele Veneziano (CdF)
Erik Verlinde (Amsterdam)
Benjamin Wandelt (UIUC)
Organizing Committee
Ben Craps (VUB)
Thomas Hertog (APC)
Peter Tinyakov (ULB)
Michel Tytgat (ULB)
Avec le soutien de la Minis
supérieur et de la
Dit project wordt ondersteund binnen het Actieplan Wetenschapscommunicatie, een initiatief v
51

Workshops and Schools
organized by the Institutes
Jointly with the Perimeter Institute (Waterloo,
Canada) and the APC Institute (Paris), the International
Solvay Institutes organized a workshop
on “Cosmological Frontiers in Fundamental
Physics”, held in Brussels from Wednesday May
13 until Saturday May 16, 2009. Its aim was to
discuss, in an informal setting, recent developments
at the interface of cosmology and fundamental
physics, in particular string theory.
The workshop was part of a series initiated by
PI and APC. The workshops will from now on
rotate between the three places, the next edition
taking place at PI in June 2010. It was also part
of a series of focused workshops organized by
the International Solvay Institutes.
Workshop on
Cosmological Frontiers
in Fundamental Physics
organized by
International Solvay Institutes (Brussels, Belgium)
Laboratoire APC (Paris, France)
Perimeter Institute (Waterloo, Canada)
Brussels, 13-16 May 2009
www.solvayinstitutes.be/Activities/CosmoFrontiers/CFFP.html
Scientific Committee
Pierre Binétruy
(Université Paris VII, France)
Ben Craps
(Vrije Universiteit Brussel, Belgium)
Marc Henneaux
(Solvay Institutes, Brussels, Belgium)
Thomas Hertog
(Université Paris VII, France)
Gary Horowitz
(University of California, Santa Barbara, USA)
Shamit Kachru
(Stanford University, USA)
Justin Khoury
(University of Pennsylvania, Philadelphia, USA)
Juan Maldacena
(Institute for Advanced Study, Princeton, USA)
Valery Rubakov
(Russian Academy of Sciences, Moscow, Russia)
Neil Turok
(Perimeter Institute for Theoretical Physics, Waterloo,
Canada)
Organising Committee
Scientific Committee
Pierre Binétruy (APC)
Ben Craps (VUB)
Marc Henneaux (Solvay Inst.)
Thomas Hertog (APC)
Gary Horowitz (UCSB)
Shamit Kachru (Stanford)
Justin Khoury (Penn)
Juan Maldacena (IAS)
Valery Rubakov (RAS)
Neil Turok (PI)
Invited Speakers
Pierre Binétruy (APC)
Matthias Blau (Bern)
Thibault Damour (IHES)
Gia Dvali (CERN)
Gary Horowitz (UCSB)
Shamit Kachru (Stanford)
Renata Kallosh (Stanford)
Justin Khoury (Penn)
Lev Kofman (Toronto)
Eiichiro Komatsu (UT Austin)
Andrei Linde (Stanford)
Liam McAllister (Cornell)
Viatcheslav Mukhanov (LMU)
Hermann Nicolai (Golm)
Savdeep Sethi (Chicago)
Stephen Shenker (Stanford)
Eva Silverstein (Stanford)
Paul Steinhardt (Princeton)
Leonard Susskind (Stanford)
Sandip Trivedi (Tata Inst.)
Neil Turok (PI)
Gabriele Veneziano (CdF)
Erik Verlinde (Amsterdam)
Benjamin Wandelt (UIUC)
Organizing Committee
Ben Craps (VUB)
Thomas Hertog (APC)
Peter Tinyakov (ULB)
Michel Tytgat (ULB)
Ben Craps
(Vrije Universiteit Brussel, Belgium)
Thomas Hertog
(Université Paris VII, France)
Peter Tinyakov
(Université Libre de Bruxelles, Belgium)
Michel Tytgat
(Université Libre de Bruxelles, Belgium)
Photo credit: NASA/ESA/
S. Beckwith (STScI)
and The HUDF Team
Avec le soutien de la Ministre de l’Enseignement
supérieur et de la Recherche scientifique.
Dit project wordt ondersteund binnen het Actieplan Wetenschapscommunicatie, een initiatief van de Vlaamse Regering.
52

List of Invited Speakers
Pierre Binétruy
(Université Paris VII, France)
Matthias Blau
(Universität Bern, Switzerland)
Thibault Damour
(IHES, Bures-sur-Yvette, France)
Jan de Boer
(Universiteit van Amsterdam, the Netherlands)
Gia Dvali
(CERN, Genève, Switzerland)
Gary Horowitz
(University of California, Santa Barbara, USA)
Renata Kallosh
(Stanford University, USA)
Justin Khoury
(University of Pennsylvania, Philadelphia, USA)
Elias Kiritsis
(University of Crete, Heraklion, Greece)
Eiichiro Komatsu
(University of Texas, Austin, USA)
Andrei Linde
(Stanford University, USA)
Workshop on “Cosmological Frontiers in
Fundamental Physics”
Liam McAllister
(Cornell University, Ithaca, USA)
Viatcheslav Mukhanov
(Ludwig-Maximilians-Universität München,
Germany)
Hermann Nicolai
(Max-Planck-Institut für Gravitationsphysik,
Golm, Germany)
Fernando Quevedo
(Cambridge University, UK)
Simon Ross
(Durham University, UK)
Savdeep Sethi
(University of Chicago, USA)
Paul Steinhardt
(Princeton University, USA)
Sandip Trivedi
(Tata Institute of Fundamental Research,
Mumbai, India)
Neil Turok
(Perimeter Institute for Theoretical Physics, Waterloo,
Canada)
Erik Verlinde
(Universiteit van Amsterdam, the Netherlands)
Workshops and Schools organised by the Institutes
53

Workshops and Schools
organized by the Institutes
Scientific Programme
Wednesday 13 May 2009
09:30 - 10:30 Registration
Chair
B. Craps
10:30 - 10:35 Welcome Address by M. Henneaux, Director of the Solvay Institutes
10:35 - 11:20 E. Komatsu (University of Texas)
Non-Gaussianity as a Probe of the Physics of the Primordial Universe
11:20 - 12:05 J. Khoury (University of Pennsylvania)
Rapidly-Varying Sound Speed, Scale-Invariance and
Non-Gaussian Signatures
12:05 - 14:00 Lunch
Chair
M. Tytgat
14:00 - 14:45 P. Binetruy (Université Paris VII)
Dark energy and fundamental physics
14:45 - 15:30 G. Dvali (CERN)
Black holes and origin of species
15:30 - 16:15 Coffee Break
Chair
P. Tinyakov
16:15 - 17:00 T. Damour (IHES)
Supergravity, Cosmo-Billiards and Kac-Moody Algebras
17:00 - 17:45 J. de Boer (Universiteit van Amsterdam)
Macroscopic quantum effects near black holes
Thursday 14 May 2009
Chair
A. Sevrin
09:30 - 10:15 G. Horowitz (University of California)
A New Holographic View of Singularities
54

Scientific Programme
Workshop on “Cosmological Frontiers in
Fundamental Physics”
10:15 - 11:00 M. Blau (Universität Bern)
Penrose limits of Space-Time Singularities and Matrix Big Bang Models
11:00 - 11:30 Coffee Break
11:30 - 12:15 N. Turok (Perimeter Institute for Theoretical Physics)
Holographic Resolution of Cosmological Singularities
12:15 - 14:00 Lunch
Chair
J. Troost
14:00 - 14:45 S. Trivedi (Tata Institute of Fundamental Research)
Cosmological Singularities and their Field Theory Duals
14:45 - 15:30 E. Verlinde (Universiteit van Amsterdam)
Degenerate Matter and Gravitational Collapse in AdS/CFT
Workshops and Schools organised by the Institutes
15:30 - 16:00 Coffee Break
16:00 - 16:45 P. Steinhardt (Princeton University)
Cosmic Acceleration and Ekpyrosis in Theories with Extra Dimensions
Friday 15 May 2009
Chair
T. Hertog
09:30 - 10:15 A. Linde (Stanford University)
Inflationary Multiverse
10:15 - 11:00 L. McAllister (Cornell University)
Systematics of D-brane inflation
11:00 - 11:30 Coffee Break
11:30 - 12:15 H. Nicolai (Max-Planck-Institut für Gravitationsphysik)
Cosmological singularities, higher order curvature corrections, and E10
12:15 - 14:00 Lunch
55

Workshops and Schools
organized by the Institutes
Chair
A. Achucarro
14:00 - 14:45 R. Kallosh (Stanford University)
Recent developments in N=8 Supergravity
14:45 - 15:30 S. Sethi (University of Chicago)
Approaches to Time-dependent String Theory
15:30 - 16:00 Coffee Break
16:00 - 16:45 F. Quevedo (Cambridge University)
LARGE volume and cosmology
Saturday 16 May 2009
Chair
M. Henneaux
09:30 - 10:15 V. Mukhanov (Ludwig-Maximilians-Universität
München)
Vector dark energy
10:15 - 11:00 E. Kiritsis (University of Crete)
The cosmology of Horava-Lifshitz gravity
11:00 - 11:30 Coffee Break
11:30 - 12:15 S. Ross (Durham University)
Holography for non-relativistic CFTs
56

List of Participants
Workshop on “Cosmological Frontiers in
Fundamental Physics”
Last Name First Name Institution
Abou Zeid Mohab University of London, UK
Achucarro Ana Universiteit Leiden, the Netherlands
Argurio Riccardo Université Libre de Bruxelles, Belgium
Babichev Eugeny Université Paris VII, France
Bañados Max Pontificia Universidad Católica de Chile,Santiago, Chile
Barnich Glenn Université Libre de Bruxelles, Belgium
Battarra Lorenzo Université Paris VII, France
Bernamonti Alice Vrije Universiteit Brussel, Belgium
Bigazzi Francesco Université Libre de Bruxelles, Belgium
Bohé Alejandro Université Paris VII, France
Bouatta Nazim University of Cambridge, UK
Bucher Martin Université Paris XI, France
Clesse Sebastien Université Libre de Bruxelles, Belgium
Closset Cyril Université Libre de Bruxelles, Belgium
Cluzel Emeline CEA Saclay, Institut de Physique Théorique, France
Cotrone Aldo K.U.Leuven, Belgium
Craps Ben Vrije Universiteit Brussel, Belgium
D’Hondt Jorgen Vrije Universiteit Brussel, Belgium
De Roo Frederik Vrije Universiteit Brussel, Belgium
Dehouck Francois Université Libre de Bruxelles, Belgium
Deruelle Nathalie Université Paris VII, France
Dymarsky Anatoly Stanford University, USA
Englert Francois Université Libre de Bruxelles, Belgium
Evnin Oleg Vrije Universiteit Brussel, Belgium
Ferrari Frank Université Libre de Bruxelles, Belgium
Galli Federico Vrije Universiteit Brussel, Belgium
Henneaux Marc Université Libre de Bruxelles & Solvay
Institutes, Brussels, Belgium
Hertog Thomas Université Paris VII, France
Honecker Gabriele K.U.Leuven, Belgium
Houart Laurent Université Libre de Bruxelles, Belgium
Jackson Mark Universiteit Leiden, the Netherlands
Jamsin Ella Université Libre de Bruxelles, Belgium
Joukovskaya Liudmila University of Cambridge, UK
Kim Sung-Soo Université Libre de Bruxelles, Belgium
57
Workshops and Schools organised by the Institutes

Workshops and Schools
organized by the Institutes
List of Participants
Last Name First Name Institution
Kleinschmidt Axel Université Libre de Bruxelles, Belgium
Konduru Rakesh Teja Sri Venkateswara University, Tirupati, India
Koshelev Alexey Vrije Universiteit Brussel, Belgium
Krishnan Chethan International Solvay Institutes, Brussels, Belgium
Kuperstein Stanislav Vrije Universiteit Brussel, Belgium
Lehners Jean-Luc Princeton University, USA
Lindman Hornlund Josef Université Libre de Bruxelles, Belgium
Maccaferri Carlo Université Libre de Bruxelles, Belgium
Maharana Jnanadeva Institute of Physics, Bhubaneswar, Orissa, India
McFadden Paul Universiteit van Amsterdam, the Netherlands
Meerburg Daniel Universiteit van Amsterdam, the Netherlands
Montañez Sergio Université Libre de Bruxelles, Belgium
Nitti Francesco Université Paris VII, France
Parikh Maulik The Inter-University Centre for Astronomy & Astrophysics,
Pune, India
Perz Jan K.U.Leuven, Belgium
Renaux-Petel Sebastien Université Paris VII, France
Ribassin Julien Université Paris VII, France
Ribeiro Raquel University of Cambridge, UK
Ringeval Christiophe Université Catholique de Louvain, Belgium
Schalm Koenraad Universiteit Leiden, the Netherlands
Schoots Leo Independent researcher
Sevrin Alexander Vrije Universiteit Brussel, Belgium
Skordis Constantinos Perimeter Institute, Waterloo, Canada
Spindel Philippe Université de Mons, Belgium
Staessens Wieland Vrije Universiteit Brussel, Belgium
Steer Daniele Université Paris VII, France
Stein Maren University of Cambridge, UK
Tinyakov Peter Université Libre de Bruxelles, Belgium
Troost Jan Ecole Normale Supérieure, Paris, France
Tytgat Michel Université Libre de Bruxelles, Belgium
van der Schaar Jan Pieter Universiteit van Amsterdam, the Netherlands
Van Proeyen Antoine K.U.Leuven, Belgium
Vikman Alexander New York University, USA
Virmani Amitabh Université Libre de Bruxelles, Belgium
58

List of Participants
Workshop on “Cosmological Frontiers in
Fundamental Physics”
Last Name First Name Institution
Wesley Daniel University of Cambridge, UK
Youssef Ahmed Université Paris VII, France
Zenaïdi Naïm Université Libre de Bruxelles, Belgium
Ziour Riad Université Paris VII, France
Workshops and Schools organised by the Institutes
59

Workshop on
“Chemo-hydrodynamic
patterns and instabilities”
28 - 30 October 2009
Organizing Committee
Solvay Workshop
Chemo-Hydrodynamic
Patter ns and Instabiliti
P. Colinet (Université Libre de Bruxelles)
P.C. Dauby (Université de Liège)
Y. De Decker (Université Libre de Bruxelles)
A. De Wit (Université Libre de Bruxelles)
I. Juif (Solvay Institutes & Université Libre de Bruxelles)
Dit project wordt ondersteund
binnen het Actieplan Wetenschapscommunicatie,
een initiatief
van de Vlaamse Regering.
Université Libre de Bruxelles
Brussels, 28 - 30 October 2009
Campus Plaine - Salle Solvay
Confirmed Invited Speakers
M.A. Bees (University of Glasgow, UK)
G. Desmet (Vrije Universiteit Brussel, Belgium)
A. D’Onofrio (Universidad de Buenos Aires, Argentina)
K. Eckert (Technische Universität Dresden, Germany)
J.M. Garcia Ruiz (Universidad de Granada, Spain)
M. Hauser (Otto-von-Guericke-Universität Magdeburg, Germany)
S. Morris (University of Toronto, Canada)
Z. Neufeld (University College Dublin, Ireland)
D. Quéré (Ecole Polytechnique, Palaiseau, France)
M. Quintard (Institut de Mécanique des Fluides, Toulouse, France
T. Solomon (Bucknell University, Lewisburg, USA)
P. Tabeling (École Supérieure de Physique et de Chimie Industrie
N. Vladimirova (University of Chicago, USA)
Scientific Committee
A. De Wit (Université Libre de Bruxelles, Bel
K. Eckert (Technische Universität Dresden
G.M. Homsy (University of California, Sa
S. Kalliadasis (Imperial College, London
V. Pimienta (Université Paul Sabatier, T
A. Pocheau (IRPHE, Marseille, France)
U. Thiele (Loughborough University,
A. Zebib (Rutgers University, Piscataw
Contributed papers and posters are invited. Pl
for more details of the conference and instruct
www.solvayinstitutes.be/Activities/Che
ITN
Multiflow
Avec le soutien de la Minis
de l’Enseignement supér
et de la Recherche sci
fique.
61

Workshops and Schools
organized by the Institutes
Organizing Committee
The workshop focused on discussing spatio-temporal
patterns and instabilities that appear when
chemical species are advected by complex
flows or when chemical reactions are able to
modify or trigger hydrodynamic flows by changing
a physical property (density, viscosity or
surface tension) of the fluid at hand. The various
topics addressed were typically convective
flows around chemical fronts, Marangoni flows
in reactive drops or films, chemical reactions in
porous media or complex flows, microfluidic and
biological applications of chemo-hydrodynamic
coupling.
Solvay Workshop
Chemo-Hydrodynamic
Patter ns and Instabilities
P. Colinet (Université Libre de Bruxelles)
P.C. Dauby (Université de Liège)
Y. De Decker (Université Libre de Bruxelles)
A. De Wit (Université Libre de Bruxelles)
I. Juif (Solvay Institutes & Université Libre de Bruxelles)
Université Libre de Bruxelles
Brussels, 28 - 30 October 2009
Campus Plaine - Salle Solvay
Confirmed Invited Speakers
M.A. Bees (University of Glasgow, UK)
G. Desmet (Vrije Universiteit Brussel, Belgium)
A. D’Onofrio (Universidad de Buenos Aires, Argentina)
K. Eckert (Technische Universität Dresden, Germany)
J.M. Garcia Ruiz (Universidad de Granada, Spain)
M. Hauser (Otto-von-Guericke-Universität Magdeburg, Germany)
S. Morris (University of Toronto, Canada)
Z. Neufeld (University College Dublin, Ireland)
D. Quéré (Ecole Polytechnique, Palaiseau, France)
M. Quintard (Institut de Mécanique des Fluides, Toulouse, France)
T. Solomon (Bucknell University, Lewisburg, USA)
P. Tabeling (École Supérieure de Physique et de Chimie Industrielles, Paris, France)
N. Vladimirova (University of Chicago, USA)
Scientific Committee
A. De Wit (Université Libre de Bruxelles, Belgium)
K. Eckert (Technische Universität Dresden, Germany)
G.M. Homsy (University of California, Santa Barbara, USA)
S. Kalliadasis (Imperial College, London, UK)
V. Pimienta (Université Paul Sabatier, Toulouse, France)
A. Pocheau (IRPHE, Marseille, France)
U. Thiele (Loughborough University, UK)
A. Zebib (Rutgers University, Piscataway, USA)
Contributed papers and posters are invited. Please see the workshop website
for more details of the conference and instructions for submitting applications.
www.solvayinstitutes.be/Activities/ChemoHydro/ChemoHydro.html
Scientific Committee
A. De Wit
(Université Libre de Bruxelles, Belgium)
K. Eckert
(Technische Universität Dresden, Germany)
G.M. Homsy
(University of California, Santa Barbara, USA)
S. Kalliadasis
(Imperial College, London, UK)
V. Pimienta
(Université Paul Sabatier, Toulouse, France)
A. Pocheau
(IRPHE, Marseille, France)
U. Thiele
(Loughborough University, UK)
A. Zebib
(Rutgers University, Piscataway, USA)
Organising Committee
P. Colinet
(Université Libre de Bruxelles, Belgium)
P. Dauby
(Université de Liège, Belgium)
Y. De Decker
(Université Libre de Bruxelles, Belgium)
A. De Wit
(Université Libre de Bruxelles, Belgium)
I. Juif
(Solvay Institutes & Université Libre de Bruxelles,
Belgium)
ITN
Multiflow
Dit project wordt ondersteund
Avec le soutien de la Ministre
binnen het Actieplan Wetenschapscommunicatie,
een initiatief
et de la Recherche scienti-
de l’Enseignement supérieur
van de Vlaamse Regering.
fique.
62

Workshop on
“Chemo-hydrodynamic patterns and instabilities”
List of Invited Speakers
M.A. Bees
(University of Glasgow, UK)
G. Desmet
(Vrije Universiteit Brussel, Belgium)
A. D’Onofrio
(Universidad de Buenos Aires, Argentina)
K. Eckert
(Technische Universität Dresden, Germany)
J.M. Garcia Ruiz
(Universidad de Granada, Spain)
M. Hauser
(Otto-von-Guericke-Universität Magdeburg,
Germany)
S. Morris
(University of Toronto, Canada)
Z. Neufeld
(University College Dublin, Ireland)
D. Quéré
(Ecole Polytechnique, Palaiseau, France)
M. Quintard
(Institut de Mécanique des Fluides, Toulouse,
France)
T. Solomon
(Bucknell University, Lewisburg, USA)
P. Tabeling
(École Supérieure de Physique et de Chimie
Industrielles, Paris, France)
N. Vladimirova
(University of Chicago, USA)
Workshops and Schools organised by the Institutes
63

Workshops and Schools
organized by the Institutes
List of posters
M. Al-Ghoul: Precipitation Pulse Propagation in the Ni(OH)2/NH3 System
C. Almarcha: Experimental study of hydrodynamic instabilities of A+B →> C reaction fronts in vertically
oriented Hele-Shaw cell.
V. Basios, Th. Dumont: Pattern formation in presence of phase transition: some computational challenges
G. Boffetta: Statistics of Rayleigh-Taylor turbulence
H. Rose and M. Britton: Magnetic Resonance Imaging of Viscous Fingering
G. Dumazer: Forbidden interval of propagation speed for exothermic chemical
fronts: from perfect gas to van der
L. Frastia, A.J. Archer, and U. Thiele: Thin film model for the formation of ring-like
deposits during the dewetting of suspensions
T. Gérard: Influence of heat losses through the walls of the reactor on Rayleigh-
Taylor fingering of exothermic autocatalytic fronts
F. Glaab: Hydroxide ion diffusion processes in modified silica garden systems
C. Herman: Inter-dependence between the microstructures in highly concentrated suspensions and
the micro-scale
N. Jarrige: Autocatalytic reaction flow in heterogeneous media using lattice BGK simulations
R. Maes: Experimental study of chemically-driven viscous fingering in a Hele-Shaw cell
E. Melero-García, J.M. García-Ruiz, M. Kellermeier: Silica biomorphs: an aqueous precipitating
system “independent” of transport hydrodynamics
M. Mishra: Miscible viscous fingering of finite slices in three component systems
A. Puisto, M. Mohtaschemi, and M. J. Alava: Rheology changes in aggregating suspensions
M. Rogers: Heads and tails: The evolution of autocatalytic plumes and balls
B. Scheid: Surface-viscosity-induced thickening in liquid film coating
D. Sileri: Mathematical modelling of immiscible two-fluid flows in the presence of
phase changes, applied to He…
B. Thompson: Chemical Pattern Formation in Taylor-Couette Flow
P. Trevelyan: Viscous fingering of a miscible reactive A+B- > C interface: a linear stability analysis
C. Wylock: Experimental study of chemo-hydrodynamical instabilities during CO2 absorption in
basic solutions
64

Workshop on
“Chemo-hydrodynamic patterns and instabilities”
Scientific Programme
Wednesday 28 October 2009
08:15 - 09:00 Registration
Chemical reactions in complex flows
Chair : A. Pocheau (IRPHE)
09:00 - 09:10 Welcoming Address by A. De Wit
09:10 - 09:50 T. Solomon (Bucknell University)
Experimental studies of front propagation and pattern formation
in advection-reaction-diffusion systems
09:50 - 10:30 Z. Neufeld (University College Dublin)
Chemical and biological dynamics in prescribed chaotic
and turbulent flows
Workshops and Schools organised by the Institutes
10:30 - 11:00 Coffee Break
11:00 - 11:20 A. Tzella (Ecole Normale Supérieure)
Spatial structures of chaotically advected scalars: the role
of a delay time
11:20 - 11:40 H. Hastings (Hofstra University)
Mixing effects in the ferroin-catalyzed BZ:
reaction – physics versus chemistry
11:40 - 12:00 A. Munuzuri (Santiago de Compostela)
External convective forcings effects on patterning in reactiondiffusion
systems: experiments and theoretical studies
12:00 - 14:00 Lunch
Biological and microfluidic applications
Chair: S. Kalliadasis (Imperial College)
14:00 - 14:40 P. Tabeling (ESPCI, Paris)
Microfluidic droplet stories
14:40 - 15:20 J.-M. Garcia Ruiz (Universidad de Granada)
The role of fluid dynamics in protein crystallization
65

Workshops and Schools
organized by the Institutes
Scientific Programme
15:20 - 15:50 Coffee Break
15:50 - 16:30 M. Bees (University of Glasgow)
Bioconvection: instability and Taylor dispersion in a tube
16:30 - 16:50 J. Bois (Max Planck Institute for Physics of Complex Systems)
Polarity establishment in the one-cell C. elegans embryo as an
active reaction-diffusion-advection process
16:50 - 17:10 G. Guria (Moscow Institute of Physics and Technology)
Pattern Formation in Intensive Blood Flow
Thursday 29 October 2009
Convection around chemical fronts I
Chair: K. Eckert (Technische Universität Dresden)
09:00 - 09:40 S. Morris (University of Toronto)
Autocatalytic plumes
09:40 - 10:20 M. Hauser (Otto-von-Guericke- Universität Magdeburg)
Chemo-hydrodynamic convection in a system with an open surfaceP
10:20 - 10:50 Coffee Break
10:50 - 11:10 J. Merkin (Leeds University)
The interaction between buoyancy and diffusion- driven instabilities
of a propagating autocatalytic reaction front
11:10 - 11:30 A. Toth (University of Szeged)
Density fingering in horizontally propagating reaction fronts
11:30 - 12:10 N. Vladimirova (University of New Mexico)
Reactive Rayleigh-Taylor Instability in the Boussinesq Buoyancy
approximation
12:10 - 14:00 Lunch
66

Workshop on
“Chemo-hydrodynamic patterns and instabilities”
Convection around chemical fronts II
Chair: V. Pimienta (Université Paul Sabatier)
14:00 - 14:40 A. D’Onofrio (Universidad de Buenos Aires)
Buoyancy-driven instabilities of miscible reactions fronts with
double diffusion
14:40 - 15:00 A. Taylor (Leeds University)
Convection in pH fronts in reverse micelle systems
15:00 - 15:20 M. Sheintuch (Technion)
Transversal patterns in moving or oscillatory fronts of
advection-reaction-diffusion systems
15:30 - 17:30 Poster session
19:30 Banquet
Friday 30 October 2009
Workshops and Schools organised by the Institutes
Marangoni effects and reactive drops
Chair: U. Thiele (Loughborough University)
09:00 - 09:40 D. Quéré (Ecole Polytechnique Palaiseau)
On capillary propulsion
09:40 - 10:00 T. Ban (Doshisha University)
Chemical control of droplet motion
10:00 - 10:20 Y. Sumino (University of Tokyo)
Bebbling instability of oil droplet induced by growth/collapse
of elastic complex
10:20 - 10:50 Coffee Break
10:50 - 11:30 K. Eckert (Technische Universität Dresden)
Marangoni cells in interaction with chemical reactions in
liquid-liquid systems
67

Workshops and Schools
organized by the Institutes
Scientific Programme
11:30 - 11:50 V. Pimienta (Université Paul Sabatier, Toulouse)
Reactive autocatalytic transfer of surfactant leading
to Marangoni instability
11:50 - 12:10 J. Pojman (Louisiana State University)
Buoyancy-driven and interfacial-tension-driven convection
caused by polymerization
12:10 - 14:00 Lunch
Chemical réactions, fingering and instabilities in porous media and
Hele-Shaw cells
Chair: A. De Wit (ULB)
14:00 - 14:40 G. Desmet (VUB, Brussels)
Visualization and quantification of the onset and the extent of
viscous fingering in micro-pillar array columns for liquid
chromatography
14:40 - 15:00 Y. Nagatsu (Nagoya Institute of Technology)
Experiments on viscous fingering involving viscosity changes
due to chemical reactions
15:00 - 15:20 M. Kawaguchi (Mie University)
Path instabilities of bubbles in aqueous solutions in a Hele-Shaw cell
15:20 - 15:50 Coffee Break
15:50 - 16:30 M. Quintard (IMFT, Toulouse)
Reactive transport in porous media: multiple-scale analysis
and dissolution instabilities
16:30 - 16:50 D. Salin (FAST, Paris)
Autocatalytic reaction front: an active tracer for flow in fractures
68

Workshop on
“Chemo-hydrodynamic patterns and instabilities”
Workshops and Schools organised by the Institutes
69

Workshops and Schools
organized by the Institutes
List of Participants
Last Name First Name Institution
Adami Nicolas Université de Liège, Belgium
Al-Ghoul Mazen American University of Beirut, Lebanon
Almarcha Christophe Université Libre de Bruxelles, Belgium
Ban Takahiko Doshisha University, Kyoto, Japan
Basios Vasileios Université Libre de Bruxelles, Belgium
Beauvier Edouard Université d’Aix-Marseille, France
Boffetta Guido Università di Torino, Italy
Bois Justin Max-Planck-Institut für Physik komplexer
Systeme and Max-Planck-Institut für
Molekulare Zellbiologie und Genetik, Dresden, Germany
Boon Jean Pierre Université Libre de Bruxelles, Belgium
Britton Melanie Birmingham University, UK
Bronfort Ariane Université de Liège, Belgium
Bullara Domenico Université Libre de Bruxelles, Belgium
de Buyl Pierre Université Libre de Bruxelles, Belgium
Debenest Gérald Institut National Polytechnique de
Toulouse/IMFT, France
Dehaeck Sam Université Libre de Bruxelles, Belgium
Delil
Ad
Dorbolo Stéphane Université de Liège, Belgium
Dumazer Guillaume Universite Pierre et Marie Curie - Paris 6, France
Esposito Massimiliano Université Libre de Bruxelles, Belgium
Frastia Lubor Loughborough University, UK
Ganzevles
Frank
Gaponenko Yury Université Libre de Bruxelles, Belgium
Gilbert Thomas Université Libre de Bruxelles, Belgium
Glaab Fabian Universität Regensburg, Germany
Guria Georgy Moscow Institute of Physics and Technology
& National Reseach Center for Hematology, Russia
Hastings Harold Hofstra University, Moscow, Russia
Hennenberg Marcel Université Libre de Bruxelles, Belgium
Herman Christelle Université Libre de Bruxelles, Belgium
Homble Fabrice Université Libre de Bruxelles, Belgium
Jarrige Nolwenn Universite Pierre et Marie Curie - Paris 6, France
Kamrak Juthamas Université Libre de Bruxelles, Belgium
Kawaguchi Masami Mie University, Japan
Larcy Aurélie Université Libre de Bruxelles, Belgium
70

Workshop on
“Chemo-hydrodynamic patterns and instabilities”
List of Participants
Last Name First Name Institution
Maes Renaud Université Libre de Bruxelles, Belgium
Maes Dominique Vrije Universiteit Brussel, Belgium
Melero-Garcia Emilio Laboratorio de Estudios Cristalograficos (LEC), Armilla, Spain
Melnikov Denis Université Libre de Bruxelles, Belgium
Merkin John University of Leeds, UK
Mialdun Alexander Université Libre de Bruxelles, Belgium
Mikhailov Alexander Fritz-Haber-Institut der Max-Planck- Gesellschaft,
Berlin, Germany
Mishra Manoranjan Université Libre de Bruxelles, Belgium
Mocak Miroslav Université Libre de Bruxelles, Belgium
Munuzuri Alberto Universidad de Santiago de Compostela, Spain
Nagatsu Yuichiro Nagoya Institute of Technology, Japan
Perfetti Claire Université Libre de Bruxelles, Belgium
Pojman John Louisiana State University, Baton Rouge, USA
Pópity-Tóth Éva University of Szeged, Hungary
Puisto Antti Helsinki University of Technology, Finland
Pushkin Dmitri Université Libre de Bruxelles, Belgium
Rahal Naim Université Libre de Bruxelles, Belgium
Rogers Michael University of Toronto, Canada
Salin Dominique Universite Pierre et Marie Curie - Paris 6, France
Scheid Benoit Université Libre de Bruxelles, Belgium
Sheintuch Moshe Technion, Haifa, Israel
Shevtsova Valentina Université Libre de Bruxelles, Belgium
Siess Lionel Université Libre de Bruxelles, Belgium
Sileri Daniele Imperial College of London, UK
Sonnino Giorgio Université Libre de Bruxelles, Belgium
Sumino Yutaka University of Tokyo, Japan
Taylor Annette University of Leeds, UK
Thomas Gérard Université Libre de Bruxelles, Belgium
Thompson Barnaby University of Leeds, UK
Toth Agota University of Szeged, Hungary
Trevelyan Philip Université Libre de Bruxelles, Belgium
Tzella Alexandra Ecole Normale Superieure, Paris, France
Vantieghem Stijn Université Libre de Bruxelles, Belgium
Vetrano Maria Rosaria Von Karman Institute of Fluid Dynamics, R.-St-Genèse, Belgium
Viré Axelle Université Libre de Bruxelles, Belgium
Wylock Christophe Université Libre de Bruxelles, Belgium
71
Workshops and Schools organised by the Institutes

Modave Summer School
17 - 21 August 2009
73

Workshops and Schools
organized by the Institutes
The fifth edition of the Modave Summer School
in Mathematical Physics took place from the
17 th to the 21 st of August 2009.
The main goal of the school was to study mathematical
tools useful for research in theoretical
physics of fundamental interactions, generally
supposed to be known but too seldom explained
in details.
Organising Committee
Alice Bernamonti (VUB),
Cyril Closset (ULB),
Térence Delsate (UMH),
Ella Jamsin (ULB),
Wieland Staessens (VUB),
Walter Van Herck (K.U.Leuven),
Bert Vercnocke (K.U.Leuven).
Participants
Benichou Raphael
(ENS, Paris, France)
Bernamonti Alice
(VUB, Brussels, Belgium)
Closset Cyril
(ULB, Brussels, Belgium)
De Baetselier Iwein
(K.U.Leuven, Belgium)
De Rydt Jan
(K.U.Leuven, Belgium)
Dehouck François
(ULB, Brussels, Belgium)
Delsate Térence
(UMH, Mons, Belgium)
Galli Federico
(VUB, Brussels, Belgium)
Göteman Malin Wilhelmine
(Uppsala Universitet, Sweden)
Jamsin Ella
(ULB, Brussels, Belgium)
Kašpar Petr
(Charles University, Prague, Czech Republic)
Kim Sung-Soo
(ULB, Brussels, Belgium)
Lee Seung-Joo
(Oxford University, UK)
Lindman Hörnlund Josef
(ULB, Brussels, Belgium)
Mariotti Alberto
(VUB, Brussels, Belgium)
Montañez Naz Sergio
(ULB, Brussels, Belgium)
Palmkvist Jakob
(AEI, Potsdam, Germany)
Puhm Andrea
(Universität Wien, Austria)
Ruef Clement
(IPhT, Gif-sur-Yvette, France)
Staessens Wieland
(VUB, Brussels, Belgium)
Troessart Cédric
(ULB, Brussels, Belgium)
Van Herck Walter
(K.U.Leuven, Belgium)
Vercnocke Bert
(K.U.Leuven, Belgium)
Virmani Amitabh
(ULB, Brussels, Belgium)
Wijns Alex
(Nordita Institute, Stockholm, Sweden)
Zingg Tobias
(Nordita Institute, Stockholm, Sweden)
74

Modave Summer School
Workshops and Schools organised by the Institutes
75

Workshops and Schools
organized by the Institutes
Proposed lectures
o
o
o
o
o
o
Classification of fiber bundles, gauge theory and D-branes, Alex Wijns (6h)
Lie and Kac-Moody algebras, Jakob Palmkvist and Ella Jamsin (6h)
Black Holes: theorems, folklore, conjectures, and confusions, Amitabh Virmani (5h)
Two-dimensional conformal field theory and perturbative string theory, Raphaël Benichou (4h)
Aspects of supersymmetry breaking, Alberto Mariotti (4h)
Scattering amplitudes in string theory, Bert Vercnocke and Wieland Staessens (3h)
Modave 2009 was a complete success for me for multiple
reasons. First of all, and most important, is the fact
that this school is made “by students” and “for students”.
Indeed, the level of the seminars and their subjects is not
completely fixed by the organizers (as in other conferences)
but also discussed with the participants. Secondly,
the relatively small number of participants (about
30) makes it a wonderful place for discussions, elaboration
of future projects, interaction between participants
and speakers during and after the seminars. This school
is also interesting for us, students, because it gives the
opportunity to be lecturer and receive feedbacks from
other students. Finally, it is a week to learn from students
of about the same level, coming from all around
Belgium and abroad, about their current research in
theoretical physics.
François Dehouck,
PhD student, ULB, Belgium.
Organized by young researchers for young researchers,
the Modave summer school in mathematical
physics provides a venue where advanced, interesting
topics in theoretical physics and mathematics can be
discussed in an informal and pedagogical way.
This was what I found most appealing about the school,
when I first heard about it. Add to this, that the school is
situated in a picturesque village in the beautiful mountains
in the south of Belgium, and that it gives an opportunity
to get to know other young researchers in the field
– I realized I definitely had to go there.
And the school did by far meet up to my expectations.
The relaxed atmosphere, the excellent lectures and the
nice participants made it a great experience. Also, the
nearby castle and the local pub were well worth a visit
when a break from physics and maths was needed. If
I get the chance, I will participate in the school every
summer from now on!
Malin Göteman, PhD student,
Upsalla University, Sweden.
76

Modave Summer School
Workshops and Schools organised by the Institutes
77

“Quantum Field Theory, Strings and Gravity”
The International
Doctoral School
“Quantum Field
Theory, Strings
and Gravity”
21 September - 9 October 2009
The International Doctoral School
79

The International Doctoral School
This school was organized for the fourth consecutive year in the fall of 2009 by the International
Solvay Institutes and the Service de Physique Théorique et Mathématique at U.L.B., the Theoretical
Particle Physics group at V.U.B, the Laboratoire de Physique Théorique at École Normale Supérieure
in Paris and the Institute for Theoretical Physics in Amsterdam. Each of the organizing sites
(Brussels, Paris and Amsterdam) welcomed the students for intense three-week sessions separated
by one-week breaks.
The participants were all beginning graduate students, from the organizing nodes and also from various
other institutions in France, the Netherlands and Belgium. All the students followed more than
250 hours of lectures organized in various courses. The main goals were to strengthen their training
in quantum field theory and string theory and to introduce them to cutting-edge research problems
in the field. In Brussels, the programme was made up of an Advanced Quantum Field Theory course
by Prof. Adel Bilal (30 h), an introduction to String Theory by Prof. Elias Kiritsis (24 h), classes on
General Relativity, Cosmology and Black holes by Prof. Veronika Hubeny (24 h) and a series of
lectures by Prof. Valery Rubakov on Cosmology and the theory of inflation (9 h).
This programme is unique in Europe. It provides a great opportunity for the students to be introduced,
at an unusually early stage in their training, to the “Big Picture” of a highly technical field
that covers large areas of Physics and Mathematics. The possibility to meet leading experts in an
informal setting and to share research interests and insights with fellow graduate students from other
countries, which may become long-term collaborators after their PhD study, is also a great asset of
the School.
In Brussels, the School greatly benefits from the assistance of the International Solvay Institutes.
Beyond a sizeable financial support, the lectures delivered by the holder of the Solvay Chair in
Physics (Prof. Rubakov in 2009) are included into the curriculum.
The School has now reached maturity, with an excellent organization, thoroughly chosen topics
and a smooth transition between the trainings offered at the different nodes. All the participants
seem extremely enthusiastic about this programme and we are looking forward to welcoming the
students next year.
Frank Ferrari
80

“Quantum Field Theory, Strings and Gravity”
The Brussels Organising
Committee
Scientists
Riccardo Argurio (ULB)
Ben Craps (VUB)
Frank Ferrari (ULB)
Logistics support
Isabelle Juif (ULB & Solvay Institutes)
Topics covered in 2009
Programme Brussels 2009
o String Theory - Elias Kiritsis (Crete)
o Advanced Quantum Field Theory - Adel Bilal
(ENS)
o General Relativity, Cosmology and Black
Holes - Veronika Hubeny (Durham)
o Cosmology and Theory of Inflation - Valery Rubakov
(Institute for Nuclear Research, Moscow)
The International Doctoral School
In Brussels: String theory - Advanced Quantum
Field Theory - General Relativity, Cosmology
and Black Holes - Inflation
In Paris: Effective field theories in the standard
model and beyond - Beyond the standard
model physics - Introduction to supersymmetry
- Introduction to AdS/CFT - Introduction to
Supergravity
In Amsterdam: String cosmology - Advanced
string theory - Supersymmetric gauge theory
- Advanced GR & Black holes in string theory -
Gauge/gravity duality
Participating Institutions
Institute for theoretical physics - Universiteit van
Amsterdam - the Netherlands
Laboratoire de physique théorique - Ecole
Normale Supérieure (Paris) - France
Physique théorique et mathématique, ULB /
Theoretical particle physics, VUB (Brussels) -
Belgium
81

The International Doctoral School
The opinion of a student (by Antonin Rovai,
PhD student at ULB)
This school gave me a good opportunity to
complement my knowledge of various fundamental
topics and also to discover entire fields
of research: string theory, beyond the standard
model physics, supergravity theories, cosmology,
etc…
It was also an excellent opportunity to meet
other first year PhD students from all across
Europe.
Some lectures had some overlap with my
previous training, like in Quantum Field
Theory, String Theory or General Relativity, but
were nevertheless very instructive thanks to the
in-depth treatments of the subjects and/or the
original points of view of the lecturers.
Other lectures covered topics that were completely
new to me (e.g. AdS/CFT, supergravity,
string cosmology). These lectures were the
hardest to follow, since a large background of
knowledge was often assumed, and generally
lecture notes were not available. In some
cases we only got a broad overview of the
subject. Sometimes, the lecturers were also
organising very useful exercise and discussion
sessions. These also prompted the students
to work together, which was a very positive
experience.
Another enjoyable aspect of the school was
the ability to visit new Physics departments and
discover new research areas. In Amsterdam,
we were also able to attend a one-day conference
with several research seminars, which
was a new and interesting experience.
82

Participants
“Quantum Field Theory, Strings and Gravity”
Baggio Marco
(Universiteit van Amsterdam, the Netherlands)
Bzowski Adam
(Universiteit van Amsterdam, the Netherlands)
Coomans Frederik
(K.U.Leuven, Belgium)
Coutant Antonin
(ENS Lyon, France)
de Aquino Priscila
(K.U.Leuven & U.C.Louvain, Belgium)
Farmer Benjamin
(Monash University, Australia)
Hardeman Sjoerd
(Universiteit Leiden, the Netherlands)
Hatefi Ehsan
(Ferdowsi University of Mashad, Iran)
Hristov Kiril
(Utrecht Universiteit, the Netherlands)
Meunier Elisa
(Université François Rabelais, Tours, France)
Ohlsson Fredrik
(Chalmers University of Technology, Sweden)
Peng Zongren
(Université Paris 6, France)
Rovai Antonin
(Université Libre de Bruxelles, Belgium)
Tempo José David
(Universidad de Concepcion, Chile and Université
Libre de Bruxelles, Belgium)
Van de Rijt Nicolas
(Institut de Physique Théorique, CEA, Saclay,
France)
Van der Veken Frederik
(VUB, Brussels, Belgium)
van Tongeren Stijn
(Utrecht Universiteit, the Netherlands)
Wouters Bram
(University of Cambridge, UK)
The International Doctoral School
83

Colloquia
Colloquia
85

Colloquia
Graphene: Magic of Flat Carbon
Professor Andre GEIM
University of Manchester, UK
27 January 2009
Abstract
Graphene is a free-standing atomic-scale
chicken wire made from carbon. It is one
atom thick and the first truly two dimensional
crystal. Found only five years ago, it has
rapidly become one of the brightest stars
on the horizon of materials science and
condensed matter physics, signifying a new
paradigm of two dimensional materials that
are now available for fundamental studies
and development of novel technologies.
Graphene has already revealed a cornucopia
of new physics and, in addition,
promises many applications that start looking
increasingly realistic. I will overview our
experimental work on graphene concentrating
on its fascinating electronic and optical
properties and speculate about future applications.
86

Colloquia
Organic semiconductors: a new generation
of materials for opto-electronic devices
Professor Jean-Luc BRÉDAS
Georgia Institute of Technology, USA
17 March 2009
Abstract
Conjugated organic oligomer and polymer
materials are being increasingly considered
for incorporation as active semiconductor
elements in devices such as photo-voltaic
(solar) cells, light-emitting diodes, or fieldeffects
transistors.
In this presentation, we first illustrate some
of the most promising applications of conjugated
organic materials. We then describe
the basic operation of a device such as an
organic solar cell or light-emitting diode. In
the last part, based on a molecular/microscopic
standpoint, we discuss the various
parameters that impact charge separation or
harge-carrier mobilities in such devices and
highlight the contributions of computational
chemistry in the design of more efficient
materials.
87

Colloquia
From structure to function: Chemistry in transition
Professor Alexander S. MIKHAILOV
Fritz-Haber-Institut der Max-Planck-Gesellschaft,
Berlin, Germany
21 April 2009
Abstract
Traditional physical chemistry has been
focused on explaining structural properties
of individual chemical objects and elementary
reaction events involving them. Today,
we realize that this knowledge is far from
sufficient to understand the known complex
chemical systems. Not only in the realm
of biology, but even for classical reactions
of heterogeneous catalysis, emergence of
coherent collective behavior – often yielding
the ultimate function of a chemical system –
is a process that needs to be understood. In
this lecture, I provide a personal overview
of the developments in studies of chemical
self-organization phenomena in the last
decades and discuss some trends of future
research.
88

Colloquia
The cosmic microwave background as a probe
of the very early universe
Professor Eiichiro KOMATSU
University of Texas at Austin, USA
12 May 2009
Abstract
The Cosmic Microwave Background (CMB),
the fossil light of the Big Bang is the oldest
light that one can ever hope to observe in
our Universe. The CMB provides us with a
direct image of the Universe when it was
still an “infant” - 380,000 years old and
has enabled us to obtain a wealth of
cosmological information, such as the
composition, age, geometry, and history
of the Universe. Yet, can we go further and
learn about the primordial universe, when
it was much younger than 380,000 years
old, perhaps as young as a tiny fraction
of a second? If so, this gives us a hope to
test competing theories about the origin of
the Universe at ultra high energies. In this
talk I review the present status and future
prospects on our quest to probe the physical
condition of the very early Universe.
89

Colloquia
Particle physics and cosmology:
towards understanding the universe
Professor Valery RUBAKOV
Institute for Nuclear Research of the Russian
Academy of Sciences, Moscow, Russia
29 September 2009
Abstract
Knowledge gained so far in cosmology
is to a large extent orthogonal to current
knowledge in particle physics. There is
matter and no anti-matter in our Universe,
and we do not have a unique explanation
of this asymmetry. There is dark matter
in the cosmos, and we do not know what
the particles are it consists of. Cosmological
expansion accelerates, and we do not
know the fundamental physics behind this
bizarre behavior. The origin of galaxies must
have roots deep in quantum field theory, but
we still have only a crude idea of what they
are. Amazingly, all these mysteries will most
probably be solved in a reasonably near
future. I review these and other issues at the
interface of particle physics and cosmology,
with an emphasis on future progress in our
understanding of the Universe.
90

Colloquia
Quantum phase transitions: from antiferromagnets
and superconductors to black holes
Professor Subir SACHDEV
Harvard University, Cambridge, USA
27 October 2009
Abstract
I will describe basic features of the theory
of quantum phase transitions, and discuss its
application to recent experiments on insulating
antiferromagnets and on the cuprate
superconductors. I will also note the remarkable
connections between these theories
and the quantum theory of black holes.
91

Colloquia
Dark matters
Professor Joe SILK
University of Oxford, UK
24 November 2009
Abstract
One of the greatest mysteries in the cosmos
is that it is mostly dark. That is, not only is
the night sky dark, but also most of the matter
in the universe is dark. For every atom
visible in planets, stars and galaxies today
there exists at least five or six times as much
``Dark Matter’’ in the universe. Astronomers
and particle physicists today are seeking
to unravel the nature of this mysterious, but
pervasive dark matter which has profoundly
influenced the formation of structure in the
universe. I will review various attempts to
measure dark matter by direct and indirect
means.
92

Colloquia
Exploring the interface between
heterogeneous and homogeneous catalysis
Sir John Meurig THOMAS
University of Cambridge, UK
15 December 2009
Abstract
Recent advances in structural characterization
have prompted many students of catalysis
to argue that the distinctions between heterogeneous
and homogeneous catalysts are
becoming increasingly burred. The situation
has further prompted certain investigators to
enunciate the following statements, each of
which will be adumbrated during the course
of the talk:
1 - The scope for introducing multifunctional
catalysis is greater with heterogeneous than
with homogeneous catalysts.
2 - The nature of active sites in homogeneous
and heterogeneous catalysts is very
different.
3 - Certain chemical transformations can be
effected efficiently only with heterogeneous
catalysts.
4 - Many homogeneous catalysts may be
immobilized at the surfaces of, or intercalated
within, solids and often yield superior
performance.
5 - Spatially isolated and readily accessible
single-sites on nanoporous supports unite the
advantages of heterogeneous and homogeneous
catalysts.
93

Institutional
Collaborations
Institutional Collaborations
95

Institutional Collaborations
In 2004, the International Solvay Institutes signed collaboration agreement with the Centro de Estudios
Científicos (Valdivia, Chile) and in 2005 with the Lebedev Physical Institute (Moscow, Russia).
These collaborations favor scientific exchange of visitors between Belgium and Chile or Russia of
scientists affiliated with the signing institutions or with neighboring ones and working in similar areas.
Both collaborations were very active in 2009.
Cooperation with the Centro de Estudios
Científicos (Valdivia, Chile)
Visits of Belgian Scientists to Chile
Professor Glenn Barnich
26 January - 4 February 2009
François Dehouck
7-11 December 2009 (Summer School in Frutillar)
11-16 December 2009
Professor Marc Henneaux
7-21 January 2009; 4-14 August 2009;
7-24 December 2009
Visits of Chilean Scientists to Belgium
Professor Max Bañados
11-17 May 2009; 9-13 November 2009
Joint publications
C. Bachas, C. Bunster and M. Henneaux,
“Dynamics of Charged Events,” Phys. Rev. Lett.
103 (2009) 091602 [arXiv:0906.4048 [hep-th]].
M. Henneaux, C. Martinez and R. Troncoso,
“Asymptotically anti-de Sitter spacetimes in
topologically massive gravity,” Phys. Rev. D 79
(2009) 081502 [arXiv:0901.2874 [hep-th]].
M. Henneaux and J. Zanelli editors of
“Quantum Mechanics of Fundamental Systems:
The Quest for Beauty and Simplicity”, Springer
(New York: 2009).
Professor Claudio Bunster
22-28 August 2009
Professor Andrés Gomberoff
1-14 July 2009
Professor Cristián Martínez
19-30 April 2009
M. David Tempo
15 September - 8 December 2009
(“these en co-tutelle” with the ULB).
Professor Riccardo Troncoso
19-30 April 2009
96

Cooperation with the Lebedev Physical Institute
(Moscow, Russia)
Visits of Belgian Scientists to Russia
Professor Glenn Barnich
18 May - 23 May 2009
Visits of Russian Scientists to Belgium
Professor Igor Batalin
29 November - 18 December 2009
Professor A. Belavin
March 2009
Joint publications
G. Barnich and M. Grigoriev
“A Poincare lemma for sigma models of
AKSZ type,” arXiv:0905.0547 [math-ph].
Xavier Bekaert and Maxim Grigoriev
“Manifestly conformal descriptions and
higher symmetries of bosonic singletons”,
arXiv:0907.3195v2 [hep-th] 6 Nov 2009.
Institutional Collaborations
Professor Maxim Grigoriev
25 May - 10 June 2009
29 November - 18 December 2009
Professor Valéry Rubakov
15 September - 31 October 2009
97

Noncommutative Structures in Mathematics and Physics,
A satellite Conference to the Fifth European Congress
of Mathematics
Conference
sponsored
by the Institutes
2 - 4 September 2009
Conference sponsored by the Institutes
99

Conference sponsored by the Institutes
Lecturers
Henri Berestycki
(Paris)
Djairo G. de Figueiredo
(Campinas)
Francois de Thélin
(Toulouse)
Pavel Drabek
(Pilsen)
Jesús Hernández
(Madrid)
Bernd Kawohl
(Köln)
Pierre-Louis Lions
(Paris)
Jean Mawhin
(Louvain-la-Neuve)
Petru Mironescu
(Lyon)
Mark Peletier
(Eindhoven)
Frederic Robert
(Nice)
Julio Daniel Rossi
(Buenos Aires)
Bernhard Ruf
(Milano)
Michael Struwe
(Zürich)
Charles Stuart
(Lausanne)
Juan Luis Vazquez
(Madrid)
Session Organizers
o Geometry and PDEs
A. Ponce (UCL) and J. Van Schaftingen
(UCL)
o On the Fucik spectrum
M. Arias (UGR), J. Campos (UGR) and
M. Cuesta (ULCO)
o On the p-Laplacian with 1 < p ≤ ∞
J. Fleckinger-Pellé (UT1), F. de Thelin (UT1)
and P. Takac (uni-rostock)
Committees
Local board
Denis Bonheure (ULB)
Ann Derlet (ULB)
Paul Godin (ULB)
Enrique Lami Dozo (ULB)
Pieter de Groen (VUB)
Christophe Troestler (UMH)
Advisory board
Margarita Arias (UGR)
Juan Campos (UGR)
Mabel Cuesta (ULCO)
Jacqueline Fleckinger-Pellé (UT1)
Augusto Ponce (UCL)
Peter Takác (Univ. Rostock)
Jean Van Schaftingen (UCL)
Michel Willem (UCL)
100

Workshop in Nonlinear Elliptic PDEs
A celebration of Jean-Pierre Gossez’s 65th birthday
Conference sponsored by the Institutes
101

102

Noncommutative Structures in Mathematics and Physics,
A satellite Conference to the Fifth European Congress
of Mathematics
5 th Flemish Space Days
5 th Flemish
Space Days
Vijfde Vlaamse
Ruimtevaartdagen
8 - 10 May 2009
103

5 th Flemish Space Days
Vijfde Vlaamse Ruimtevaartdagen
The contribution of the research group ”Astrophysics”
from the Vrije Universiteit Brussel
was made in collaboration with Franz Bingen.
He composed the posters in connection to the
famous Solvay Conferences where all the giants
of physics (Albert Einstein and many others)
presented their theories to the world.
The three posters from the research group
”Astrophysics” were made by Walter van Rensbergen
in collaboration with Nicky Mennekens
and Jean-Pierre de Greve. One poster showed
that astronomical observations made out of the
earth atmosphere have opened an entirely new
view on the universe. The images being much
more precise and the entry into wavelengths
which are absorbed by the earth atmosphere.
The second poster explained the detection of
gamma ray bursters by techniques which are
available by space research only. The most
energetic phenomena known to mankind would
have been obscured without the use of space
research. The third poster focussed on the efforts
of the European Space Agency (ESA) to contribute
to the advancement of knowledge. With
”GAIA” distances up 25.000 parsec will be
determined. This means that ”GAIA” will be able
to measure an angle as small as one second of
arc divided by 25.000. ”DARWIN” will search
for habitable planets in our milky way.
104

105
5 th Flemish Space Days

5 th Flemish Space Days
Vijfde Vlaamse Ruimtevaartdagen
106

107
5 th Flemish Space Days

108

Seminars

Seminars
Gravity and hydrodynamics, Mukund
Rangamani (University of Durham, UK) –
4 February 2009.
Brownian motion in AdS/CFT, Mukund
Rangamani (University of Durham, UK) –
4 February 2009.
Contrasting confinement in superconductors and
superQCD, Jarah Evslin (SISSA, Trieste, Italy) –
6 February 2009.
Astrophysical probes of fundamental physics:
from alpha to omega, Carlos Martins
(U Porto, Portugal) – 6 February 2009.
3D gravity theories, exact string backgrounds
and applications, Stéphane Detournay
(UCSB, Santa Barbara, USA) –
16 February 2009.
Adding massive dynamical quarks to the gauge/
string correspondence, Francesco Bigazzi
(ULB, Belgium) – 18 February 2009.
The return of the phoenix universe, Jean-Luc
Lehners (Princeton University, USA) –
18 February 2009.
Holographic gluon plasma from 5d dilatongravity,
Liuba Mazzanti (Università di Milano-
Bicocca, Italy and Ecole Polytechnique,
Palaiseau, France) – 25 February 2009.
Deformed gauge theories and their string duals,
Emiliano Imeroni (ULB, Belgium) – 4 March 2009.
Conformal current algebra in two dimensions,
Raphaël Benichou (ENS, Paris, France) –
4 March 2009.
2-Dimensional Minimal Gravity in Matrix
Model and Liouville approaches, A. Belavin
(Landau Institute for Theoretical Physics, Russia)
– 6 March 2009.
Cosmological perturbations in non-local SFT
cosmological models, Alexey Koshelev (VUB,
Belgium) – 11 March 2009.
Quantizing N=2 Multicenter Solutions,
Sheer El-Showk (Universiteit van Amsterdam,
the Netherlands) – 11 March 2009.
N=1 supergravity with Chern-Simons terms and
anomaly cancellation, Jan De Rydt (K.U.Leuven,
Belgium) – 18 March 2009.
Orientiholes: black hole technology applied to
flux vacua, Mboyo Esole (Harvard University,
USA) – 18 March 2009.
Top anomalous couplings in single top production,
Priscila De Aquino (K.U.Leuven, Belgium)
– 25 March 2009.
Galois symmetries in Super Yang-Mills Theories,
Frank Ferrari (ULB, Belgium) – 25 March 2009.
Gravitational instantons, Ricci flows and
integrable structures, Marios Petropoulos
(CPHT-Polytechnique, France) – 1 April 2009
.
110

Seminars
Simplicity in the Structure of N=8 Supergravity
Amplitudes, Pierre Vanhove (CEA-Saclay and
IHES, France) – 1 April 2009.
Canonical Transformations and the Algebra
of Physical Observables in Nonlinearly
Realized Gauge Theories, Andrea Quadri
(Milano, Italy) – 14 April 2009.
Conformally supersymmetric Wilson loops in
N=4 super Yang-Mills, Vasily Pestun (Harvard
University, USA) – 22 April 2009.
Large D-instanton effects in string theory, Stefan
Vandoren (Universiteit Utrecht, the Netherlands)
– 22 April 2009.
Localization in the N=2 and N=4 super Yang-
Mills gauge theory and Wilson loops, Vasily
Pestun (Harvard, USA) – 23 April 2009.
Hidden symmetries as a black hole solution
generating technique, Ella Jamsin (ULB,
Belgium) – 29 April 2009.
D-brane Inflation in String Theory,
Anatoly Dymarsky (Stanford University, USA) –
29 April 2009.
Three dimensional massive gravity,
Gaston Giribet (University of Buenos Aires &
CONICET, Argentina) – 5 May 2009.
On-shell methods in gauge theory and gravity,
Andreas Brandhuber (Queen Mary, UK) –
6 May 2009.
Hidden structures in gauge theory and gravity,
Andreas Brandhuber (Queen Mary, UK) – 6
May 2009.
Dark matter interpretation of the Pamela
and Fermi results: theoretical trends, Thomas
Hambye (ULB, Belgium) – 20 May 2009.
Lattice simulation of thermal D0-branes,
Toby Wiseman (Imperial College, UK) –
20 May 2009.
Donaldson-Thomas partitions and refined bound
state indices, Walter Van Herck (K.U.Leuven,
Belgium) – 27 May 2009.
Susy and the brane: A σ model story, Wieland
Staessens (VUB, Belgium) – 27 May 2009.
Local Conformal Symmetry and its Violation
at Quantum Level, Ilya L. Shapiro (Universidade
Federal de Juiz de Fora, MG, Brazil) –
2 June 2009.
Black Holes and the Structure of Spacetime,
Maulik Parikh (IUCAA, India) – 3 June 2009.
Testing String Theory with Cosmological Observations,
Robert Brandenberger
(McGill University, Canada) – 3 June 2009.
Modular Differential Equations and Null
Vectors in RCFTs, Anindya Dey
(University of Texas, Austin, USA) –
29 June 2009.
111

Seminars
Renormalization group in Lifshitz-type theories,
Marco Serone (SISSA, Italy) –
7 October 2009.
Why not a NUT story?,François Dehouck
(ULB, Belgium) – 7 October 2009.
Universal Phenomena in Strongly Coupled
Gauge Theories and Gravity,
Ayan Mukhopadhyay (Harish-Chandra
Research Institute, India) – 9 October 2009.
Half BPS Supergravity Solutions and
Superalgebras, Darya Krym (K.U.Leuven, Belgium)
– 14 October 2009.
M2-branes, triple systems and superalgebras,
Jakob Palmkvist (ULB, Belgium) – 14 October
2009.
N=8 supergravity: back to the future,
Hermann Nicolai (Albert Einstein Institute,
Germany) – 15 October 2009.
Comments on Supersymmetry and Inflation, Luis
Alvarez-Gaumé (CERN, Switzerland) –
21 October 2009.
Topology of gauge fields and anomalous
baryon number non-conservation, Valery
Rubakov (Institute for Nuclear Research, Moscow,
Russia) – 21 October 2009.
Strong coupling problems in condensed matter
and the AdS/CFT correspondence, Subir Sachdev
(Harvard, USA) – 26 October 2009.
Multi-Trace Deformations of AdS/CFT and
Spherical D-Branes, Alice Bernamonti
(VUB, Belgium) – 28 October 2009.
Tensor Hierarchies and Supergravities,
Jelle Hartong (Universität Bern , Switzerland) –
28 October 2009.
Spontaneous partial supersymmetry breaking in
supergravity, Paul Smyth (Hamburg, Germany) –
4 November 2009.
Moduli fixing in asymmetric heterotic orbifold,
Cristina Timirgaziu (Liverpool, UK) – 4 November
2009.
Massive gravity in 3d and 4d. Bigravity formulations
and some applications, Max Bañados
(Pontificia Universidad Católica de Chile) –
10 November 2009.
Bound States of M-theory, Paul P. Cook (King’s
College London, UK) – 12 November 2009.
Phase diagram for non-axisymmetric plasma
balls, Jorge Rocha (Instituto Superior Técnico,
Lisbon, Portugal) – 17 November 2009.
Instabilities and new phases of higher-dimensional
rotating black holes, Pau Figueras (University
of Durham, UK) – 18 November 2009.
N=2 Chern-Simons matter theories: RG flows
and IR behavior, Silvia Penati (Università di
Milano-Bicocca , Italy) – 18 November 2009.
112

Seminars
A flavour superconductor from string theory,
Johanna Erdmenger (MPI München, Germany)
– 25 November 2009.
Stringy instaton calculus,Marco Billò (Università
di Torino, Italy) – 25 November 2009.
Large N duality beyond the genus expansion,
Sara Pasquetti (CERN, Switzerland) –
2 December 2009.
Holographic Flavor Transport, Andy O’Bannon
(MPI München, Germany) –
2 December 2009.
A light scalar from walking solutions in gaugestring
duality, Daniel Elander (Swansea University,
UK) – 9 December 2009.
M5-branes wrapped on Riemann surfaces,
Francesco Benini (Princeton, USA) –
16 December 2009.
Non-Gaussian constraints on excited states in
effective field theories of inflation, Jan Pieter
van der Schaar (UvA, the Netherlands) –
16 December 2009.
Quantum aspects of black holes, Joan Simon
(University of Edinburgh, UK) –
9 December 2009.
113

114

Research Interests of some Members
Research on
Gravitation,
Strings and
Cosmology
Groups of Professors
Marc Henneaux (ULB)
and Alexander Sevrin (VUB)
Research on Gravitation, Strings and Cosmology
115

Research on Gravitation, Strings and Cosmology
Permanent Members
Riccardo Argurio
(ULB)
Glenn Barnich
(ULB)
Ben Craps
(VUB)
Frank Ferrari
(ULB)
Marc Henneaux
(ULB)
Thomas Hertog
(APC Paris)
Laurent Houart
(ULB)
Axel Kleinschmidt
(ULB)
Alexander Sevrin
(VUB)
Postdoctoral Members
Raphael Benichou
(VUB)
Francesco Bigazzi
(ULB)
Neil Copland
(VUB)
Oleg Evnin
(VUB)
Emiliano Imeroni
(ULB)
Sung-Soo Kim
(ULB)
Semyon Klevtsov
(ULB)
Alexey Koshelev
(VUB)
Chethan Krishnan
(ULB)
Stanislav Kuperstein
(VUB)
Carlo Maccaferri
(ULB)
Alberto Mariotti
(VUB)
Sergio Montañez
(ULB)
Jakob Palmkvist
(ULB)
Amitabh Virmani
(ULB)
116

Graduate Students
Alice Bernamonti
(VUB)
Cyril Closset
(ULB)
François Dehouck
(ULB)
Frederik De Roo
(VUB)
Federico Galli
(VUB)
Ella Jamsin
(ULB)
Josef Lindman Hörnlund
(ULB)
Daniel Persson
(ULB)
Antonin Rovai
(ULB)
Wieland Staessens
(VUB)
Nassiba Tabti
(ULB)
Dimitri Terryn
(VUB)
Cedric Troessaert
(ULB)
Vincent Wens
(ULB)
Researchers
Research on Gravitation, Strings and Cosmology
117

Research on Gravitation, Strings and Cosmology
Research Summary
Of all the fundamental forces (electromagnetism,
gravitation, weak and strong nuclear forces),
gravity remains the most mysterious. In spite
of its remarkable successes, Einstein’s general
theory of relativity, which has led to an unprecedented
geometrization of physics, is an unfinished
revolution. The group has a long-standing
interest in quantum gravity, quantum field theory,
string theory and M-theory, black holes, cosmology,
the cosmological constant problem (“dark
energy”) and the novel mathematical structures
underlying these questions.
A central thread in the study of gravity and the
fundamental interactions is the concept of symmetry
(global and local). Some of the general
background is given below.
General framework
The standard model of particle physics is based
on quantum field theory, a framework that
reconciles Poincaré invariance with quantum
mechanics and allows one to understand the
electromagnetic and the two types of nuclear
interactions. The fourth fundamental interaction,
gravitation, is described by Einstein’s theory of
general relativity. Experiments as well as theoretical
arguments indicate that neither the standard
model, nor general relativity can be complete.
Purely theoretical attempts at generalizations
are constrained, of course, by mathematical
consistency and the need to incorporate the previous
theories in the domains where they have
been successful. Additional guiding principles
are needed, though. Symmetry is such a principle
and pervades most of the research carried
out in theoretical high energy physics.
The Yang-Mills type theories for the three microscopic
forces of elementary particle physics are
invariant under Poincaré symmetries, the symmetry
group of flat space-time. These theories admit
in addition certain internal symmetries known as
gauge symmetries. In general relativity, gravitation
arises when going from a flat to a curved
spacetime, and Poincaré symmetries become
part of the gauge group of diffeomorphisms.
In models that go beyond the existing theories,
other symmetries come to the front.
118

Supersymmetry
Supersymmetry is a natural extension of Poincaré
symmetry in the presence of fermionic
matter fields. Supersymmetric extensions of the
standard model will be tested at the experiments
planned in the Large Hadron Collider at CERN
in Geneva.
Supersymmetry is also an important ingredient
of string theory, a model for unification of the
four fundamental interactions and for a microscopic
formulation of gravity. At low energy,
higher dimensional theories of gravitation
emerge that include supersymmetry as part of
their gauge group together with supersymmetric
extensions of Yang-Mills gauge theories.
Hidden symmetries
Hidden symmetries in gravity and string theory
arise in compactifications of supergravity theories
and among the string duality groups. The
algebraic structure of these symmetries is related
to infinite-dimensional Lorentzian Kac-Moody
algebras, in particular those of E 10
and E 11
.
Research carried out in 2008
Research Summary
We have continued our research along the
general directions outlined above. This has led
to 70 published papers and preprints submitted
for publication. These are listed below. Specific
achievements by some researchers from the
group are also described in the subsequent
pages.
Research on Gravitation, Strings and Cosmology
Dualities
One of the first theoretical extensions of Maxwell’s
theory of electromagnetism has been the
inclusion of magnetic sources. The introduction
of such sources is motivated by the desire to
preserve invariance under duality rotations, a
symmetry of the source-free equations. The solution
that is dual to the Coulomb solution describing
a static point-particle electron is a magnetic
monopole. In some sense, black hole solutions
in gravitational theories are the analog of the
Coulomb solution to Maxwell’s theory.
In nonlinear theories like Yang-Mills theories,
dualities relate a strongly coupled regime to one
at weak coupling, where standard perturbative
computations may be performed. In supersymmetric
situations, these dualities become tractable.
Finally, dualities between different string
theories as well as holographic duality between
gauge and gravity theories feature prominently
in most of the recent developments in string
theory.
119

Research on Gravitation, Strings and Cosmology
Glenn Barnich (ULB)
Research Director, Fund for Scientific
Research-FNRS (Belgium)
Independently of the question whether string
theory in its current form is ultimately viable as
a realistic model for quantum aspects of the
gravitational interaction and as a theory capable
of unifying the fundamental interactions,
it seems legitimate to try to use the wealth of
ideas, techniques and mathematical results that
have been developed in more minimalistic and
well tested theories.
In this sense, a major aim of my current research
is a better understanding of the role
played by improper gauge degrees of freedom
in the context of black hole thermodynamics,
gravitational dualities and holography.
Surface charges and the Kerr/CFT correspondence
Motivated by the use that had been made
by Strominger of the Brown-Henneaux central
charge in asymptotically anti-de Sitter gravity
in three dimensions – he argued for a microscopic
explanation of the Bekenstein-Hawking
entropy of the BTZ black hole – we had
elaborated a covariant theory for surfaces
charges, their algebra and central extensions
in collaboration with Friedemann Brandt in
2001.Consequences and applications of this
approach have then been studied in a series of
subsequent papers with Geoffrey Compère in
particular.
This development has now gone full circle
since Strominger and coworkers have used
our formalism to give similar arguments for the
entropy of an extreme four dimensional black
hole which is potentially of direct astrophysical
interest..
Dualities in linearized gravity and higher
spin gauge theories
Together with Andrés Gomberoff, we have
improved the manifestly duality invariant
for- mulation of electromagnetism in the presence
of electric and magnetic sources through
additional gauge degrees of freedom. In the
new formulation, the spectrum of standard
electromagnetism, which contains besides the
physical degrees of freedom a non phys- ical
quartet consisting of temporal and longitudinal
photons with their ghost partners, is extended
by another non physical quartet. As a consequence
electric and magnetic fields no longer
have Dirac-type string singularities and a static
dyon is described by Coulomb-type potentials.
By coupling this version of electromagnetism
to gravity, the thermodynamics of black hole
dyons has been shown to follow from standard
arguments and electric-magnetic back
hole duality is manifest in the grand canonical
ensemble.
When extending this construction to spin 2
fields with Cédric Troessaert, an unexpected
new result has emerged: it turns out that in
linearized gravity with enhanced gauge
invariance, there is both an electric and a
magnetic copy of surface charges that transform
under global Poincaré transformations.
The natural question to ask is then whether
there are also two copies of Poincaré symmetries.
This would mean two time translations
and thus two Hamiltonians. We were able to
answer this question in the following sense:
in the reduced phase space description, electromagnetism,
linearized gravity and massless
higher spin fields are all bi-Hamiltonian
systems, the duality generator playing the role
of the second Hamiltonian generator for the
same Hamiltonian flow in a new, simplified
120

Research Interests of some Members
Research on Gravitation, Strings and Cosmology
Poisson bracket structure. This intriguing result
hints to connections with integrable sys- tems.
The major drawback of our current understanding
is that it holds merely for the linearized
theories. To make it really interesting one
would need to find interactions that preserve
this structure.
Three dimensional gravity and the quantum
mechanics of improper gauge degrees of
freedom
Due to the absence of bulk degrees of freedom,
gravity in three dimensions is made up
exclusively of improper gauge degrees of
freedom, i.e., gauge degrees of freedom that
cease to be pure gauge because of non-trivial
boundary conditions, topology or sources.
£The quantum mechanics of these degrees of
freedom is still not completely understood.
From a mathematical perspective, energy and
momentum in general relativity play a role
similar to electric charge in electromagnetism.
My approach consists first of all in developing
a better understanding in quantum electrodynamics
of the relation between improper
gauge degrees of freedom, boundary conditions
and electric charge at the mi- croscopic
level. On the one hand I have shown that, in
the presence of a static electric point-particle
source, the quantum state that corresponds
to the Coulomb solution is a co- herent state
of longitudinal and temporal photons. On the
other hand, I hope to be able touse old results
obtained in the context of the quantization of
monopôles, where boundary conditions have
been introduced as new dynamical gauge variables,
in order to under- stand and compute the
partition function for a non vanishing electric
potential. The last step would be to translate
121

Research on Gravitation, Strings and Cosmology
these results to the Chern-Simons formulation of
gravity in 2+1 dimensions, the gauge structure
of which is similar to the one of electromagnetism.
In this context, the role of the Coulomb
solution is played by the BTZ black hole.
Gravitational radiation and the BMS/CFT
correspondence
The problem of symmetries in asymptotically
flat 4 dimensional spacetimes at null infinity
goes back to the study of gravitational waves
in the early sixties. During the current academic
year, in collaboration with Cédric Toessaert,
we have been able to make arguably
significant progress in this context. What has
been largely overlooked so far is that, when
one follows the paradigm of two dimensional
quantum conformal field theories and focuses
on infinitesimal transformations without requiring
the associate finite transformations to be
globally well-defined, the so-called BMS algebra
naturally turns into an infinite-dimensional
extension of the Poincaré algebra. This extension
has both the Virasoro and the Poincaré
algebra as subalgebras and possesses a semidirect
structure similiar to that of the Poincaré
algebra itself.
Our result means for instance that there is no
longer a problem with angular momentum in
general relativity since the factor algebra of
bms4 modulo the abelian ideal of infinitesimal
supertranslations is now the infinite-dimensional
Virasoro algebra rather than the Lorentz algebra.
As another consequence, one gains almost
as much control on the physically relevant
problem of general relativity in 4 spacetime
dimensions as one has for the well studied case
of three dimensional asymptotically anti-de
Sitter gravity. In particular, we have started
by working out the details of how the bms4
algebra on solution space. We believe that our
understanding of the symmetry structure and its
action on solution space goes some way in getting
quantitative control on “structure X”, i.e., on
a holographic description of gravity with zero
cosmological constant.
122

Alice Bernamonti (VUB)
Third year PhD student of Professsor
Alexander Sevrin.
String Theory successfully provides a quantum
theory of gravity and is, at the same time, the
main candidate for the realization of force
unification.
Although String Theory cannot yet be tested
experimentally, it provides already important
results. For example, it offers a microscopic
insight in the quantum structure of black holes
and it realizes concretely the holographic
principle in the form of the gauge/gravity
duality, better known as the AdS/CFT correspondence.
Such a correspondence relates
different regimes of a gravity theory formulated
in an Anti de Sitter (AdS) space-time to the ones
of an ordinary conformal field theory in a fixed
background. It offers the possibility of studying
non-perturbative aspects of ordinary gauge field
theories and provides a description of the quantum
regime of String Theory, which is otherwise
lacking in a complete and independent form.
Cosmology is another area where String Theory
might be used to elucidate certain aspects
and in which it might even be confronted with
observations. In 2009, my work has addressed
mainly two lines of research: the study of cosmological
models in String Theory and of the thermalization
of strongly coupled plasmas through
holographic methods.
Holographic Cosmology
The present models for the first post Big Bang
moments, e.g. the well-known inflation theory,
do not answer many fundamental questions.
In the case of inflation, it is not clear how the initial
conditions allowing inflation arose. Inflationary
models also contain a singularity in the past,
making the theory incomplete. On the other
Research Interests of some Members
hand, inflationary models predict a spectrum
of the primordial density perturbations in agreement
with recent observations of the microwave
background radiation. Alternative models
predict a similar spectrum for a contracting universe
that might be connected to our expanding
universe through a cosmological singularity.
This observation leads to the question of whether
Big Crunch/Big Bang transitions are physically
feasible and whether the spectra remain
the same after such a transition. Clearly, these
questions cannot be answered in the context of
General Relativity, whose description becomes
invalid in the neighbourhood of singularities.
In the last few years several String Theory models
have been formulated to study this issue. It
has been shown that specific choices of boundary
conditions in an AdS space-time allow nonsingular
initial conditions to evolve into a Big
Crunch in a finite global time. To study this class
of cosmological singularities one can make use
of the gauge/gravity duality and turn to the dual
quantum field theory description, where, quite
generally, the singularity is manifested in the
presence of a potential unbounded from below
for a particular operator of the theory. Between
2007 and 2009, B. Craps, T. Hertog and
123
Research on Gravitation, Strings and Cosmology

Research on Gravitation, Strings and Cosmology
Figure 1 A virtual scalar particle is emitted by a
D3-brane and interacts an arbitrary number of times
with the AdS boundary before reabsorption. This
graph represents the leading contribution to the
unstable potential in the brane picture
infinite size in finite global time. Being domain
walls, every spherical brane that is nucleated
and stretched to infinity leaves behind a spacetime
with one less unit of flux, which is thus more
strongly curved than the original AdS. In a
gravity approximation of such a process, the
result is a Big Crunch singularity. The issue of
the possibility of a Big Crunch/Big Bang transition
translates in this language in specifying
what happens to these branes when they reach
the boundary of AdS in finite time and it
is still under study.
N. Turok have investigated the possibility of a
Big Crunch/Big Bang transition in such models.
Due to the difficulties encountered in keeping
the models under good computational control,
it is however not clear yet whether the transition
through the singularity occurs and how natural
is the prescription used to define evolution
beyond the singularity.
To get a better understanding of the system,
I have studied with B. Craps how the dynamics
described above can be rephrased in terms of
configurations of branes, extended objects that
appear in String Theory. The instability that is
produced by the boundary conditions, both in
the AdS bulk and in the dual field theory, manifests
itself into a negative unbounded potential
for spherical branes, which are domain walls
in AdS.
As a consequence, AdS can nucleate spherical
branes that are subsequently stretched to
This description seems likely to turn useful also
to model simpler systems that are closely related
to cosmological space-times. These are hairy
black hole solutions, which are dual to stable
multi-trace deformations of the boundary field
theory, and were studied by T. Hertog and G. T.
Horowitz. This class of solutions corresponds,
in the brane picture, to spherical branes that
nucleate in AdS and stabilize at a finite radius.
Strongly Coupled Plasmas
Another line of research I have been interested
in since June 2009 is the study of the thermalization
of strongly coupled plasmas through
holographic methods.
Heavy ion collisions at the Relativistic Heavy
Ion Collider (RHIC) are believed to produce
a deconfined, strongly coupled quark-gluon
plasma (QGP). In the initial stages of the collision,
when the QGP is produced, the system
is far from equilibrium; however, a near-ideal
124

hydrodynamic treatment becomes applicable
rather quickly after the collision event. The
understanding of the dynamics responsible for
such a rapid approach to local equilibrium is
not accessible through conventional tools, but
can be addressed in the framework of the AdS/
CFT correspondence. The duality has already
proved to be successful in describing the near
to equilibrium phase of the field theory, where a
thermal state in the boundary theory is dual to a
black hole metric in the bulk, suggesting it might
turn useful in describing also the approach to
thermal equilibrium of the system. The natural
dual description is thus in terms of gravitational
collapse in AdS leading to black hole formation.
Research Interests of some Members
I am now collaborating with colleagues from
VUB, as well as leading international experts in
the fields of String Theory and of QGP, and currently
exploring various directions in the investigation
of the thermalization dynamics. Phenomenologically,
the interesting setup to consider
is a five-dimensional bulk and boost invariant
configurations. This is because the central rapidity
region of a high-energy collision turns out
experimentally to be boost invariant to a good
approximation and because a four-dimensional
dual field theory is more likely to be related to
the real physics of QGP.
The final aim of these studies is extracting a lesson
on QGP and making contact with the
experimental physics performed at the
Brookhaven National Laboratory and at LHC.
Using the computational tools of the AdS/CFT
correspondence, however, we are restricted
for the moment to deal with highly simplified
theories, here N=4 SYM, and it is still hard to
find a direct link with QCD. Hopefully, however,
this line of research will allow reaching results
that are robust enough to be extended to real
world QGP.
Research on Gravitation, Strings and Cosmology
125

Research on Gravitation, Strings and Cosmology
Francesco Bigazzi (ULB)
Postdoctoral Member
String theory is a fascinating subject. Initially
inspired by the phenomenology of strong interactions,
this relativistic quantum theory of one
dimensional constituents has been proposed
as a candidate for a unifying picture of all the
fundamental interactions including quantum
gravity. Putting this proposal on solid grounds is
requiring incredible efforts and, at the same time,
is producing exciting theoretical discoveries and
revealing unexpected connections between
different branches of mathematics and physics.
One of the most remarkable achievements of
the theory, based on a fundamental duality
between open and closed strings, is a proposed
equivalence map between quantum gauge
theories and higher dimensional string models
on curved backgrounds. An astonishing corollary
is a weak/strong coupling duality relation
between these two classes of theories. Thus, in
particular, a suitably defined strong coupling regime
of a quantum field theory can be described
by the low energy, weak coupling limit of the
corresponding string model: a classical theory
of (super)gravity. The correspondence is holographic
as the field theory lives on the boundary
of the dual higher dimensional background.
This correspondence provides a relatively
simple computational framework to address non
perturbative field theory problems both at zero
and at finite temperature and densities. Differently
from other approaches, the gauge/gravity duality
is well suited to study not only equilibrium
physics but also real-time processes, phases with
non zero fermionic densities, transport coeffcients
and response to perturbations. Moreover it offers
clear geometrical pictures of otherwise inaccessible
dynamical processes at strong coupling.
Many relevant systems are described by strongly
coupled field theories. In the realm of particle
physics the prototypical example is quantum
chromodynamics (QCD) which, due
to asymptotic freedom, is strongly coupled at
low energies. Gravity alone is not enough to
provide a dual picture of QCD: for example
it cannot account for glueball and hadronic
resonances with arbitrary spins. Of course string
theory could, but a precise string model for
QCD is still missing. Despite this fact, the holo-
126

graphic approach has provided urprisingly new
perspectives into quantum chromodynamics,
for example into the properties of the strongly
coupled quark-gluon plasma discovered at the
Relativistic Heavy Ion Collider in Brookhaven
(USA).
My recent research works deal with the construction
of string theory duals to strongly
coupled non abelian gauge theories sharing
with QCD the crucial feature of being coupled
with dynamical matter fields which, like the
quarks, transform in the fundamental representation
of the gauge group. The aim has been
to study otherwise inaccessible aspects of
flavor physics. In lattice QCD, due to technical
constraints, the quarks are usually treated as
external, non-dynamical fields, neglecting their
vacuum polarization effects: it is the so-called
quenched approximation. In string theory, both
the quenched and the unquenched regimes can
be explored. My interest on the latter arises from
a series of reasons. Vacuum polarization effects
due to the quarks crucially affect the behavior
of QCD: for example they cause QCD to be a
screened theory (chromoelectric flux tubes can
break due to quark-antiquark pair creation)
instead than a purely confining one. Dynamical
flavors affect the phase diagram of the theory, its
low energy spectra, its transport properties and
interaction with external probes. Moreover, in
supersymmetric versions of QCD, they play a
crucial role in non perturbative dualities (like
the Seiberg duality) as well as in mechanisms of
dynamical supersymmetry breaking.
Research Interests of some Members
In 2009, in collaboration with researchers from
different European institutions (U.Barcelona, U.
Santiago de Compostela, Spain; U. Utrecht,
Netherlands; U. Swansea, UK; K.U. Leuven,
Belgium), we have provided novel supergravity
solutions dual to various classes of supersymmetric
unquenched QCD-like theories. The models
we have focused on have at least one characteristic
scale: this can either be a diagonal
mass term for the fundamental matter fields or
the temperature (in which case the dual gravity
solutions contain a black hole). In addition there
could be a dynamically generated infra-red
scale, much like in QCD.
A nice feature of the supergravity solutions we
have found is that they are regular when the
corresponding gauge theories are at low energy.
Regularity has enabled us to explore
the vacuum polarization effects due to the
fundamemtal matter fields on the infrared
gauge theory dynamics, for example on the
meson mass spectrum. Moreover, our analysis
has shown the occurrence of novel quantum
phase transitions in the static quark- antiquark
potential for gauge theories with two distinct
physical scales. The transitions are discontinuous
changes in the slope of the potential when
the ratio of the scales is below a certain critical
value. At the critical point the transition becomes
second order and above that it is perfectly
smooth. The critical exponents are universal for
gauge theories having a dual gravity description
and take the classical mean field values.
The black-hole solutions we have found are the
first examples of gravity duals to 3+1 dimensional
strongly coupled non abelian plasmas
interacting with dynamical fundamental matter
fields. These solutions allow a detailed analytical
study of the thermodynamical properties
as well as of the hydrodynamical regime of the
dual plasmas. Moreover they allow analyzing
their interactions with external probes, showing
how the flavors enhance the jet quenching at
strong coupling.
127
Research on Gravitation, Strings and Cosmology

Research on Gravitation, Strings and Cosmology
Alberto Mariotti (VUB)
Postdoctoral Member
In 2009, my work has mainly centered around
supersymmetry breaking, concerning both
String Theory engineering and phenomenological
properties. Here, I will discuss a project
focused on the study of semi-direct gauge
mediation, which combines both directions of
research. Other topics I addressed in the last
year are the dark matter realization in quiver
gauge theories and the electric-magnetic duality
in three dimensional N=2 Chern-Simons
matter theories.
Supersymmetry breaking and its mediation
to the MSSM
A main challenge in theoretical physics is the
quest for a unified description of all fundamental
forces. The Standard Model of fundamental
interactions provides a unified description of
strong and electroweak forces as quantum field
theories with gauge symmetries. On the other
hand, a unified description with Einstein General
Relativity is still lacking. Nowadays, the
main candidate for force unification is String
Theory. For this theory to be consistent, supersymmetry
(a new symmetry that maps bosons
into fermions and vice-versa) is required.
Besides String Theory, supersymmetry has
relevant phenomenological implications for
particle physics. In the minimal supersymmetric
version of the Standard Model (MSSM), for
every ordinary particle exists also a superpartner
with the same mass and quantum numbers
but with a spin differing by 1/2. The MSSM
(contrary to the non supersymmetric Standard
Model) shows a precise unification of the
coupling constants at high energy (GUT scale),
solves the hierarchy problem, and provides
a candidate for dark matter. In addition to
discovering the Brout-Englert-Higgs boson, discovering
physics beyond the Standard Model
is a major aim for the LHC at CERN, and the
MSSM is an important candidate for such new
physics.
However, if supersymmetry is realized in nature,
it must be broken, and masses for all unobserved
particles should be generated. The way
supersymmetry is broken gives distinct patterns
for the masses of the superpartners and for
their interactions with ordinary particles. These
patterns can be experimentally probed at the
weak scale, and also provide important information
about the physics at much higher scale.
The usual scenario for breaking supersymmetry
in the MSSM consists of a hidden sector where
supersymmetry is broken and a mediation
mechanism that transmits this breaking to the
visible sector. Roughly speaking, the mediation
mechanism generates in the MSSM Lagrangian
the supersymmetry breaking terms (the so
called soft terms).
A first possibility is that this mechanism is
gravitational, i.e. it is associated to general
relativity and to new physics that enters at the
Planck scale. In the simplest version of this
gravity mediated scenario, the hidden sector
and the visible sector are coupled through nonrenormalizable
operators (suppressed by the
Plank scale) in the effective Lagrangian. The
main difficulty with this scenario is that it involves
flavor changing neutral currents that are
typically generated when quantum corrections
to (super)gravity are taken into account. These
flavor-breaking contributions to the soft terms
are very dangerous, since the experimental
constraints on flavor changing neutral currents
are very stringent.
Another possibility is that the forces responsible
to the mediation of supersymmetry breaking
128

are the ordinary gauge interactions of the standard
model. In this gauge mediated scenario
there are typically messengers fields which
interacts with the supersymmetry breaking sector
and which are charged under the standard
model gauge groups. Loops of messengers
and gauge fields generates the soft terms in the
MSSM Lagrangian. Gauge mediation is one
of the most attractive possibility. First, gauge
interactions are flavor blind, hence there are
not additional flavor breaking contributions
with respect to the usual one in the standard
model (the yukawa couplings). Moreover this
mechanism is highly predictive for the large
amount of free parameters of the MSSM, and
has a natural dark matter candidate,
Research Interests of some Members
the gravitino, which is the
LSP (lightest supersymmetric
particle).
Semi Direct Gauge
Mediation
In the last year, in collaboration
with Riccardo Argurio,
Matteo Bertolini and Gabriele
Ferretti, we studied a
large subclass of gauge mediated
models, the so called
semi direct gauge mediation
(SDGM). In SDGM the visible
sector is connected to
some messenger fields via
the standard model gauge
interactions. The messenger
fields are also charged
under an additional gauge
group G_m which connects
them with the supersymmetry
breaking sector. This
scheme is reported in figure.
The central feature is that the
messengers communicates
with the supersymmetry
breaking sector only through the gauge interactions
G_m. The supersymmetry breaking is
communicated through loops of gauge fields of
G_m, messenger fields and gauge fields of the
standard model, hence generating masses for
the superpartners.
Observe that the messenger fields should also
have a tree level mass term, which should be
larger than the electroweak scale but also
smaller than the cut off scale (typically the GUT
scale), in order to give a sizeable contribution
to the sparticle masses. The natural origin of
this intermediate scale is an issue to be explained
in such semi direct gauge mediated
models.
129
Research on Gravitation, Strings and Cosmology

Research on Gravitation, Strings and Cosmology
SUSY breaking
sector
Messengers
SSM
sector
Non−SM gauge
interactions,
G m
In the first work on this subject, we investigated
the embedding of such models in String
Theory. The very symmetric structure of semi
direct gauge mediation, with messenger fields
in between two gauge groups linked to the
visible and the supersymmetry breaking sector
respectively, renders them particularly suitable
for an embedding in quiver gauge theories.
Quiver gauge theories arise in Type IIB string
theory as the world volume of D3 branes probing
Calabi Yau singularities. We have shown
how to embed the semi direct gauge mediation
scenario in different quiver gauge theories,
chiral and non chiral, describing the dynamics
of D3 branes. A very interesting feature of our
set up is that the messenger mass is dynamical
generated and hence naturally of the required
energy scale.
In the next project on SDGM, we instead concentrated
on the phenomenological signatures
specific of this class of models. We performed
a general analysis, which is independent on
the detailed structure of the supersymmetry
breaking sector. The only assumption we made
is that the mediation mechanism is SDGM, as
in figure. The supersymmetry breaking sector is
parametrized by the supercurrent that couples
to the gauge fields of G_m. The supersymmetry
breaking is encoded in the two point functions
of this supercurrent. We obtained the resulting
visible superpartner spectrum, by computing
quantum corrections at three and four loops.
We have found that the gaugino mass is exactly
vanishing at three loop level and that the
first non trivial contribution arises at five loops.
The sfermion masses arise at four loop level,
and we have found a closed formula for them.
The superpartner spectrum of SDGM, regardless
of the supersymmetry breaking sector, is
then characterized by suppressed gaugino
masses compared to sfermion masses. We then
proposed to combine SDGM with other mediation
mechanism, such as anomaly mediation, to
obtain a more balanced phenomenology.
130

Appraisals and Prizes
Marc Henneaux:
Glenn Barnich:
Ben Craps:
Research Interests of some Members
Theses defended in 2009
June 14, 2009: Daniel Persson, Arithmetic
and Hyperbolic Structures in String Theory,
Public PhD defense - Université libre de
Bruxelles, Belgium.
September : Nassiba Tatbi, Time is flying..........,
Public PhD defense - Université libre de
Bruxelles, Belgium.
Research on Gravitation, Strings and Cosmology
131

Research on Gravitation, Strings and Cosmology
January 7, 2009: Ben Craps, Cosmological
singularities and self-adjoint extensions, String
theory seminar - DESY, Hamburg, Germany.
January 8, 2009: Stanislav Kuperstein, A New
Holographic Model of Chiral Symmetry Breaking,
String Theory Group Seminar - LPTHE, Jussieu,
Paris, France.
January 21, 2009: Francesco Bigazzi, The Klebanov-Strassler
model with massive dynamical
quarks, High Energy Sector Seminars - SISSA,
Trieste, Italy.
January 22, 2009: Alberto Mariotti, Aspects
of supersymmetry breaking, IUAP meeting -
Université Catholique de Louvain, Louvain-la-
Neuve, Belgium.
January 25, 2009: Alexey Koshelev, Non-local
tachyon in cosmology, SIGRAV school on cosmology
- Galileo Galilei Institute, Firenze, Italy.
January 27, 2009: Thomas Hertog, Darwinism
in a Biophylic Universe, Public Lecture - de
Monty, Antwerp, Belgium.
January 28, 2009: Glenn Barnich, Dyons with
potentials/Asymptotic symmetries and central
extensions - Centro de Estudios Científicos,
Valdivia, Chile
.
February 10, 2009: Frank Ferrari, On the
microscopic formalism for N=1 super Yang-Mills
theories, Invited seminar - Bonn Universität,
Germany.
February 10, 2009: Daniel Persson, Partition
Functions for Three-Dimensional Gravity, CERN
Winter School on Supergravity, Strings and
Gauge Theories - CERN, Geneva, Switzerland.
February 10, 2009: Alexander Sevrin, Op zoek
naar het allerkleinste, Lecture for His Majesty
King Albert II of Belgium - Royal Palace Laeken,
Brussels, Belgium.
February 14, 2009: Thomas Hertog, Cosmology
from the top down, Seminar - New York
University, USA.
February 23, 2009: Marc Henneaux, Hidden
Symmetries of Gravity and Cosmology - Toyota
Technological Institute, Tokyo, Japan.
February 24, 2009: Marc Henneaux, International
Solvay Institutes: Past, Present and Future,
GRI Symposium II on Cluster Science - Nagoya,
Japan.
March 11, 2009: Marc Henneaux, Infinitedimensional
symmetries: the key to understanding
gravity? - Max-Planck Institut, Potsdam,
Germany.
March 18, 2009: Francesco Bigazzi, Massive
Dynamical Quarks and screening effects from
holography, String Theory seminar - Universidad
de Santiago de Compostela, Spain.
March 26, 2009: Amitabh Virmani, G2 Dualities
In 5d Minimal Supergravity, Theoretical Physics
Seminar - Universidad de Barcelona, Spain.
April 2, 2009: Amitabh Virmani, G2 Dualities
In 5d Minimal Supergravity, Theoretical Physics
Seminar - CENTRA, Instituto Superior Técnico,
Lisbon, Portugal.
April 8, 2009: Ben Craps, Holographic models
of cosmological singularities, “New perspectives
in string theory” Opening conference -
Galileo Galilei Institute, Firenze, Italy.
April 12, 2009: Alexey Koshelev, Bridging SFT
and Dark Energy, International conference on
SFT and related aspects - Steklov Mathematical
Institute, Moscow, Russia.
132

Invited Talks at Conferences, Seminars and Schools
April 12, 2009: Chethan Krishnan, Black holes
and CFTs, SISSA seminar - SISSA, Trieste, Italy.
April 14, 2009: Marc Henneaux, Conserved
Charges in Gravitational Theory: the Hamilonian
Approach - Erwin Schrödinger Internaional
Institute for Mathematical Physics, Vienna, Austria.
April 14, 2009: Thomas Hertog, Singularity
resolution in quantum cosmology, Gravity Workshop
- Texas A&M, College Station, USA.
April 14, 2009: Carlo Maccaferri, On the ghost
sector of OSFT, Second International Conference
on String Field Theory and Related Aspects
- Steklov Mathematical Institute, Moscow,
Russia.
April 22, 2009: Cyril Closset, The N=2 cascade
and branes at non-isolated singularities, Seminar
- Swansea University, United Kingdom.
April 23, 2009: Riccardo Argurio, Gauge/
Gravity Duality in Supersymmetric and Non-
Supersymmetric Vacua, International workshop
on supersymmetry and supersymmetry breaking
- Durham University, UK.
April 28, 2009: Alberto Mariotti, Two loop R
symmetry breaking, Invited talk - University of
California San Diego, USA.
April 30, 2009: Marc Henneaux, Algebraic
Methods in local field theory 1 and 2 - University
of Cracow, Poland.
May 18, 2009: Ella Jamsin, Hidden symmetries
as a black hole solution generating technique,
SU/Nordita High Energy and Gravity Seminar
- Stockholm University/Nordita institute, Stockholm,
Sweden.
May 22, 2009: Glenn Barnich, New aspects of
duality for electromagnetism, linearized gravity
and massless higher spin gauge fields, 4th
International Sakharov Conference - Lebedev
Physical Institute, Moscow, Russia.
May 27, 2009: Marc Henneaux, Algebraic
Methods in local field theory 1 and 2 - University
of Cracow, Poland.
May 27, 2009: Alexander Sevrin, Generalized
lagrangian and coisotropic branes, Group
seminar - ETH Zürich, Switzerland.
June 1, 2009: Alexey Koshelev, SFT as the
source for new cosmological models, Theory
Group Seminar - Ludwig-Maximilians-Universität,
Munich, Germany.
June 9, 2009: Alexander Sevrin, A la recherche
de l’infime, Talk at the invitation of Prince T. de
Merode and Bu!ld - Castle of Westerlo, Belgium.
June 10, 2009: Stanislav Kuperstein, Chiral
Symmetry Breaking with non-SUSY D7-branes in
ISD backgrounds, Theory Group High Energy
Seminar - Swansea University, UK.
June 15, 2009: Alexander Sevrin, A worldsheet
appoach for supersymmetric D-branes, Theory
Group Seminar - Imperial College, London, UK.
June 16, 2009: Thomas Hertog, Non-Gaussianity
in quantum cosmology, Workshop on Eternal
Inflation - ICTP, Trieste, Italy.
June 17, 2009: Daniel Persson, Arithmetic and
Hyperbolic Structures in String Theory, PhD thesis
presentation - Chalmers University of Technology,
Gothenburg, Sweden.
June 22, 2009: Laurent Houart, Aspects of N=2
D=4 supergravity I, Seminar - CECS, Valdivia, Chile.
Research on Gravitation, Strings and Cosmology
June 23, 2009: Laurent Houart, Aspects of N=2
D=4 supergravity II, Seminar - CECS, Valdivia, Chile.
133

Research on Gravitation, Strings and Cosmology
June 25, 2009: Axel Kleinschmidt, Symmetries
and Constraints, Strings 2009 - Rome, Italy.
June 29, 2009: Alexey Koshelev, Nonlocal
cosmological models: solutions and perturbations,
Invisible Universe 2009 - Paris,
France.
June 30, 2009: Glenn Barnich, Local BRST cohomology
of AKSZ-type sigma models - Scuola
Normale Superiore, Pisa, Italy.
June 30, 2009: Frank Ferrari, On localization
and some of its applications in supersymmetric
gauge theories: lecture I, Keynote lecture IST
String Fest - Instituto Superior Técnico, Lisbon,
Portugal.
July 1, 2009: Frank Ferrari, On localization
and some of its applications in supersymmetric
gauge theories: lecture II, Keynote lecture IST
String Fest - Instituto Superior Técnico, Lisbon,
Portugal.
July 6, 2009: Alexey Koshelev, SFT solutions in
cosmology, PASCOS 2009 - DESY, Hamburg,
Germany.
July 9, 2009: Alice Bernamonti, Multi-Trace Deformations
of AdS/CFT and Spherical D-branes,
Holographic cosmology conference - Perimeter
Institute, Waterloo, Canada.
July 13, 2009: Alexey Koshelev, Perturbation
analysis in non-local cosmological models, 12th
Marcel Grossman meeting - Paris, France.
July 15, 2009: Ben Craps, Holographic resolution
of cosmological singularities, Holographic
cosmology conference - Perimeter Institute,
Waterloo, Canada.
July 17, 2009: Thomas Hertog, Eternal inflation
in the no-boundary state, Workshop on Holographic
Cosmology - Perimeter Institute, Waterloo,
Canada.
July 22, 2009: Axel Kleinschmidt, Instanton corrections
to the universal hypermultiplet and the
Picard modular group, Quantum Theories and
Symmetries VI - University of Kentucky, Lexington,
USA.
August 1, 2009: Alexey Koshelev, Recent
progress with non-local cosmological models,
SQS’09 - JINR, Dubna, Russia.
August 17, 2009: Ben Craps, Holographic
models of cosmological singularities, Invited
talk - Ecole Normale Supérieure, Paris,
France.
August 19, 2009: Frank Ferrari, On the microscopic
approach to N=1 super Yang-Mills
theories, XXXIXème Institut d’été du Laboratoire
de Physique Théorique de l’École Normale Supérieure:
AdS, Théorie des champs conformes
et problèmes apparentées - École Normale
Supérieure, Paris, France.
August 20, 2009: Marc Henneaux, E11,
Borcherds Algebras and Maximal Supergravity,
33rd Johns Hopkins Workshop “Maximal
Supersymmetry” - Göteborg, Sweden.
August 20, 2009: Axel Kleinschmidt, Supersymmetric
Quantum Cosmological Billards, 33rd
Johns Hopkins Workshop “Maximal Supersymmetry”
- Chalmers Technical University, Gothenburg,
Sweden.
August 21, 2009: Alexey Koshelev, Stable
modified DGP brane-world models, Internatinal
Bogolyubov conference 2009 - JINR, Dubna,
Russia.
August 28, 2009: Alberto Mariotti, Semi-direct
gauge mediation and D-branes at singularities,
134

Invited Talks at Conferences, Seminars and Schools
Invited talk - Chalmers University, Gotheborg,
Sweden.
September 3, 2009: Thomas Hertog, Inhomogeneities
in the no-boundary state, Challenges
in Theoretical Cosmology - Tufts University, Talloires,
France.
September 7, 2009: Alexey Koshelev, SFT nonlocality
in cosmology: solutions, perturbations
and observational evidences, COSMO’09 -
CERN, Geneva, Switzerland.
September 7, 2009: Wieland Staessens, Susy
and the brane: a sigma-model story, 15-th European
Workshop on String Theory - ETH Zürich,
Switzerland.
September 8, 2009: Frederik De Roo, p-branes
on the waves, 15-th European Workshop on
String Theory - ETH Zürich, Switzerland.
September 8, 2009: Francois Dehouck, Gravitational
Duality: a NUT story, 15th European
Workshop on String Theory - ETH Zürich, Switzerland.
September 11, 2009: Francesco Bigazzi, Gravity
Duals of Unquenched Quark-Gluon Plasmas,
15th European Workshop on String Theory -
Zurich, Switzerland.
September 11, 2009: Thomas Hertog, The
no-boundary measure in the regime of eternal
inflation, Seminar - CERN, Geneva, Switzerland.
September 14, 2009: Ben Craps, Holographic
resolution of cosmological singularities, High energy
theory seminar - University of Pennsylvania,
Philadelphia, USA.
September 16, 2009: Ben Craps, Holographic
resolution of cosmological singularities, Informal
seminar - Princeton University, USA.
September 19, 2009: Glenn Barnich, Asymptotically
flat spacetimes revisited, 2nd School and
Workshop on Quantum Gravity and Quantum
Geometry - Corfu Summer Institute, Greece.
September 22, 2009: Stanislav Kuperstein,
ABJ(M) and Fractional M2’s with Fractional
M2 Charge, A new year of string theory -
Tel-Aviv University, Israel.
October 23, 2009: Daniel Persson, Automorphic
Forms and Instanton Effects in String Theory,
MP2 Workshop on Physics and
Developments in Modern Algebra - Chalmers
University of Technology, Gothenburg, Sweden.
October 29, 2009: Marc Henneaux, Infinitedimensional
symmetries: the key to understanding
gravity? - Jagiellonian University, Cracow,
Poland.
November 5, 2009: Alexander Sevrin, Supersymmetric
D-branes from a worldsheet point of
view, Theoretical High Energy Seminar - Niels
Bohr Institute, Copenhagen, Denmark.
November 18, 2009: Francesco Bigazzi, D3-
D7 Quark-Gluon Plasmas, String Theory seminar
- Universiteit Utrecht, the Netherlands.
November 18, 2009: Ben Craps, Een hologram
van de oerknal? Snaartheoriemodellen voor
het zeer vroege heelal, Lecture as the recipient
of the 2009 Frans Van Cauwelaert prize -
Koninklijke Vlaamse Academie van België
voor Wetenschappen en Kunsten, Brussels,
Belgium.
November 23, 2009: Marc Henneaux, Comments
on Horava-Lifshitz gravity - Institute of
Physics, Cracow, Poland.
December 1, 2009: Ben Craps, The cosmological
singularity problem, The nineteenth work-
135
Research on Gravitation, Strings and Cosmology

Research on Gravitation, Strings and Cosmology
shop on general relativity and gravitation in
Japan - Rikkyo University, Tokyo, Japan.
December 7, 2009: Marc Henneaux, Lorentzian
Kac-Moody algebras, Borcherds superalgebras
and maximal supergravity - Institute of
Mathematics, Cracow, Poland.
December 8, 2009: Carlo Maccaferri, The
ghost sector of OSFT: Analysis and Applications,
APCTP Focus Program on Current Trends
in String Field Theory - APCTP Headquarters,
Pohang, South Korea.
December 10, 2009: Marc Henneaux, Asymptotic
behaviour of gravity in three dimensions -
Jagiellonian University, Cracow, Poland.
December 15, 2009: Francois Dehouck, Gravitational
Duality: a NUT story, Seminars - Centro
de Estudios Cientificos, Valdivia, Chile.
December 21, 2009: Alberto Mariotti, Supersymmetry
breaking, Avogadro meeting - SISSA,
Trieste, Italy.
136

1. Antonio Amariti, Luciano Girardello, Alberto
Mariotti, “Stringy instantons from Seiberg duality”
- Published in Nucl.Phys.Proc.Suppl. 192-
193:161-162,2009.
2. A. Amariti, L. Girardello, A. Mariotti, “Stringy
instantons from Seiberg duality” - Published in
Fortsch.Phys.57:478-484,2009.
3. Antonio Amariti, Alberto Mariotti, “Two Loop
R-Symmetry Breaking” - Published in JHEP
0907:071,2009 e-Print: arXiv:0812.3633
[hep-th].
4. R. Argurio, M. Bertolini, G. Ferretti and A. Mariotti,
“Natural semi- direct gauge mediation
and D-branes at singularities” - Phys. Rev. D
80
(2009) 045001 [arXiv:0906.0727 [hep-th]].
Publications 2009
10. F. Benini, M. Bertolini, C. Closset and S.
Cremonesi, “The N=2 cascade revisited and the
enhancon bearings” - Phys. Rev. D 79 (2009)
066012 [arXiv:0811.2207 [hep-th]].
11. E. A. Bergshoeff, O. Hohm, A. Kleinschmidt,
H. Nicolai, T. A. Nutma and J. Palmkvist, “E10
and Gauged Maximal Supergravity” - JHEP
0901 (2009) 020 [arXiv:0810.5767 [hep-th]].
12. E. A. Bergshoeff, M. de Roo, S. F. Kerstan,
A. Kleinschmidt and F. Riccioni, “Dual Gravity
and Matter” - Gen. Rel. Grav. 41 (2009) 39
[arXiv:0803.1963 [hep-th]].
13. Alice Bernamonti, Ben Craps, “D-Brane Potentials
from Multi-Trace Deformations in AdS/
CFT” - Published in JHEP 0908:112,2009
e-Print: arXiv:0907.0889 [hep-th].
Research on Gravitation, Strings and Cosmology
5. R. Argurio, F. Dehouck and L. Houart, “Boosting
Taub-NUT to a BPS NUT-wave” - JHEP
0901 (2009) 045 [arXiv:0811.0538 [hep-th]].
6. R. Argurio, F. Dehouck and L. Houart, “Supersymmetry
and Gravita- tional Duality” - Phys.
Rev. D 79 (2009) 125001 [arXiv:0810.4999
[hep- th]].
7. C. Bachas, C. Bunster and M. Henneaux,
“Dynamics of Charged Events” - Phys. Rev.
Lett. 103 (2009) 091602 [arXiv:0906.4048
[hep-th]].
8. G. Barnich and C. Troessaert, “Duality and
integrability: Elec-tromagnetism, linearized
gravity and massless higher spin gauge fields
as bi-Hamiltonian systems” - J. Math. Phys. 50
(2009) 042301 [arXiv:0812.4668 [hep-th]].
14. F. Bigazzi, A. L. Cotrone, A. Paredes and A.
V. Ramallo, “Screening effects on meson masses
from holography” - JHEP 0905 (2009) 034
[arXiv:0903.4747 [hep-th]].
15. F. Bigazzi, A. L. Cotrone, A. Paredes and A.
V. Ramallo, “The Klebanov-Strassler model with
massive dynamical flavors” - JHEP 0903
(2009) 153 [arXiv:0812.3399 [hep-th]].
16. F. Bigazzi, A. L. Cotrone, A. Paredes and A.
Ramallo, “Non chiral dy- namical flavors and
screening on the conifold” - Fortsch. Phys. 57
(2009) 514 [arXiv:0810.5220 [hep-th]].
17. F. Bigazzi, A. L. Cotrone and A. Paredes,
“Phase transitions in large N(c) heavy quark potentials”
- Nucl. Phys. Proc. Suppl. 192-193
(2009) 134 [arXiv:0810.4018 [hep-th]].
9. G. Barnich and C. Troessaert, “Manifest spin
2 duality with electric and magnetic sources” -
JHEP 0901 (2009) 030 [arXiv:0812.0552
[hep-th]].
18. F. Bigazzi, A. L. Cotrone, J. Mas, A. Paredes,
A. V. Ramallo and J. Tarrio, “D3-D7 Quark-
Gluon Plasmas” - JHEP 0911 (2009) 117
[arXiv:0909.2865 [hep-th].]
137

Research on Gravitation, Strings and Cosmology
19. P. Binetruy, A. Bohe, T. Hertog and D. A.
Steer, “Gravitational Wave Bursts from Cosmic
Superstrings with Y-junctions” - Phys. Rev. D
80, 123510 (2009) [arXiv:0907.4522
[hep-th]].
20. L. Bonora, C. Maccaferri, R. J. Scherer
Santos and D. D. Tolla, “Ghost story. II. The midpoint
ghost vertex” - JHEP 0911 (2009) 075
arXiv:0908.0055 [hep-th].
21. L. Bonora, C. Maccaferri and D. D. Tolla,
“Ghost story. III. Back to ghost number zero” -
JHEP 0911 (2009) 086 arXiv:0908.0056
[hep-th].
22. L. Brink, S. S. Kim and P. Ramond, “E7
(7) on the Light Cone” - AIP Conf. Proc. 1078
(2009) 447 [JHEP 0806 (2008) 034]
[arXiv:0801.2993 [hep-th]].
23. G. Compère, S. de Buyl, E. Jamsin and A.
Virmani, “G2 Dualities in D=5 Supergravity
and Black Strings” - Class. Quant. Grav. 26
(2009) 125016 [arXiv:0903.1645 [hep-th]].
24. Ben Craps, Frederik De Roo, Oleg Evnin,
Federico Galli, “p-branes on the waves” - Published
in JHEP 0907:058,2009 e-Print:
arXiv:0905.1843 [hep-th].
25. Ben Craps, Thomas Hertog, Neil Turok,
“A Multitrace deformation of ABJM theory” -
Published in Phys.Rev.D80:086007,2009
e-Print: arXiv:0905.0709 [hep-th].
26. Ben Craps, Frederik De Roo, Oleg Evnin,
“Free string evolution across plane wave singularities”
- Published in Fortsch.Phys.57: 666-
671,2009 e-Print: rXiv:0901.1989 [hep-th].
27. Ben Craps, Frederik De Roo, Oleg Evnin,
“Can free strings propagate across plane
wave singularities?” - Published in JHEP
0903:105,2009 e-Print: arXiv:0812.2900
[hep-th].
28. Anatoly Dymarsky, Stanislav Kuperstein, Jacob
Sonnenschein, “Chiral Symmetry Breaking
with non-SUSY D7-branes in ISD backgrounds”
- Published in JHEP 0908:005,2009 e-Print:
arXiv:0904.0988 [hep-th].
29. F. Englert and L. Houart, “The emergence
of fermions and the E11content” in “Quantum
Mechanics of Fundamental Systems: The Quest
for Beauty and Simplicity”, M. Henneaux and J.
Zanelli eds., pp. 125-146, Springer (New
York: 2009), arXiv:0806.4780 [hep-th].
30. Jarah Evslin, Stanislav Kuperstein, “ABJ(M)
and Fractional M2’s with Fractional M2
Charge” - Published in JHEP 0912:016,2009
e-Print: arXiv:0906.2703 [hep-th].
31. Jarah Evslin, Stanislav Kuperstein, “Which
BPS Baryons Minimize Volume?” - Published
in Phys.Rev.D79:046007,2009 e-Print:
arXiv:0809.4594 [hep-th].
32. A. J. Feingold, A. Kleinschmidt and H.
Nicolai, “Hyperbolic Weyl groups and the four
normed division algebras” - J.Algebra 322
(2009) 1295-1339 [arXiv:0805.3018 [math.RT]].
33. F. Ferrari and V. Wens, “Flavors in the
microscopic approach to N=1 gauge theories”
- JHEP 0905 (2009) 124 [arXiv:0904.0559
[hep-th]].
34. F. Ferrari, “Galois symmetries in Super
Yang-Mills Theories” - JHEP 0903 (2009) 128
[arXiv:0901.4079 [hep-th]].
35. F. Ferrari, “On the Geometry of Super
Yang-Mills Theories: Phases and Irreducible
Polynomials” - JHEP 0901 (2009) 026
[arXiv:0810.0816 [hep-th]].
138

36. J. Hartle and T. Hertog, “Replication Regulates
Volume Weighting in Quantum Cosmology”
- Phys. Rev. D 80, 063531 (2009)
[arXiv:0905.3877 [hep-th]].
37. M. Henneaux, E. Jamsin, A. Kleinschmidt
and D. Persson, “Mas- sive Type IIA Supergravity
and E10” - Fortsch. Phys. 57 (2009) 580
[arXiv:0901.4848 [hep-th]].
38. M. Henneaux, C. Martinez and R. Troncoso,
“Asymptotically anti-de Sitter spacetimes in topologically
massive gravity” - Phys. Rev. D 79
(2009) 081502 [arXiv:0901.2874 [hep-th]].
39. M. Henneaux, E. Jamsin, A. Kleinschmidt
and D. Persson, “On the E10/Massive Type IIA
Supergravity Correspondence” - Phys. Rev. D
79 (2009) 045008 [arXiv:0811.4358 [hepth]].
40. M. Henneaux, “Kac-Moody algebras and
the structure of cosmological singularities: a
new light on the Belinskii-Khalatnikov-Lifshitz
analysis,” in “Quantum Mechanics of Fundamental
Systems: The Quest for Beauty and
Simplicity”, M. Henneaux and J. Zanelli eds.,
pp. 155-166, Springer (New York: 2009),
arXiv:0806.4670 [hep-th].
Publications 2009
44. A. Kleinschmidt, M. Koehn and H. Nicolai,
“Supersymmetric quantum cosmological
billiards” - Phys. Rev. D 80 (2009) 061701
[arXiv:0907.3048 [gr-qc]].
45. A. Koshelev, “Tachyon condensation as
a cosmological model” - Published in Fortsch.
Phys.57:618-624,2009.
46. C. Krishnan and S. Kuperstein, “A Comment
on Kerr-CFT and Wald Entropy” - Phys. Lett. B
677 (2009) 326 [arXiv:0903.2169 [hep-th]].
47. C. Krishnan, C. Maccaferri and H. Singh,
“M2-brane Flows and the Chern-Simons Level”
- JHEP 0905 (2009) 114 [arXiv:0902.0290
[hep- th]].
48. C. Krishnan and C. Maccaferri, “Membranes,
Strings and Integrability” -Fortsch.
Phys. 57 (2009) 632 [arXiv:0810.3825
[hep-th]].
49. Alexander Sevrin, Wieland Staessens,
Alexander Wijns, “An N=2 worldsheet approach
to D-branes in bihermitian geometries:
II. The General case” - Published in JHEP
0909:105,2009 e-Print: arXiv:0908.2756
[hep-th].
Research on Gravitation, Strings and Cosmology
41. L. Houart, A. Kleinschmidt, J. Lindman
Hornlund, D. Persson and N. Tabti, “Finite and
infinite-dimensional symmetries of pure N=2 supergravity
in D=4” - JHEP 0908 (2009) 098
[arXiv:0905.4651 [hep-th]].
42. E. Imeroni and A. Sinha, “Non-relativistic
metrics with extremal limits” -JHEP 0909
(2009) 096 [arXiv:0907.1892 [hep-th]].
43. S. S. Kim, T. Kim and Y. Kim, “Surplus Solid
Angle: Toward As- trophysical Test of Horava-
Lifshitz Gravity” - Phys. Rev. D 80 (2009)
124002 [arXiv:0907.3093 [hep-th]].
50. Alexander Sevrin, Wieland Staessens,
Alexander Wijns, “N=2 world-sheet approach
to D-branes on generalized Kahler
geometries. II. Dualities” - Published in
Fortsch.Phys.57:691-697,2009 e-Print:
arXiv:0901.4250 [hep-th].
51. Alexander Sevrin, Wieland Staessens,
Alexander Wijns, “N = 2 world-sheet approach
to D-branes on generalized Kaehler
geometries. I. General formalism” - Published
in Fortsch.Phys.57:684-690,2009 e-Print:
arXiv:0810.5355 [hep-th].
139

Research on Gravitation, Strings and Cosmology
Preprints
52. Antonio Amariti, Luciano Girardello,
Alberto Mariotti, “Pseudomoduli Dark Matter
and Quiver Gauge Theories” - e-Print: arXiv:
0910.3615 [hep-th].
53. Antonio Amariti, Davide Forcella,
Luciano Girardello, Alberto Mariotti, “3D
Seiberg-like Dualities and M2 Branes” - e-Print:
arXiv:0903.3222 [hep-th].
54. R. Argurio and F. Dehouck, “Why not a
di-NUT? or Gravitational du- ality and rotating
solutions” - arXiv:0909.0542 [hep-th].
55. Riccardo Argurio, Matteo Bertolini,
Gabriele Ferretti, Alberto Mariotti, “Patterns of
Soft Masses from General Semi-Direct Gauge
Mediation” - e-Print: arXiv:0912.0743 [hep-ph].
56. L. Bao, A. Kleinschmidt, B. E. W. Nilsson, D.
Persson and B. Pioline, “Instanton Corrections to
the Universal Hypermultiplet and Automor- phic
Forms on SU(2,1)” - arXiv:0909.4299 [hep-th].
57. G. Barnich and C. Troessaert, “Symmetries
of asymptotically flat 4 dimensional spacetimes
at null infinity revisited” - arXiv:0909.2617 [grqc].
58. G. Barnich and M. Grigoriev, “A Poincare
lemma for sigma models of AKSZ type”-
arXiv:0905.0547 [math-ph].
59. F. Benini, C. Closset and S. Cremonesi,
“Chiral flavors and M2-branes
at toric CY4 singularities” - arXiv:0911.4127
[hep-th].
60. F. Bigazzi, A. L. Cotrone and J. Tarrio,
“Hydrodynamics of fundamental matter” -
arXiv:0912.3256 [hep-th]].
61. C. Closset, “Toric geometry and local
Calabi-Yau varieties: An intro- duction to toric
geometry (for physicists)” - arXiv:0901.3695
[hep-th].
62. T. Damour, A. Kleinschmidt and H. Nicolai,
“Sugawara-type constraints in hyperbolic coset
models” - arXiv:0912.3491 [hep-th].
63. M. Henneaux, A. Kleinschmidt and G. L.
Gomez, “A dynamical incon- sistency of Horava
gravity” - arXiv:0912.0399 [hep-th].
64. L. Houart, A. Kleinschmidt and J. L. Hornlund,
“Some Algebraic As- pects of Half-BPS
Bound States in M-Theory” - arXiv:0911.5141
[hep-th].
65. A. Kleinschmidt and H. Nicolai, “Cosmological
quantum billiards” - arXiv:0912.0854
[gr-qc].
66. Alexey S. Koshelev, “SFT non-locality in
cosmology: solutions, perturbations and observational
evidences” - e-Print: arXiv:0912.5457
[hep-th].
67. Alexey S. Koshelev, Sergey Yu. Vernov,
“Cosmological perturbations in SFT inspired
non-local scalar field models” - e-Print:
arXiv:0903.5176 [hep-th].
68. C. Krishnan, “Tomograms of Spinning Black
Holes” - arXiv:0911.0597 [hep-th].
69. B. Pioline and D. Persson, “The automorphic
NS5-brane” - arXiv:0902.3274 [hep-th].
70. N. Tabti, “Kac-Moody algebraic structures
in supergravity theories” - arXiv:0910.1444
[hep-th].
140

TROUVER IMAGE ??
Publications 2009
Research on Gravitation, Strings and Cosmology
141

142

Invited Talks at Conferences, Seminars and Schools
Research carried out
in the group of
the Deputy
Director
Research carried out in the Group of the Deputy Director
143

Research carried out in the group
of the Deputy Director
Members
J. Bijtebier
F. Lambert (head of the group)
M. Musette
Z. Suchanecki
A. Volkov
Postdoctoral Members
T. Durt
(TONA-VUB)
I. Loris
(VUB)
C. Verhoeven
(BIRA-VUB)
R. Willox
(University of Tokyo)
Visitors
o
o
6 December 2009: Professor Ludwig
Faddeev (Steklov Mathematical Institute,
St Petersburg, Russia and member of the
Scientific Committee for Physics of the
International Solvay Institutes).
5-12 December 2009: Professor Robert
Conte (CEA and ENS-Cachan, France) –
11 December 2009: Seminar “All the
elliptic solutions of a given algebraic
nonlinear ordinary differential equation”.
Research Summary
Solitons, integrable systems and beyond
As indicated in previous reports, the study of
particle like excitations (solitons) which appear
as explicit solutions to a remarkable collection
of classical nonlinear wave equations (soliton
equations) has been a long term endeavour of a
VUB-group associated with the Solvay Institutes,
and represented by three senior members (M.
Musette, F. Lambert and R. Willox (*)).
From the physical point of view, solitons play an
important role in a variety of areas (nonlinear
optics, plasmaphysics, condensed matter physics
and particle physics). From the mathematical
point of view, the soliton equations are related
to a well-known chapter of mechanics: the
theory of integrable systems. However, solitons
are non- perturbative solutions of nonlinear
equations which must be viewed as integrable
dynamical systems with infinitely many degrees
of freedom. These systems can be continuous
(represented by nonlinear partial differential
equations), discrete (nonlinear lattices) or even
“ultra discrete” (cellular automata). Discrete
integrable systems (DIS) are believed to be
more fundamental than their continuous, or
semi-continuous, counterparts, for the continuous
systems can be obtained from the DIS (and
not the other way round). The study of DIS, and
of their applicability, has therefore become a
major research activity.
The group’s research in this domain is conducted
in collaboration with members of the
University of Glasgow, the Université de Paris
(Diderot-Paris-7), the Ecole Polytechnique of
Paris, the University of Tokyo, Rikkyo University
and Aoyama Gakuin University (Japan).
(*) R. Willox is a member of the International Solvay Institutes
for Physics and Chemistry, who is since several years active in
Japan, as a Professor at the University of Tokyo.
144

The activities in 2009 can be summarized as
follows:
o Investigations into the systematic construction
of DIS and into their relationship with Yang-Baxter
maps (set-theoretical solutions of the Yang-
Baxter equation) which, in the ultra-discrete limit,
give rise to integrable cellular automata. Study
of the symmetries of such a Yang-Baxter maps,
and of their relation to geometric crystals associated
with various affine Lie algebras (collaboration
with University of Glasgow and Rikkyo
University).
o Study of different discretizations of 1+1
dimensional integrable systems, with the aim of
clarifying their relationships (e.g. in the form of
discrete Miura transformations); a collaboration
with Université Paris 7 and Ecole Polytechnique.
o Development of discretization techniques for
a systematic construction of cellular automaton
models with applications in population dynamics,
epidemiology and ecology (collaboration
with Université Paris-7 and Ecole Polytechnique).
o Analysis of the initial value problem for the ultradiscrete
KdV equation, defined over integers.
This remarkable cellular automaton exhibits
multi-soliton interactions of KdV-type (collaboration
with Université Paris-7, Ecole Polytechnique
and Aoyama Gakuin University).
Members and Research Summary
The study of elementary solutions of integrable
NLPDE’s, and of corresponding ordinary differential
equations has awakaned our interest
in “nonlinear special functions”. Among these,
the elliptic function is the most elementary. By
combining two classical theorems of Briot and
Bouquet with an algorithm of Poincaré we built
a novel algorithm which produces closed forms
expressions for the elliptic or degenerate elliptic
(i.e. rational in one exponential, or rational)
solutions of any given algebraic ordinary differential
equation. Physically, these solutions are related
to s.c. “cnoïdal waves, fronts and pulses…)
Regularization of ill-posed inverse problems
Inverse problems deal with the reconstruction,
from measured effects, of the “source” which
causes these effects (e.g. reconstruction in scattering
theory of the potential from scattering
data). Physically, the interest of solving such a
problem can be pretty obvious (a historical example
is the determination of Newton’s force of
gravity from the shape of the planetary orbits).
In practice however, inverse problems are, as
such, almost intractable as a result of their illposed
character. They require an appropriate
regularization.
The research carried out in this context in 2009
is a continuation of Dr I. Loris’s activity in 2008,
which aimed at developing efficient regularization
tools. A recent method of regularization
consists of imposing a sparsity-promoting
penalty on a least squares functional (such a
penalty consists of the 1-norm of the model
coefficients in particular basis). Under the right
conditions, such a penalty strategy may yield
better reconstructions than those obtained with
the traditional 2-norm penalization. A drawback
of the method is that the algorithms used for the
minimization of the least squares functional with
a 1-norm penalty term are less efficient than the
traditional ones.
This problem has been addressed: the method
was improved by means of a novel algorithm,
obtained in collaboration with applied mathematics
teams of the ULB and the University of
Genoa and Modena-Regio Emilia.
The regularization techniques have been implemented
for use in seismic tomography reconstructions
(collaboration with applied mathematics
and geo-science departments of Princeton
145
Research carried out in the Group of the Deputy Director

Research carried out in the group
of the Deputy Director
University and University of Nice). The effectiveness
of sparsity-promoting penalties was tested
in the case of severely ill-conditioned and noisy
problems (measurement data are often incomplete
and contaminated with noise).
Application of our regularization method to
finance was considered in connection with Markowitz
portfolio theory (collaboration with ULB
and University of Princeton). The wide applicability
of sparsity-promoting techniques motivated
the organization of a Solvay Workshop, in
collaboration with Professor Ingrid Daubechies
from Princeton University. This Workshop on
“Sparsity, Learning and Computation” took
place in Brussels from 12 to 14 February 2009.
Invited speakers included John Lafferty (Carnegie
Mellon University), Robert Novak (University
of Wisconsin, Madison) and Stephen Smale
(University of California, Berkeley).
Fundamental aspects of time and information
in quantum theory
Elaborating further on the time operator and
(super)time operator proposed by Professor
Prigogine and co-workers, we showed that fundamental
aspects of time in quantum theory can
be brought to the realm of experimental physics.
In addition to the experiments which can be realized
with kaons or B and D mesons, we conceived
crucial experiments that may be realized
with entangled pairs of mesons prepared in Bell
states (collaboration with Université Paris7).
We continued our investigations in quantum
information theory, which are carried out in the
framework of a Brussels Impulse Program (the
Cryptase project). The idea is to encode a secret
and confidential cryptographic key into metastable
nuclei. We studied the statistical properties
of a Quantum Random Generator based
on quantum stochastic processes, which was
developed at the ULB (Cryptase and SeQur
projects).
Our research regarding the application of
Galois theory to quantum information science
has been concluded with the preparation of a
comprehensive review paper (collaboration
with the National University of Singapore).
146

Invited Talks at Conferences, Seminars and Schools
3 April 2009: R. Willox, Geometric Aspects of Discrete and Ultra-Discrete Integrable Systems, University
of Glasgow, Scotland, UK
April, 2009: T. Durt, Wigner tomography of two qubit states and quantum cryptography, Belgian
Physical Society Annual Congress, Hasselt.
29 May 2009: I. Loris, Algorithms and Penalizing Strategies, at the Workshop on Tomography with
Wavelets, Institut Océanologique, Villefranche-sur-mer, France.
11 June 2009: I. Loris, Sparse and stable Markowitz portfolios, at the First European Conference of
the Society for Financial Econometrics, Geneva, Switzerland.
22 July 2009: I. Loris, On the convergence rate of iterative L1-minimization algorithms, at a Conference
on Applied Inverse Problems, Vienna, Austria.
24 July 2009: I. Loris, Novel regularization techniques for seismic tomography, Conference on Applied
Inverse Problems, Vienna, Austria.
15 November 2009: T. Durt, Applications of Galois fields in quantum information theory, Expository
Quantum Lectures, Series 3, EQuaLS 3, Putra Jaja, Kuala Lumpur, Malaysia.
Research carried out in the Group of the Deputy Director
8 December 2009: T. Durt, Quantum Coherence in Biology : Myth or Reality ? Internal Seminar,
Griffith University, Brisbane, Australia.
147

Research carried out in the group
of the Deputy Director
Publications
J. Brodie, I. Daubechies, C. De Mol, D. Giannone
and I. Loris, “Sparse and stable Markowitz
portfolios” – Proc. Nat. Acad. of Sciences of the
USA 106 (2009), 122671 2272.
R. Conte and M. Musette, “Elliptic general
analytic solutions” – Stud. In Appl. Math. 123
(2009), 63-81.
J. Corbett and T. Durt, “Collimation processes in
quantum mechanics interpreted in quantum real
numbers” – Stud. Hist. and Phil. of Mod. Phys.
40 (2009), 68.
S. Kakei, J.J.C. Nimmo and R. Willox, “Yang-
Baxter maps and the discrete KP hierarchy” –
Glasgow Math. Journ. 51A (2009), 107-119.
S. Kakei, J.J.C. Nimmo and R. Willox, “Yang-
Baxter maps and the discrete KP hierarchy” –
RIMS Kokyuroku 1650 (2009), 162-172.
I. Loris, M. Bertero, C. De Mol, R. Zanella and
L. Zanni, “Accelerating gradient projection
methods for L1-constrained signal recovery by
steplength selection rules” – Appl. and Comp.
Harmonic Anal. 27 (2009), 247254.
I. Loris, “On the performance of algorithms for
minimization of L1-penalized functionals” – Inverse
Probl. 25 (2009), 035008.
I. Loris, H. Douma, G. Nolet, I. Daubechies
and C. Regone, “Nonlinear regularization
techniques for seismic tomography” – Journ. of
Comp. phys. 229 (2009), 890905.
A. Ramani, B Grammaticos and R. Willox, “Contiguity
relations for discrete and ultra-discrete
Painlevé equations” – Journ. Nonl. Math. Phys.
15 (2009), 353-364.
A. Ramani, B. Grammaticos, J. Satsuma and R.
Willox, “On two (not so) new integrable partial
differential equations” – Journ. Phys. A, Math.
Theor. 42 (2009) 282002 (6pp).
R. Willox, A. Ramani and B. Grammaticos, “A
discrete-time model for cryptic oscillations in
predator-prey systems” – Physics D 238 (2009),
2238-2245.
R. Willox, “Integrable systems and equations:
soliton and Painlevé equations” – Mathematical
Sciences 557 (2009), 12-17.
148

Preprints
J.C. Corbett and T. Durt, “An intuitionistic model
of electron single interference” – Studia Logica,
accepted for publication.
M. Courbage, T. Durt and M. Saberi, “Dissipative
dynamics of the Kaon decay process” – Comm.
in Nonl. Sciences and Num. Comp., accepted
for publication.
M. Courbage, T. Durt and S.M. Saberi Fathi,
“A wave-function model for CP-violation in mesons”
– arxiv: quant-ph/0903.4143v1 (2009).
F. Daerden, J.A. Whiteway, R. Davy, C. Verhoeven,
L. Komguen, C. Dickinson, P.A. Taylor and N.
Larsen, “Simulating observed boundary layer
clouds on Mars” – Geophys. Res. Lett., accepted
for publication.
T. Durt, “Anthropomorphic quantum Darwinism
as an explanation for classicality” – Foundat. of
Science, accepted for publications, http://arxiv.
org/abs/0912.5508.
Publications & Preprints
T. Durt, “Experimental proposal for testing the
emergence of environment induced classical
selection rules in biological systems” – Studio
Logica, accepted for publication.
T. Durt and A. Hermanne, “Cryptographic
encryption scheme for solving the trusted courier
problem based on metastable excited nuclei” –
quant-ph/09103131 (2009).
S. Kakei, J.J.C. Nimmo and R. Willox, “Yang-
Baxter maps from the discrete BKP equation” –
submitted to SIGMA (2009) http://arxiv. org/
abs/0911.2684.
F. Lambert, “Internationalisme scientifique et revolution
quantique: les premiers Conseils Solvay”
– submitted to Revue germanique internationale
CNRS, http://www.umn 8547. ens.fr/Series/
Rev.Germ.Internat.html.
I. Loris and C. Verhoeven, “On the applicability
of compressed sensing to ill-conditioned and
noisy systems” – VUB Techn. Report (2009).
Research carried out in the Group of the Deputy Director
149

150

Quantum Theory of Condensed Matter
Report of
the International
Advisory
Committee
Report of the International Advisory Committee
151

Report of the International Advisory Committee
Executive Summary
The committee has found that
o The Solvay Institutes are run in a most impressive and competent way.
o Within the existing organization there is not much room for a large extension of the
activities.
o The Solvay Meetings are the pearls in the activities and every effort should be spent
to uphold this level.
o The Solvay Workshops are held at very high scientific levels with excellent speakers
and participants.
o The Solvay Chairs and the Solvay Colloquia play a very important role for the universities
in Brussels to get exposed to world-class scientists.
o The Solvay Public Lectures are of utmost importance to foster interest in the most
modern science within the public mind.
o The Solvay Institutes play an important role by providing means for postdoctoral and
graduate student fellowships.
o The Solvay Institutes build an important bridge between the two language groups in
Belgium.
The committee has the following recommendations
o The Solvay Institutes should strive towards at least 50% funding from the endowment
to ensure long-time planning stability.
o The Solvay Institutes should broaden the scientific committee to also have members
from outside Brussels.
o The Solvay Institutes could increase slightly the number of workshops and try to cover
a broader spectrum of topics both in the workshops and the colloquia.
o The Solvay Institutes should take an active role in promoting new subjects to facilitate
for the universities to go into new modern areas.
o If new initiatives are taken they must carry the same excellence stamp as the other
programmes.
o The Institutes should try to open up towards bio-physics/bio-physical chemistry, which
are present in other departments than physics and chemistry. Issues in life science will
most certainly be driving much of science this century.
152

Introduction
The committee that consisted of Professors Lars
Brink (Göteborg), chair, Leticia Cugliandolo
(Paris), Gunnar von Heijne (Stockholm), Hermann
Nicolai (Potsdam) and Hirosi Ooguri (Pasadena)
met in Brussels on March 23 and 24, 2009.
Unfortunately Professor Jacques Prost (Paris)
was unable to attend the meeting. In order to
prepare ourselves we had obtained the annual
reports for the last three years together with
information about the budget. On March 23
we interviewed Professors Alexandre Sevrin
and Marc Henneaux and on March 24 we had
extensive interviews with Professors Barnich,
Craps, De Wit, Gaspard, Geerlings, Goldbeter,
Lambert, Wyns and again with Marc Henneaux.
Between and after the interviews and at the dinners
the committee had its deliberations.
The committee found that all interviewees were
very enthusiastic about the Solvay Institutes.
They are all committed to the cause to run the
various activities and to uphold the excellence
stamp that the name Solvay carries. Apart from
the secretariat, the work behind the activities is
performed on a voluntary basis within the academic
positions. This puts a limit as to how much
work the staff can do for the Solvay Institutes.
We will comment more on this fact later. Let us
first discuss the economy and go through the
various activities.
Economy
The committee was impressed by the fact that
the Institutes could be run on such a relatively
small budget. One reason is that the funding is
very efficiently used and another that the
universities contribute their share by paying for
the salaries of the academic staff and for the
localities. The committee is quite concerned
about the proportions in the budget. Only some
20% of the funding comes from the endowment.
For corresponding institutes the figure is
considerably higher. Even though most of the
remaining funding is secure on a long-time scale
it would be advantageous to strive towards a
funding from the endowment which is at least
50% to consolidate the financial base for the institutes.
This would make the long-term planning
much easier and would reduce the workload for
the director. We will remind that all the activities
around the Nobel Prizes including the prize
work and the prizes themselves are paid for by
the Nobel endowment.
Within the existing organization there is not
much room for a large extension of the activities.
If it is decided to increase an activity or to start a
new one it is crucial that the excellence level is
kept.
The committee will make some suggestions for
slight increases in the activities that should be
possible to implement with just a small budget
increase.
The Solvay Meetings
The committee can only congratulate the Institutes
for having re-established these meetings
at a level comparable to the famous ones of the
first half of the last century. The meetings are the
pearls in the activities and every effort should
be spent to uphold this level. These meetings are
unique in the scientific world.
The Solvay Workshops
Together with the meetings these workshops on
more restricted topical issues are the most
153
Report of the International Advisory Committee

Report of the International Advisory Committee
demanding activities. Three or four workshops
a year have been organized and the quality of
them has been very high. It is clear that the name
Solvay carries such weight that it is easy to get
top-level speakers and participants. With an
increased activity in chemistry we can foresee
a demand for a slight increase in the number of
such workshops. This can be achieved without
lowering the quality but it will require more work
from the staff. We will comment more on this fact
below.
The committee that decides about the workshops
as well as the Solvay chairs is a local
one from the two universities in Brussels. Even
though the workshops are regarded within
Belgium as a Brussels activity, from the outside
they are more regarded as a Belgian
activity. It would be advantageous to have a
broader base for the committee. In a first step
some members could come from other Belgian
universities and in a second step some
from outside Belgium, say from neighbouring
countries. Such a committee will bring in new
ideas, which will broaden the programme.
Adding external members would enhance the
authority of the committee and help to keep
up the excellence. It would be healthy to have
competing suggestions for workshops and it
would help the staff in Brussels if also people
from other Belgian universities sometimes take
responsibility for organizing a workshop.
They should still be held in Brussels and with
the short distances between Belgian cities
there shouldbe no problem for people from
other universities to both organize and participate
in the workshops.
Especially the chemistry community in Belgium
should be made more aware of the activities
and be encouraged to be involved in planning
and organizing workshops. The committee has
found that the name Solvay is more known for
excellence in scientific activities within the
physics community than in the chemistry one.
A number of high-level excellent workshops in
chemistry can change that. This should have a
high priority.
Solvay Chairs
This activity has been very successful so far. A
number of very distinguished scientists have
accepted to come to Brussels for a month or
two and in all cases they have brought a lot of
life, excitement and new knowledge into the
Belgian scientific community. We foresee a level
of at least one in physics and one in chemistry a
year. Since the aim should be to get the leading
scientists in the world it is more important to be
able to keep up the excellence than to expand
the programme too much.
With the broadening of the scientific committee
we foresee proposals of names representing
subjects not directly present in the departments
in Brussels. Such proposals should be encouraged
and sometimes the chairs could be used
to introduce the local scientific community to
new important subjects. This could be a way to
prepare the departments to open up into these
fields and make young researchers interested
in those subjects. In such cases it is of course
especially important to make sure that the chair
be well integrated into the host department.
Solvay Colloquia
The Solvay colloquia have by now been very
well established even though it seems that the
chemistry community has been slower to embrace
them. Again the committee is impressed
with the choice of lecturers and sees it as imperative
that the excellent level be maintained.
154

With a broader scientific committee we believe
in a broadening in the choice of subjects and
this activity can also be used to introduce the
local community to new important subjects.
This has certainly been done already, but the
committee should keep in mind its role in the
strategic planning of future activities in the
departments.
Colloquia are very important in the scientific
activities of a department. In the modern world
when the scientists get more and more duties it
is easy to skip a colloquium. That is not a good
solution though. An interesting colloquium
broadens the knowledge and introduces the
scientists to new ideas and techniques that
might be useful in the future. One way of getting
the whole faculty to attend a colloquium
is to let them meet the speaker both before the
event and after, to involve the whole department
in the activity. To get the graduate students
involved, a good idea could be to have
a free-lunch pre-colloquium with a local scientist
giving a background to the subject of the
colloquium.
Solvay Public Lectures
The Solvay public lectures have been of utmost
importance to foster interest in the most modern
science within the public mind. The lecturers
chosen have been extraordinary and the lecture
theatre has been full at every occasion. Even
though this is a very costly activity one cannot
overestimate its importance in the modern world
with so many temptations. It shows to the young
students the beauty of science and will help some
of them to contemplate a scientific career. It shows
to the common listener how advanced and how
fantastic modern science is, and it helps to demystify
the world and show that it is governed by
scientific laws which we can comprehend.
Solvay Graduate Programme
Recently the Solvay Institutes have got involved
in a graduate course programme in String
Theory together with Paris and Amsterdam. This
course is held for first-year graduate students
from the three cities and the students spend three
weeks in each city. This programme has been
very successful. The students get exposed to
very qualified teachers and they get a chance
to meet and work with the students from the
other two cities. The committee strongly believes
that this effort should be encouraged. A modest
contribution seems to be enough to have
the programme going. The committee would
encourage the Director to examine if this could
be called a Solvay Graduate Programme. This
would mean that the overall responsibility is
taken over by the Solvay Institutes.
Even though chemistry is divided into small
disciplines and it might be difficult to find enough
many first-year graduate students with common
interests, it should be known in the chemistry
community that the possibility of having a
Solvay Graduate Programme exists. It is imperative
though that such a programme must involve
excellent teachers and be held in a subject of
great importance. Again, collaboration with one
or more universities outside Belgium is desirable.
Post-doctoral and Graduate Student
Fellowships
The committee has noticed the great voluntary work
that many people on the faculty perform for the
Institutes. A good way of rewarding this work is to
finance either a graduate student or a post-doctoral
fellow for those persons. Apparently, within the Belgian
system of financing graduate students it is dificult
to find funding for foreign students in their first years
in Belgium. A grant from the Solvay Institutes can be
a handy way to overcome this problem.
155
Report of the International Advisory Committee

Report of the International Advisory Committee
If Solvay Institute funding is used for such positions
it is mandatory to ensure that the excellence
of the students match the status that the
name implies. The post-doctoral fellow or the
graduate student could be called ”Solvay fellow”
and ”Solvay graduate student” resp. to increase
the attraction of the positions.
Another scheme for fostering excellence in
Belgian science that the Institutes may wish to
contemplate is to advertise two ”Solvay Postdoctoral
Fellowships” one in physics and one in
chemistry, each year. The winners of the competition
should then get a position for five years
where it is mandatory that the first two or three
years be spent abroad and the remaining years
at an institution in Belgium. This would give
exceptionally gifted Belgian students a chance
to get postdoctoral training in the best universities
in the world for a longer period and then be
given enough time back home to get established
in the Belgian system.
Staff and Support for the Director
The committee has understood that the success
of the Solvay Institutes rests heavily on the tireless
and excellent work that the Director and the
secretaries perform. Also the enthusiasm of the
other persons involved is necessary for the success.
The board should be aware that within the
present set-up one is close to the limit for what
can be achieved. As the staff becomes more
and more experienced a modest increase in the
number of workshops could be accommodated
but any new activities will have to be balanced
against the administrative load.
The committee finds the workload of the
Director to be extremely heavy. Not only does
he have to actively work for the funding of the
Institutes and oversee all the activities but also
take a very active role in the daily running of
the Institutes. It would probably be advantageous
if the Director could be helped in his
endeavour by a Deputy Director with clear
administrative responsibilities. This would
allow the Director to concentrate on the more
strategic work. If such a Deputy Director is appointed
she/he should preferably be chosen
from a field that is complementary to the one
of the Director.
A very important aspect of all the activities is
the documentation on internet. To promote
the activities and to lighten the burden for the
secretariat an efficient system for registration
and communication with lecturers and participants
in meetings and workshops is mandatory.
Some external professional help is probably
necessary to implement such systems. The
normal running of the web pages is performed
very expertly by the staff. At some stage an
efficient search engine would be needed. That
would also demand an extra effort both in
workload and in costs.
The Solvay archives contain material of
utmost importance for the history of science.
In some respects they are unique in the
world containing correspondences between
some of the most important figures in the
history of science. The Institutes should try
to set up a programme financed outside the
normal budget where all this material be
made available to the general public. Also
the lectures and discussions at the Solvay
meetings should be made available. One
can here compare with the Nobel archives,
which are increasingly made available on
internet (apart from the ones which are still
confidential.) It would be advantageous to
have as much as possible of this done before
the anniversary in 2011.
156

Benefits for the Belgian Community
During the discussions with the staff and the Director
the committee became well aware of the
important bridge that the Solvay Institutes build
between the two language groups in Belgium.
The commitment to this cause is very strong and
we heard appreciations for it from many corners.
These efforts will of course continue but it is important
for the board to be well aware of it and
support it.
The Institutes can also build new bridges between
physics and chemistry. The overlap does not
seem to be too strong now, and the Institutes can
take advantage of having physics and chemistry
together under the same board and director.
The committee also noted that bio-physics/biophysical
chemistry does not seem to be present
in the physics or chemistry department but in
the biology and to some extent in the medicine
departments. The Institutes should try to open
up towards those directions and get them more
integrated in the work.
The institutes should also use its position to
introduce new important fields in physics and
chemistry to the universities. In the end it is the
departments and the universities that decide about
future directions but the activities of the Solvay
Institutes should help them in these decisions. This
is another important role for the Solvay Institutes
within the Belgian scientific endeavours.
Conclusions
The committee is well aware of the differences
between physics and chemistry. In physics the
most basic questions about our world are raised
and the Solvay meetings became famous precisely
for raising those issues. This is still true for
the modern Solvay meetings. Physics also has a
long list of heroes with Albert Einstein and Niels
Bohr as the top figures. They are all well known
by everybody and their association with Solvay
meetings are equally well known. In contrast,
the great achievements in chemistry are not as
well appreciated by the general public, and the
Institutes have to keep this in mind when planning
their activities.
On the other hand chemistry is closer to the
industrial activities and those industries have
played a vital role in Belgium. Opening up
towards the interfaces between physics, chemistry
and biology could bring in basic questions
about life, issues that will most certainly be
driving much of science this century. Here the
different Solvay activities could play a decisive
role in the contemporary world.
One experience from recent Solvay Conferences
and Workshops that the committee noted is that
while the physicists want to have all the talks
directly available on the internet, the chemists
often want to have meetings between closed
doors, being afraid that intellectual property
rights might otherwise become compromised or
that important new ideas might be exploited by
competing groups. The Institutes have to keep
this in mind when making information available.
The overall impression that the committee has
obtained is that the Solvay Institutes are run
in a most impressive and competent way. It is
remarkable that the director and his staff have
re-established the Institutes as world-leading
institutions so swiftly, and the committee can only
congratulate Belgium and the scientific communities
in physics and chemistry to this achievement.
Göteborg Paris Stockholm Potsdam Pasadena
Lars Brink Leticia Cugliandolo Gunnar von Heijne Hermann Nicolai Hirosi Ooguri
157
Report of the International Advisory Committee

158