IIP News 04
The IIP is a research institute with an international vocation, permanently facing the frontier areas of theoretical physics. Its mission is to intensify the exchange of scientific knowledge with the international community and, in particular with the Latin American community, being a pole unifying national strategic areas of theoretical physics.
The IIP is a research institute with an international vocation, permanently facing the frontier areas of theoretical physics. Its mission is to intensify the exchange of scientific knowledge with the international community and, in particular with the Latin American community, being a pole unifying national strategic areas of theoretical physics.
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news<br />
INTERNATIONAL<br />
INSTITUTE OF<br />
PHYSICS<br />
Natal,<br />
June 2017<br />
Year II Number <strong>04</strong><br />
<strong>IIP</strong> HOSTS WORKSHOP ON COLLECTIVE SPIN<br />
TRANSPORT IN ELECTRICAL INSULATORS<br />
Interview with<br />
Rogerio Rosenfeld<br />
Professor Rogerio Rosenfeld visited the <strong>IIP</strong><br />
last May to present a colloquium on the<br />
developments in the Dark Energy Survey project<br />
and talked with the <strong>IIP</strong> news about his career<br />
and the novelties in particle physics.<br />
LIGO presents its third<br />
detection<br />
The Laser Interferometer Gravitational-wave<br />
Observatory (LIGO) detected a third gravitational<br />
wave event, showing that a new window in astronomy<br />
has been firmly opened.
2<br />
<strong>IIP</strong> <strong>News</strong> - Year II, number <strong>04</strong><br />
<strong>IIP</strong> hosts workshop on Collective Spin<br />
Transport in Electrical Insulators<br />
From April 24 to May 26 the <strong>IIP</strong> hosted the<br />
workshop Collective Spin Transport in Electrical<br />
Insulators, when researchers from different<br />
countries gathered to discuss the latest’s<br />
achievements in the fields of spintronics.<br />
“The program of the event was very good,<br />
because it left Mondays and Tuesdays for lectures,<br />
leaving the rest of the days of the week<br />
for creating new collaborations. This is very<br />
important, specially for us in Brazil, who don’t<br />
have much contact with foreign researchers”,<br />
Said Denis Candido, one of the participating<br />
students.<br />
The central topics of the program included<br />
collective spin transport, quantum correlations,<br />
novel quantum heterostructures and<br />
more.<br />
This workshop allowed theoretical and experimentalists<br />
could work together when<br />
approaching the main questions in the field<br />
of Collective Spin Transport in Electrical Insulators<br />
and present new alternatives to the<br />
problems of the area. A particularly good opportunity<br />
to researchers looking for new directions<br />
in their careers.<br />
According to Professor Carlos Egues (University<br />
of Sao Paulo, Brazil), one of the event’s<br />
director, “this was a very productive event.<br />
The impression that I had was that people interacted<br />
more during this program. I started<br />
in a new collaboration with one of directors<br />
during the event and I saw the same happening<br />
with others participants. One year from<br />
now I hope to see papers as a result of the<br />
conference”.<br />
The full record of lectures are available in the <strong>IIP</strong><br />
Youtube channel (www.youtube.com/iiptv).<br />
Event director, Professor Carlos Egues (USP)<br />
Professor Riccardo Sturani
June, 2017 3<br />
Interview with Prof. Rogerio Rosenfeld<br />
Researcher from the Sao Paulo State University, Professor Rogerio Rosenfeld is involved in the<br />
Dark Energy Survey project, in search for an answer to what are dark energy and dark matter.<br />
He visited the <strong>IIP</strong> last April to present a colloquium about this subject and talked with the <strong>IIP</strong><br />
news about his career and the work he us up to today.<br />
<strong>IIP</strong> - Tell us about your career.<br />
RR - I started my career in elementary particles at the<br />
University of Sao Paulo. My master thesis was on particles<br />
called axions, which until today have not been detected,<br />
neither they have been eliminated, which is great (laughs),<br />
since nowadays, many particles are being eliminated. After<br />
USP I went to do my PhD in particle physics at the University<br />
of Chicago.<br />
In Chicago I actually worked on Higgs boson, or more<br />
generally, with the sector of spontaneous symmetry<br />
breaking. The Standard Model (SM) of elementary particles<br />
needs a mechanism that gives mass to the particles. This<br />
mechanism comes from a breaking of the “electroweak”<br />
symmetry and the Higgs boson is a consequence of this.<br />
At that time, there was no information about the Higgs<br />
boson and there was a possibility that the sector, which<br />
breaks the symmetry is a sector that is what we call<br />
strongly coupled. My studies then implied that the Higgs<br />
boson would be very heavy.<br />
<strong>IIP</strong> - That didn’t happen?<br />
RR - This did not happen. As was the case with many other<br />
theories, my work did not apply to SM physics, because the<br />
Higgs boson discovered in 2012, is not really very heavy.<br />
It has a mass of approximately 123 times the mass of the<br />
proton.<br />
<strong>IIP</strong> - What was it like to be at CERN when the Higgs boson<br />
was announced?<br />
RR - I was spending a sabbatical, from October 2011 to<br />
October 2012 at CERN. Though I knew there was a great<br />
possibility of having this discovery, it was also a great luck!<br />
The LHC is an extremely complex machine. In 2009, when<br />
it was just starting, there was an explosion of some of the<br />
superconducting magnets. That delayed the program by a<br />
year or two.<br />
I was in doubt where to go. I wanted to be in the place<br />
where the Higgs would be discovered, and there was a<br />
competing experiment, with less energy, in a US laboratory<br />
called Fermilab. It was at an accelerator called Tevatron,<br />
which was also looking for the Higgs boson. So when I<br />
had to make my decision, it was not clear that the LHC<br />
was going to work fine while the Tevatron was running<br />
perfectly. It was not easy.<br />
I must say that my wife was the most important factor<br />
because she said “Fermilab no! I’ve been there. Let’s go<br />
to a different place” (laughs). Everything went well. The<br />
Tevatron closed down in 2011 because it could no longer<br />
compete with the LHC and the Higgs boson discovery was<br />
Photo by Juliano Lima Barreto<br />
Professor Rosenfeld talks to UFRN students at the <strong>IIP</strong><br />
really a historical moment.<br />
The announcement came out in July 2012 and it was an<br />
incredible euphoria. In the first place I could not get into<br />
the auditorium where the announcement was made. I got<br />
there around 05:00 in the morning. I think it opens at 10<br />
o’clock – and people was already there. It was summer and<br />
you have summer students, who spend a month at CERN.<br />
The students camped in front of the auditorium. I could not<br />
compete (laughs).<br />
<strong>IIP</strong> - Besides the Higgs boson, the LHC was designed to<br />
look for other new particles. Could you tell us about<br />
supersymmetry, and why it is searched at the LHC?<br />
RR - What is supersymmetry? It is a symmetry that says<br />
that for every particle of the SM there is a “super-partner”.<br />
One reason, why supersymmetric models are interesting is<br />
that they avoid sensitivity of the theoretical mass of the<br />
Higgs to the details of the model at high energies in a<br />
natural way. Natural means that we can swallow this idea<br />
without big hiccups (laughs).<br />
But anyway, the masses of the superpartners should be of<br />
the order of some teraelectronvolts, a thousand times the<br />
mass of the proton. This is also the range of energy, where<br />
the LHC can discover these particles. Alas, so far they<br />
have not been discovered. This leads to these conceptual<br />
problems of naturalness or fine-tuning. It means that we<br />
have to very carefully adjust the parameters of our theory<br />
to ensure that the mass that we measure today is where<br />
it is, and not at some very large energy scale (like Planck<br />
scale).<br />
<strong>IIP</strong> - So, can we conclude that supersymmetry will not be<br />
discovered?<br />
RR - No. Supersymmetry is a kind of theory you cannot
4<br />
fully eliminate. Why? Because you do not know its scale.<br />
We know that supersymmetry is not an exact symmetry of<br />
nature, it has been broken. So it’s a matter of knowing at<br />
which scale this happens. So far we do not have an answer<br />
to that.<br />
It is possible that supersymmetry can be valid only at the<br />
Planck scale. It is very important for string theory and<br />
we may still find that supersymmetry has relevance at<br />
energies lower than the Planck scale. However, the main<br />
motivation was the solution of this problem of fine-tuning<br />
and, apparently, supersymmetry is not responsible for that.<br />
<strong>IIP</strong> - Another possible new physics is related to Dark Matter<br />
and Dark Energy. What is the difference between them?<br />
RR - With both dark matter and dark energy our evidence<br />
is mostly astronomical and cosmological. Dark matter<br />
is kind of a normal matter, only it does not interact with<br />
light. It has a normal gravitational effect and this is why<br />
it was detected. About 99% of physicists, including myself,<br />
believe that dark matter is a new type of particle that does<br />
not interact with light and has to be stable or have a very<br />
large half-life time comparable to the age of the Universe<br />
because it has not decayed so far. In the Standard Model<br />
there are no candidates for dark matter and so far we have<br />
no clue what it is.<br />
Dark energy is totally different. First, it is a more diffuse<br />
thing - we do not believe it is a particle. Moreover its<br />
gravitational effects is, in a sense, opposite to that of dark<br />
matter. Dark energy has in fact a repulsive effect. It acts like<br />
an antigravity.<br />
The simplest scenario is the cosmological constant. It<br />
was introduced by Einstein in 1917. He wanted to apply<br />
the theory of gravity, which he developed in 1915 for the<br />
Universe as a whole, but he needed a repulsive force to<br />
keep gravitating matter from collapsing. Back in 1917 it<br />
was believed that our galaxy was the whole Universe, and<br />
the stars had fixed stable positions in it. Einstein realized<br />
that he could introduce a repulsive force through the<br />
cosmological constant.<br />
With the discovery of Hubble’s expansion of the Universe in<br />
1929, there was no longer a need for cosmological constant<br />
because the Universe was not static.<br />
With no cosmological constant the expanding Universe<br />
would resist the collapse, but the rate of the expansion<br />
would be decreasing, as if I throw a thing up, it goes, goes,<br />
Photo by: Luiz Barcelos<br />
Professor Rosenfeld at his book signing event<br />
but the speed is decreasing.<br />
<strong>IIP</strong> <strong>News</strong> - Year II, number <strong>04</strong><br />
In 1998 there came a great surprise. It was measured<br />
that the expansion of the Universe is accelerating.<br />
Nobody knew why, but they obviously remembered the<br />
cosmological constant. Currently, dark energy is dominant<br />
in the Universe. Our atoms are only 5% of the Universe<br />
and 25% is dark matter.<br />
<strong>IIP</strong> - You are involved in the Dark Energy Survey project.<br />
What is it?<br />
RR - As I said, my background is in particle physics and I<br />
continue to work with particle physics, but I’ve always liked<br />
cosmology, and 10-15 years ago I started working with it<br />
from the theoretical side. Besides, I got an opportunity to<br />
participate in an experimental project. I found this to be<br />
super cool. There is a group at the national observatory<br />
in Rio de Janeiro that is participating in this Dark Energy<br />
Survey project from the beginning.<br />
The Dark Energy Survey (DES) itself is a international<br />
project with 300/400 participants around the world, led<br />
by the Fermilab. They started investing in this connection<br />
between particle physics and the Universe.<br />
The idea is to map the Universe. The Sloan Digital Sky<br />
Survey, another Fermilab project, covers 1 million galaxies.<br />
The SDS will covers 300 million.<br />
We use a 600 megapixel digital camera, installed in a 4<br />
meter telescope in Chile. This camera takes pictures of<br />
the sky using five different filters, which is different from<br />
the Sloan. Although DES is much less accurate, it gets 300<br />
times more galaxies.<br />
The idea is that dark energy influences the formation of<br />
the Universe, so if you look at the distribution of galaxies<br />
you may have information about dark energy.<br />
<strong>IIP</strong> - Besides particles you also worked in econophysics.<br />
What was your experience?<br />
RR - When I was in Chicago, I met some people who<br />
worked with economics and finances. Many physicists<br />
were converting to finance. During my second postdoc<br />
I was starting to get worried about employment, so I<br />
started to read some things.<br />
When I came back to Brazil I found a group that was<br />
studying applications of physics in economics. At that time<br />
it was about dynamical systems applied to economics. In<br />
particular, it was very fashionable to talk about chaos, in<br />
application to economics. Thus I began to interest myself<br />
in mathematical modeling of financial systems.<br />
I ended up losing interest, because in the financial market<br />
in recent years it has become important what they call<br />
high frequency trading. Operations on the stock market<br />
occur at microsecond scales, so people have begun to<br />
work on appropriate algorithms instead of those more<br />
elegant theories. It’s called algorithm trading and I don’t<br />
have more time to do this.<br />
In general, however. I think it’s cool that people we train<br />
in physics also have a possibility to work in, for example,<br />
financial modeling, risk control etc.
June, 2017 5<br />
LIGO presents its third detection<br />
By Riccardo Sturani<br />
<strong>IIP</strong> Associated Professor<br />
The Laser Interferometer Gravitational-wave Observatory (LIGO) detected<br />
a third gravitational wave event, showing that a new window<br />
in astronomy has been firmly opened. Similarly to the first two detections,<br />
the waves were generated by the inspiral of two black holes<br />
which eventually collided to form a larger black hole.<br />
The newfound black hole, formed by the merger, has a mass about 49<br />
times that of our sun, filling the gap between the masses of the two<br />
merged black holes detected previously by LIGO, with solar masses of<br />
62 (first detection) and 21 (second detection).<br />
LIGO made the first-ever direct observation of gravitational waves in<br />
September 2015 during its first observational run since undergoing major upgrades in a program<br />
called Advanced LIGO. The second detection was made in December 2015. The third detection,<br />
dubbed GW1701<strong>04</strong> and made on January 4, 2017, is described in a new paper accepted for publication<br />
in the journal Physical Review Letters.<br />
The last detection was the farthest yet, located around 3 billion light-years away from the earth.<br />
This experiment helped us to know more about the population of “solar mass” black holes with 20<br />
times the mass of our sun or more, which have not been observed before LIGO detections.<br />
The detections have been made by the twin LIGO detectors, located in the US, one in Hanford in the<br />
Washington state, and one in Livingston, Louisiana state, and they are run by Caltech and MIT. More<br />
than one thousand researchers are part of the LIGO Scientific collaboration, affiliated to a number of<br />
University and research organizations around the world.<br />
In all three cases of the detections made so far, black holes collisions produced an instantaneous<br />
luminosity in gravitational waves larger than the average electromagnetic luminosity of the entire<br />
Universe.<br />
The most recent observation allows to know partial information about the spin of the black holes, i.e.<br />
about the direction of rotation of the individual black holes composing the binary system.<br />
Black holes may rotate in the same or opposite directions with respect to their orbital motion, and<br />
despite the data do not allow to draw definite conclusions, they indicate that at least one of the two<br />
black holes had its rotation axis aligned in the opposite direction than the orbital rotation axis. The<br />
actual inclination of the rotation axis could not be determined, as information about spin direction<br />
would allow to distinguish the binary system formation channel: if from a pre-existing star binary<br />
system or if black holes formed first and then met each other to form a bound system. The detected<br />
indication for misalignment favours formation of binary system from pre-existing black holes in dense<br />
globular cluster.<br />
Moreover a new test of Einstein’s theory of General Relativity has been performed on this event.<br />
Gravitational waves of different frequencies may travel with different speed, a possibility forbidden<br />
by General Relativistic theories but allowed in many of its extensions, much in the same way as light<br />
when travelling in a medium like glass. LIGO did not find any evidence of such an effect, which would<br />
have been stronger in this event rather than in the previous ones since it happened at a distance<br />
roughly twice larger than the two previous ones.<br />
The work in the LIGO project continues, as data taking are currently ongoing, soon to be in coincidence<br />
with the Italo-French detector VIRGO, and new upgrades on all the detectors are scheduled to start<br />
later in 2017 to prepare the next run which should start around the end of 2018/beginning 2019.
6<br />
<strong>IIP</strong> <strong>News</strong> - Year II, number <strong>04</strong><br />
New Journal Club on entropic matters<br />
A new series of presentations has been launched at the <strong>IIP</strong>, gathering the institute researchers and other<br />
members of the local scientific community. The main idea behind this journal-club style event is to discuss<br />
interdisciplinary connections brought by the notion of quantum entanglement. Those include quantum<br />
coherence, locality, black holes and quantum gravity. The “Entropic Connections” journal club started its<br />
activities last March and have already approached some very exciting recent developments in the subject<br />
highlighted by articles in top scientific journals .<br />
According to the <strong>IIP</strong> researcher, Dr. Fabio Novaes, the idea came up from a conversation between him and<br />
one of the new <strong>IIP</strong> post-docs who asked if the Institute had already had any journal club.<br />
“We always have seminars and colloquiums, but normally presented by visitors. Based on this I started talking<br />
with some other people here and proposed to have a journal club. The idea is to have presentations about<br />
the latest issues in modern physics, presented in a very accessible way to our scientists”, said Dr. Novaes.<br />
Every two weeks a member of the Institute’s research team will talk about some new subject that he or she<br />
finds interesting to be addressed, discussing it with other members and visitors of the <strong>IIP</strong> in an open and<br />
informal environment.<br />
<strong>IIP</strong> welcomes new researchers<br />
A new group of post-doctoral researchers<br />
arrived in the <strong>IIP</strong> during the last month of<br />
April, and have already plunged into the different<br />
research activities at the Institute. The<br />
new members will be representing the fields<br />
of quantum information and foundations of<br />
quantum mechanics, strongly correlated systems<br />
in condensed matter physics as well as<br />
string theory and high energy physics.<br />
Doctors Diego Pires, Romulo Rougemont,<br />
Jacques Pienaar, Flavia Ramos, Sebastien<br />
Eliens, Giancarlo da Silva and Ashutosh Rai<br />
are collaborating with researchers from the<br />
<strong>IIP</strong> and other institutions in Brazil and abroad.<br />
“I think that the infrastructure and the modus<br />
operandi of the <strong>IIP</strong> are completely different<br />
from what those of us who did post-graduation<br />
in Brazil, had experienced before. At<br />
post-graduate level, you won’t find an institute<br />
in the country with the organization<br />
of activities such as that at the <strong>IIP</strong>”, said Dr.<br />
Pires.<br />
Most of these researchers learned about the<br />
Institute during their previous visits to Natal,<br />
participating in one of the many international<br />
events organized by the <strong>IIP</strong>.<br />
“I first visited Natal in 2013, during a workshop<br />
held by the <strong>IIP</strong>. So when I ran across an<br />
add about open positions, posted in an SBF<br />
(Brazilian Physics Society) bulletin, I favored<br />
the offered conditions and applied for the<br />
position”, said Dr. Rougemont.<br />
The <strong>IIP</strong> regularly opens new post-doctoral positions.<br />
Interested candidates are encouraged<br />
to learn more about it at www.iip.ufrn.br.
Next Schools & Workshops<br />
June, 2017 7<br />
Next Conferences<br />
Workshop Black Holes Across the Scales<br />
July 31 to August 18, 2017<br />
IX Brazilian Meeting on Simulational Physics<br />
(BMSP)<br />
August 21 to 25, 2017<br />
Workshop Out of Equilibrium Dynamics in Soft<br />
and Condensed Matter<br />
August 28 to September 10, 2017<br />
Workshop Finite Systems in Nonequilibrium: From<br />
Quantum Quench to the Formation of Strong<br />
Correlations<br />
September 07 to 30, 2017<br />
Workashop Magnetic Fields in the Universe VI:<br />
From Laboratory and Stars to the Primordial<br />
Structures<br />
October 16 to 20, 2017<br />
Workshop LHC Chapter II: The Run for New Physics<br />
November 06 to 17, 2017<br />
Contact us at press@iip.ufrn.br to receive news about our seminars and colloquia in your email.
8<br />
<strong>IIP</strong> Photo Galery<br />
<strong>IIP</strong> <strong>News</strong> - Year II, number <strong>04</strong><br />
<strong>IIP</strong> events in May<br />
INTERNATIONAL<br />
INSTITUTE OF<br />
PHYSICS<br />
Visit our website to know more about our programs and events:<br />
www.iip.ufrn<br />
To see the guidelines for scientific proposals at the <strong>IIP</strong> visit:<br />
www.iip.ufrn.br/proposalsforeventsdetail<br />
Follow the <strong>IIP</strong> activities in our Facebook page:<br />
www.facebook.com/iipufrn<br />
Subscribe to our Youtube chanel:<br />
www.youtube.com/iiptv<br />
<strong>News</strong>letter produced by the <strong>IIP</strong> Communication Office.<br />
Contact us at:<br />
+55 (84) 3342-2249 (ext. 208) / press@iip.ufrn.br.