2000 HSS/PSA Program 1 - History of Science Society

David MacCallum Carleton College
PSA Abstracts
Quantum Entanglement and Classical Computations
There are computational tasks that can shown to be ‘easy’ for a quantum computer,
even though they appear to be ‘hard’ for all classical computers. This increased
computational power is based on a form of parallelism in quantum computation
that requires entangled states. This use of entangled states appears to conflict
with the classical models of computation developed by mathematicians and
logicians. I will argue that, in an important sense, the physical processes we call
quantum computations are not classical computations. However, I do think that
we are justified in calling them computations. Thus, quantum computation gives
us a good reason to generalize our mathematical models of computation.
Eric Martin University of New South Wales
Daniel Osherson Rice University
Scientific Discovery from the Perspective of Hypothesis Acceptance
A model of inductive inquiry is defined within the context of first-order logic.
The model conceives of inquiry as a game between Nature and a scientist. To
begin the game, a nonlogical vocabulary is agreed upon by the two players,
along with a partition of a class of countable structures for that vocabulary.
Next, Nature secretly chooses one structure (the real world) from some cell of
the partition. She then presents the scientist with a sequence of facts about the
chosen structure. With each new datum the scientist announces a guess about
the cell to which the chosen structure belongs. To succeed in his inquiry, the
scientist’s successive conjectures must be correct all but finitely often, that is,
the conjectures must converge in the limit to the correct cell. Different kinds of
scientists can be investigated within this framework. At opposite ends of the
spectrum are dumb scientists that rely on the strategy of induction by enumeration,
and smart scientists that rely on an operator of belief revision. We report some
results about the scope and limits of these two inductive strategies.
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James Mattingly Indiana University
Singularities and Scalar Fields. Matter Theory and General Relativity
Philosophers of physics should be more attentive to the role energy conditions
play in GR. I review the changing status of energy conditions for quantum
fields presently there are no singularity theorems for semiclassical GR.So we
must reevaluate how we understand the relationship between GR, QFT and
singularities. Moreover, on our present understanding of what it is to be a
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