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<DIV><FONT size=2 face=Arial><FONT size=3 face="Times New Roman">El miércoles 29
de mayo tendrá lugar un encuentro en el que disertarán dos<BR>reconocidos
filósofos de la física brasileños. Décio Krause (Depto.<BR>Filosofía, Univ.
Federal de Santa Catarina) hablará sobre "Why (and how)<BR>to question identity
in Quantum Mechanics?" y Osvaldo Pessoa Jr. (Depto.<BR>Filosofía (FFLCH),
Universidad de San Pablo) sobre "Interpreting the<BR>Afshar Setup and other
experiments in Quantum Physics".<BR><BR>El encuentro se realizará a partir de
las 15 hs. en el aula 5 del Pabellón<BR>2. A continuación incluimos una síntesis
de ambas presentaciones.<BR><BR><BR>Why (and how) to question identity in
Quantum Mechanics?<BR>Décio Krause<BR><BR>It is a fact that quantum mechanics
(QM) can be developed within a<BR>mathematical framework involving the standard
theory of identity (STI). It<BR>has been treated this way ever. But the
implications of STI wouldn't go<BR>unnoticed by philosophers interested in
foundations. The main consequence<BR>of STI is that every object is an
individual, in the sense of being<BR>distinct from any "other" individual. This
is a theorem of the underlying<BR>logic, mainly if we are dealing with finitely
many objects, as physics<BR>seems to do. Hence, in particular, Leibniz Principle
of the Identity of<BR>Indiscernibles is a theorem, and cannot be questioned
(under the<BR>hypothesis of consistency). But QM seems to present us situations
where<BR>quanta cannot be distinguished in any way, as entangled systems seem
to<BR>show. Before measurement, we cannot speak of the individuality of
the<BR>involved objects. Thus, logic (that is, the "classical"
underlying<BR>mathematical apparatus) forces us to assume that there are
"logical"<BR>hidden variables of some kind, for if the differentiation of quanta
cannot<BR>be done by physics, it is a result of the underlying logic. In my work
I<BR>have trying to find a way to assume a metaphysics of
"non-individuals",<BR>entities that defy STI, but that can be collected into
amounts having a<BR>cardinal but not an associated ordinal (that is, there may
be many of<BR>them, but they sometimes cannot be discerned in any way, counted,
put in<BR>some order, etc.). The conclusion is that STI brings inconveniences
for<BR>the foundational analysis of QM. What I propose is to build a QM within
a<BR>different mathematical framework where STI doesn't hold, where quanta
can<BR>be treated as legitimate indiscernible things, without the
usual<BR>mathematical tricks of assuming permutational symmetries of a
kind.<BR><BR><BR>Interpreting the Afshar Setup and other experiments in Quantum
Physics<BR>Osvaldo Pessoa Jr.<BR><BR>Interpretations of quantum theory may be
classified according to an<BR>epistemological criterion (positivist or realist)
and an ontological one<BR>(corpuscular, undulatory, dualist, or without
ontology), besides an<BR>intentional-emotional aspect. We characterize five
general groups of<BR>interpretations, and analyze how they explain certain basic
experiments.<BR>Special emphasis will be given to the Afshar experiment, and
the<BR>refinements it introduces to the complementarity
interpretation.<BR><BR><BR>Saludos cordiales,<BR><BR>Secretaría
Académica<BR>Facultad de Ciencias Exactas y Naturales<BR>Universidad de Buenos
Aires</FONT><BR><BR></FONT></DIV></BODY></HTML>