-17 novembre 2003, 9h30-12h30, salle de l'AX (Association des Anciens Elèves de l'Ecole Polytechnique, 5 rue Descartes, 75005 Paris) [Organisation Alexei Grinbaum]
Carlo Rovelli (Université d'Aix-Marseille et Université de Rome)
"Relational Quantum Mechanics"
Abstract:
The debate on what precisely quantum theory is telling us about
the world is raising again increasing interest. The meaning of
the theory is uncontroversial as far as the theory is applied
to microsystems interacting with classical macrosystems. But opinions
diverge sharply about how, or even whether, the theory describes
all physical systems. I present some considerations on this issue,
and a tentative point of view. I argue that if we trust the empirical
adequacy of the theory, we are lead to conclude that all contingent
properties of a physical system can only be interpreted as relative
to another physical system, interacting with the first. The theory
deals with the information about future interactions that can
be gathered, in principle, from past interactions. Information
from different systems can be compared, but does not allow us
to hypostatize that systems have an absolute state, nor that physical
events have absolute reality. I suggest that the discovery of
this physical limitation is the lesson from experimental microphysics
which is coded in the formalism of quantum theory.
Michel Bitbol (CREA/CNRS, Paris)
"Réponse sur la mécanique quantique relationnelle"
Résumé:
L'interprétation relationnelle de la mécanique quantique
de Carlo Rovelli a des points communs à la fois avec la
lecture de Bohr et avec l'interprétation des états
relatifs d'Everett. On montre cependant qu'elle leur est aussi
symétriquement opposée, car elle va plus loin que
chacune d'entre elles dans la dénonciation de certains
"absolus" ou "reifications" présupposés
par la théorie physique. La mécanique quantique
relationnelle de Rovelli n'est cependant pas elle-même exempte
de toute absolutisation: elle absolutise implicitement le "point
de vue des points de vue" à partir duquel elle décrit
le réseau de relations entre systèmes physiques
supposés définir les états quantiques.
-8 décembre 2003, 14h-17h, salle de l'AX (Association des Anciens Elèves de l'Ecole Polytechnique, 5 rue Descartes, 75005 Paris). [Organisation Alexei Grinbaum]
Christopher Fuchs (Bell Laboratories, Lucent Technologies et Dublin Institute of Technology)
"What is the Difference between a Quantum
Observer and a Weatherman?"
Abstract:
Not much. But where there is a difference, there lies quantum
theory's most direct statement about properties of the world all
by itself (i.e., the world without observers or weathermen). In
this talk, I will try to make sense of the last two sentences.
Philippe Grangier (Institut d'optique, Orsay)
"Contextual objectivity : an experimentalist's
view on the foundations of
quantum mechanics"
Abstract :
An attempt is made to formulate quantum mechanics (QM) in physical
rather than in mathematical terms. It is argued that the appropriate
conceptual framework for QM is "contextual objectivity",
which includes an objective definition of the quantum state. This
point of view sheds new light on topics such as the reduction
postulate and the quantum measurement process.
-14 Janvier 2004, 9h30-17h30, Amphithéâtre Stourdzé, entrée 25, rue de la montagne Sainte-Geneviève
JOURNEE "Ontologie et objectivité en physique quantique"
-5 mars 2004, 18h00, CREA salle 315 , entrée 25, rue de la montagne Sainte-Geneviève
Christian de Ronde (Center Leo Apostel, Brussels, Belgium )
"Historical Development of the Modal Interpretations: Monism and Relationalism".
Abstract:
Modal interpretations have been developed since the early '70
by a growing group of physicists and philosophers as a way out
of the measurement problem. It is a no collapse interpretation
in which properties are assigned to systems. From this characteristic
it steams its realistic flavor.
I will present a review of the historical development of modal
interpretations analyzing some of its main characteristics and
specifically the ontology which derives from each interpretation.
In this historical development several no-go theorems play a significant
role as a road sign towards a perspectival version of the modal
interpretation (Bene and Dieks 2002). I will end my seminar with
a study of this perspectival interpretation and its possible development.
-5 Avril 2004, 17h00, CREA salle 315 , entrée 25, rue de la montagne Sainte-Geneviève [Organisation Alexei Grinbaum]
Andrei Khrennikov (International Center for Mathematical Modeling in Physics and Cognitive Sciences, University of Vaxjo, Sweden)
"Contextual approach to quantum mechanics and the theory of the fundamental prespace"
Abstract:
We constructed a Hilbert space representation of a contextual
Kolmogorov model. This representation is based on two fundamental
observables -- in the standard quantum model these are the position
and momentum observables. This representation has all distinguishing
features of the quantum model. In particular, Kolmogorov random
variables are represented by noncommuting operators. However,
our representation is not standard model with hidden variables.
In particular, this is not a reduction of the quantum model to
the classical one. In our model both classical and quantum spaces
are very rough images of PRESPACE. We cannot say so much about
algebraic and topological structure of prespace, since we operate
only with probabilistic pictures of this space.
References:
A. Yu. Khrennikov, Representation of the Kolmogorov model having
all distinguishing features of quantum probabilistic model. {Phys.
Lett. A}, {bf 316}, 279-296 (2003).
A. Yu. Khrennikov, Interference of probabilities and number field
structure of quantum models. {Annalen der Physik,} {bf 12}, N.
10, 575-585 (2003).
-16 Juin 2004, 9h30-17h30, Amphithéâtre A, Bâtiment Joffre, 1. Entrée par le 25, rue de la Montagne Sainte-Geneviève