Vendredi 26 novembre, de 14h00 à 17h45
L'IMéRA propose une rencontre sur le thème "Aspects probabilistes et fondements de la théorie quantique"

14h00
Pierre LIVET, Sandro VAIENTI
Introduction

14h15 -15h00 : Jean BRICMONT
Why does nonlocality support Bohm's theory

The goal of the talk will be to discuss the conceptual problems of quantum mechanics, emphasizing an ambiguity in the traditional formulation, concerning the meaning of the wave function. The main novelty discovered by quantum physics, i.e. the nonlocality of the universe implied by Bell's theorem, will also be discussed. Moreover, we will explain why this nonlocality supports a completion of the quantum formalism due to David Bohm.

15h00-15h15 : Discussion

15h15-16h00 : Thomas DURT
About Zurek's Quantum Darwinist Approach to the Measurement problem
Zurek did a lot to promote the decoherence approach. The decoherence approach is an essential ingredient in several ``no-collapse'' interpretations of the Quantum Theory (for instance in the Bohmian interpretation, the modal interpretation and the many worlds interpretation).
Nevertheless, although it is very succesful in explaining why it is impossible FAPP to observe coherent superpositions of macroscopically distinguishable states (``Schroedinger cats''), it doesn't solve by itself the measurement problem. Zurek proposed, in the framework of the Quantum Darwinist Approach to the Measurement problem, an extra-argument for completing the task, the so-called Environment Induced Selection Rule.
Our aim is to discuss advantages and drawbacks of this approach, and also to establish some comparisons with other interpretations.

16h00-16h15 : Discussion

16h15-16h30 : Pause-café

16h30-17h15 : Simon SAUNDERS
Why quantum theory implies many worlds
It is argued that the unitary formalism of quantum theory, if applied to the entire universe, implies that the wave function has the structure of a system of dynamically decoupled evolutions (‘branches’), each of which is quasi-classical. Understood in descriptive terms, this structure implies, given relatively uncontentious assumptions of rationality (that have nothing to do with probability), that agents who respect those assumptions will treat the modulus squared amplitudes of those branches as they would objective probabilities. In this sense quantum theory *implies* many worlds.

17h15-17Hh45 : Discussion et conclusion

Séance sous la co-direction de Pierre Livet, membre du comité de pilotage de l’IMéRA, philosophe épistémologue (université de Provence), co-animateur du pôle Méditerranée de l’IMéRA, et de Sandro Vaienti, membre du comité de pilotage de l’IMéRA, mathématicien (université de Toulon et du Var), directeur de la Fédération de la Recherche des Unités de Mathématiques de Marseille (FRUMAM).

Intervenants :
Jean Bricmont, professeur de physique théorique à l'université catholique de Louvain dans l'unité de physique théorique et de physique mathématique (département de physique), et membre de l'Académie royale de Belgique,
Thomas Durt, physicien, professeur à l'Ecole Centrale Marseille, rattaché à l’Institut Fresnel,
Simon Saunders, professeur de philosophie de la physique à l'université d'Oxford et résident de l'IMéRA.

Accès sur inscription.