## Séminaire de Physique Théorique

**Logic is to the quantum as geometry is to gravity**

R. Sorkin, Perimeter institute, Canada

Thursday 02 July 2009 14:00 - Tours - Salle 1180 (Bât E2)

**Résumé :**

Abstract: I will rephrase the question, "What is a quantal reality?" as "What is a quantal history?" (the word history having here the same meaning as in the phrase sum-over-histories). The answer I will propose modifies the rules of logical inference in order to resolve a contradiction between the idea of reality as a single history and the principle that events of zero measure cannot happen (the Kochen-Specker paradox being a classic expression of this contradiction). The so-called measurement problem is then solved if macroscopic events satisfy classical logic, and this can in principle be decided by a calculation. The resulting conception of reality involves neither multiple worlds nor external observers. It is therefore suitable for quantum gravity in general and causal sets in particular.

**Liens :**