Is Quantum Mechanics a Probabilistic Theory?

Jiří Souček

Quantum Mechanics (QM) is primarily a probabilistic theory. The standard Kolmogorov probability theory is not suitable for this goal since it does not offer the possibility of the reversible time evolution. This implies the need to construct a new probability theory which is able to model the reversible time evolution. I have proposed such an Extended probability theory. The main goal of this project is to understand what QM is. In this note I shall describe the program of the research which is already partially realized.

Richard Healey

Itamar Pitowsky

Matthias Kleinmann, Tobias J. Osborne, Volkher B. Scholz +1 more

What singles out quantum mechanics as the fundamental theory of nature? Here we study local measurements in generalized probabilistic theories (GPTs) and investigate how observational limitations affect the production of correlations. We find that if only a subset of typical local measurements can be made then all the bipartite correlations produced in a GPT can be simulated to a high degree of accuracy by quantum mechanics. Our result makes use of a generalization of Dvoretzky's theorem for GPTs. The tripartite correlations can go beyond those exhibited by quantum mechanics, however.

Saul Youssef

Peter J. Lewis

A major problem facing no-collapse interpretations of quantum mechanics in the tradition of Everett is how to understand the probabilistic axiom of quantum mechanics (the Born rule) in the context of a deterministic theory in which every outcome of a measurement occurs. Deutsch claims to derive a decision-theoretic analogue of the Born rule from the non-probabilistic part of quantum mechanics and some non-probabilistic axioms of classical decision theory, and hence concludes that no probabilistic axiom is needed. I argue that Deutsch’s derivation begs the question.