ON THE EMERGENT ASPECTS OF QUANTUM MECHANICS IN RELATION TO THE THERMODYNAMICS OF IRREVERSIBLE PROCESSES AND EMERGENT GRAVITY

Résumé

This PhD thesis elaborates on a proposal made by the Dutch theoretical physicist G. `t Hooft (1999 Nobel prize in physics), to the effect that quantum mechanics is the emergent theory of some underlying, deterministic theory. According to this proposal, information-loss effects in the underlying deterministic theory lead to the arrangement of states of the latter into equivalence classes, that one identifies as quantum states of the emergent quantum mechanics. In brief, quantisation is dissipation, according to `t Hooft. In our thesis we present two mechanisms whereby quantum mechanics is explicitly seen to emerge, thus explicitly realising `t Hooft`s proposal. The first mechanism makes use of Verlinde`s approach to classical mechanics and general relativity via holographic screens. This technique, first presented in 2010 in order to understand the emergent nature of spacetime and gravity, is applied in our thesis to the case of quantum mechanics. The second mechanism presented to support `t Hooft`s statement is based on a dictionary, also developed by the authors, between semiclassical quantum mechanics, on the one hand, and the classical theory of irreversible thermodynamics, on the other. This thermodynamical formalism, established by Nobel prize winners Onsager and Prigogine, can be easily mapped into that of semiclassical quantum mechanics.