Emergent quantum mechanics and emergent symmetries

Gerard ’t Hooft

Published Jan 1, 2007• 57 citations

Abstract

Quantum mechanics is ‘emergent’ if a statistical treatment of large scale phenomena in a locally deterministic theory requires the use of quantum operators. These quantum operators may allow for symmetry transformations that are not present in the underlying deterministic system. Such theories allow for a natural explanation of the existence of gauge equivalence classes (gauge orbits), including the equivalence classes generated by general coordinate transformations. Thus, local gauge symmetries and general coordinate invariance could be emergent symmetries, and this might lead to new alleys towards understanding the flatness problem of the Universe. Presented at the 13th International Symposium on Particles, Strings and Cosmology, PASCOS, Imperial College, London, July 6, 2007

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