arXiv:2503.10752 · Journal of Physics Conference Series

Origin of time and probability in quantum cosmology

Leonardo Chataignier, Claus Kiefer, Mritunjay Tyagi

Published Jun 1, 2025• 3 citations

Abstract

Abstract We discuss how the classical notions of time and causal structure may emerge together with quantum-mechanical probabilities from a universal quantum state. For this, the process of decoherence between semiclassical branches is important. Our discussion is based on quantum geometrodynamics, a canonical approach to quantum gravity. In this framework, a particular boundary condition may illuminate the issue of the arrow of (classical) time in connection to the growth of entanglement entropy.

DOI: 10.1088/1742-6596/3017/1/012007

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