# Time and Evolution in Quantum and Classical Cosmology

@inproceedings{Kamenshchik2021TimeAE, title={Time and Evolution in Quantum and Classical Cosmology}, author={Alexander Yu. Kamenshchik and Jeinny Nallely P{\'e}rez Rodr{\'i}guez and Tereza Vardanyan}, year={2021} }

We analyze the issue of dynamical evolution and time in quantum cosmology. We emphasize the problem of choice of phase space variables that can play the role of a time parameter in such a way that for expectation values of quantum operators the classical evolution is reproduced. We show that it is neither necessary nor sufficient for the Poisson bracket between the time variable and the super-Hamiltonian to be equal to unity in all of the phase space. We also discuss the question of switching…

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