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Extrinsic Time in Quantum Cosmology

S. C. Beluardi·Rafael Ferraro
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Abstract

An extrinsic time is identified in most isotropic and homogeneous cosmological models by matching them with the ideal clock - a parametrized system whose only "degree of freedom" is time -. Once this matching is established, the cosmological models are quantized in the same way as the ideal clock. The space of solutions of the Wheeler-DeWitt equation is turned out into a Hilbert space by inserting a time dependent operator in the inner product, yielding a unitary theory equivalent to the phase space reduced theory.

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S. C. Beluardi, Rafael Ferraro. 1995-04-26. Extrinsic Time in Quantum Cosmology. https://doi.org/10.1103/physrevd.52.1963

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