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Initial conditions and unitarity in unimodular quantum cosmology

Alan Daughton·Jorma Louko·Rafael D. Sorkin
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Abstract

We consider quantization of the positive curvature Friedmann cosmology in the unimodular modification of Einstein's theory, in which the spacetime four-volume appears as an explicit time variable. The Hamiltonian admits self-adjoint extensions that give unitary evolution in the Hilbert space associated with the Schrödinger equation. The semiclassical estimate to the no-boundary wave function of Hartle and Hawking is found. If this estimate is accurate, there is a continuous flux of probability into the configuration space from vanishing three-volume, and the no-boundary wave function evolves nonunitarily. Generalizations of these results hold in a class of anisotropic cosmologies. (Talk given at the 5th Canadian Conference on General Relativity and Relativistic Astrophysics, Waterloo, Ontario, Canada, May 1993.)

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Alan Daughton, Jorma Louko, Rafael D. Sorkin. 1993-05-18. Initial conditions and unitarity in unimodular quantum cosmology. https://arxiv.org/abs/gr-qc/9305016

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