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arXiv · 2504.11955

Revisiting Unimodular Quantum Cosmology

Júlio C. Fabris·Luiz Filipe Guimarães·Nelson Pinto-Neto·Mahamadou Hamani Daouda
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Abstract

The quantization of unimodular gravity in minisuperspace leads to a time evolution of states generated by the Hamiltonian, as in usual quantum mechanics. We revisit the analysis made in Ref. \cite{unruh}, extending it to phantom scalar fields. It is argued that only in this case a non-trivial evolution for the scalar field can be obtained. The behavior of the scale factor presents a bounce followed by a de Sitter expansion, reproducing the quantum cosmological scenario in General Relativity when the source is given by a cosmological term described by the Schutz variable. The analysis is extended to the Brans-Dicke scalar tensor theory.

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Júlio C. Fabris, Luiz Filipe Guimarães, Nelson Pinto-Neto, Mahamadou Hamani Daouda. 2025-04-16. Revisiting Unimodular Quantum Cosmology. https://arxiv.org/abs/2504.11955

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