Revisiting Unimodular Quantum Cosmology
Published: Apr 16, 2025
Last Updated: Apr 16, 2025
Authors:Júlio C. Fabris, Luiz Filipe Guimarães, Nelson Pinto-Neto, Mahamadou Hamani Daouda
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.