Unimodular quantum cosmology in the connection representation: A minimal model

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Yamashita, Shinji
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914344065826816
author Yamashita, Shinji
author_facet Yamashita, Shinji
contents We present a quantization of unimodular gravity in the connection representation for a homogeneous, isotropic, and spatially flat cosmological model without matter. In this model, the wave function is governed by a Schrödinger-type equation derived from a reduced phase space approach. Our analysis suggests that, within this minimal setting, the regularity of the operators and the self-adjointness of the Hamiltonian operator are incompatible with a negative cosmological constant. For a positive cosmological constant, the wave functions vanish at zero spatial volume. This behavior emerges as a consequence of enforcing the unimodular condition at the quantum level. Semiclassical fluctuations of the geometry are evaluated and discussed in relation to the cosmological constant problem.
format Preprint
id arxiv_https___arxiv_org_abs_2602_19704
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Unimodular quantum cosmology in the connection representation: A minimal model
Yamashita, Shinji
General Relativity and Quantum Cosmology
We present a quantization of unimodular gravity in the connection representation for a homogeneous, isotropic, and spatially flat cosmological model without matter. In this model, the wave function is governed by a Schrödinger-type equation derived from a reduced phase space approach. Our analysis suggests that, within this minimal setting, the regularity of the operators and the self-adjointness of the Hamiltonian operator are incompatible with a negative cosmological constant. For a positive cosmological constant, the wave functions vanish at zero spatial volume. This behavior emerges as a consequence of enforcing the unimodular condition at the quantum level. Semiclassical fluctuations of the geometry are evaluated and discussed in relation to the cosmological constant problem.
title Unimodular quantum cosmology in the connection representation: A minimal model
topic General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2602.19704