Density-metric unimodular gravity: vacuum maximal symmetry

TL;DR

This paper explores vacuum solutions in density-metric unimodular gravity, revealing significant differences from standard inflationary models, notably replacing exponential expansion with power-law behavior and excluding open universes with non-zero cosmological constants.

Contribution

It provides a detailed analysis of vacuum maximally symmetric solutions in a novel unimodular gravity framework, highlighting key deviations from conventional cosmological solutions.

Findings

De Sitter exponential expansion is replaced by power-law behavior.

Open universes with non-zero cosmological constant are not supported.

The theory predicts different vacuum symmetry solutions than standard models.

Abstract

We have investigated the vacuum maximally symmetric solutions of recently proposed density-metric unimodular gravity theory,the results are widely different from inflationary senario.The exponential dependence on time in deSitter space is substiuted by a power law. Open space-times with non-zero cosmological constant are excluded in this theory