Isotropic cosmologies in Weyl geometry

TL;DR

This paper investigates homogeneous and isotropic cosmologies within Weyl geometry, reducing the field equations to Einstein equations with a two-fluid source, analyzing their dynamics, and exploring the potential for late accelerated expansion.

Contribution

It demonstrates that Weyl 1-form effects do not generally lead to late acceleration in simple cosmological models, providing a dynamical systems analysis.

Findings

Weyl 1-form does not induce late acceleration in simple models

Field equations reduce to Einstein equations with a two-fluid source

Qualitative analysis of cosmological dynamics

Abstract

We study homogeneous and isotropic cosmologies in a Weyl spacetime. We show that for homogeneous and isotropic spacetimes, the field equations can be reduced to the Einstein equations with a two-fluid source. We write the equations as a two-dimensional dynamical system and analyze the qualitative, asymptotic behavior of the models. We examine the possibility that in certain theories the Weyl 1-form may give rise to a late accelerated expansion of the Universe and conclude that such behaviour is not met as a generic feature of the simplest cosmologies.