Cosmological models in Weyl geometrical scalar-tensor theory

TL;DR

This paper explores cosmological models within a Weyl geometrical scalar-tensor gravity framework, incorporating scalar potentials, revealing solutions that suggest geometric phase transitions and geometric-driven early universe acceleration.

Contribution

It extends previous Weyl scalar-tensor theories by including scalar potentials and analyzes resulting cosmological solutions, highlighting geometric phase transitions and early universe acceleration.

Findings

Solutions indicate possible geometric phase transitions.

Early universe acceleration can be driven purely by geometry.

Theoretical models suggest new cosmological scenarios.

Abstract

We investigate cosmological models in a recently proposed geometrical theory of gravity, in which the scalar field appears as part of the space-time geometry. We extend the previous theory to include a scalar potential in the action. We solve the vacuum field equations for different choices of the scalar potential and give a detailed analysis of the solutions. We show that in some cases a cosmological scenario is found that seems to suggest the appearance of a geometric phase transition. We build a toy model, in which the accelerated expansion of the early universe is driven by pure geometry.