A cosmological model in Weyl-Cartan spacetime

TL;DR

This paper proposes a cosmological model based on Weyl-Cartan spacetime, incorporating torsion and nonmetricity linked to vacuum polarization, and explores its implications for the early universe within metric-affine gravity.

Contribution

It introduces a novel cosmological model in Weyl-Cartan spacetime with torsion and nonmetricity proportional to vacuum polarization, extending previous work and connecting to metric-affine gravity.

Findings

Analysis of the cosmic scale factor evolution

Behavior of the Weyl 1-form in early universe

Integration of the model into metric-affine gravity framework

Abstract

We present a cosmological model for early stages of the universe on the basis of a Weyl-Cartan spacetime. In this model, torsion $T^{\alpha}$ and nonmetricity $Q_{\alpha \beta}$ are proportional to the vacuum polarization. Extending earlier work of one of us (RT), we discuss the behavior of the cosmic scale factor and the Weyl 1-form in detail. We show how our model fits into the more general framework of metric-affine gravity (MAG).