Slow-roll inflation in $f(Q)$ non-metric gravity

TL;DR

This paper explores slow-roll inflation within $f(Q)$ non-metric gravity, analyzing potential and Hubble slow-roll approaches, and compares theoretical predictions with observational data from Planck and BICEP2/Keck.

Contribution

It introduces a detailed study of inflationary dynamics in $f(Q)$ gravity, including conformal transformations and observational constraints, which is a novel application in non-metric gravity theories.

Findings

Consistent inflationary models with observational data

Constraints on $f(Q)$ model parameters

Comparison of potential and Hubble slow-roll approaches

Abstract

We discuss the cosmological inflation in the context of $f(Q)$ non-metric gravity, where $Q$ is the non-metric scalar. After introducing conformal transformations for $f(Q)$ gravity, we first focus on the potential-slow-roll inflation by studying the corresponding potentials for different forms of the function $f(Q)$ in the Einstein frame. Secondly, we investigate the Hubble-slow-roll inflation for three classes of inflationary potentials considered for the specific form $f(Q)\propto Q^{2}$, in the Jordan frame. We compare results in both approaches with observations coming from Planck and BICEP2/Keck array satellites. Observational constraints on the parameters space of the models are obtained as well.