Einstein-Cartan pseudoscalaron inflation

TL;DR

This paper explores a cosmological inflation model based on Einstein-Cartan gravity, incorporating a pseudoscalar field called the pseudoscalaron, which arises from torsion and drives inflation with a complex post-inflationary evolution.

Contribution

It introduces a novel inflationary framework using Einstein-Cartan gravity with a pseudoscalaron field derived from torsion, linking higher derivative terms to early universe dynamics.

Findings

The pseudoscalaron potential enables a realistic inflationary phase.

The model predicts a rich post-inflationary epoch due to matter coupling.

The effective action combines General Relativity with a dynamic pseudoscalar field.

Abstract

We study a class of early universe cosmological models based on Einstein-Cartan gravity and including a higher derivative term corresponding to a power of the Holst scalar curvature. The resulting effective action is basically given by General Relativity and an additional neutral pseudoscalar field (the pseudoscalaron), unequivocally related to the corresponding components of the torsion, that necessarily acquire a dynamics. The induced pseudoscalaron potential provides a realistic inflationary phase together with a very rich postinflationary epoch, resulting by the coupling of the pseudoscalaron to ordinary matter.