Cosmological scenarios in modified gravity with non-dynamical fields

TL;DR

This paper investigates various cosmological scenarios within modified Einstein gravity incorporating non-dynamical fields, highlighting a controlling parameter and exploring phenomena like inflation, dark energy, and potential solutions to the cosmological constant problem.

Contribution

It introduces a framework where auxiliary fields control cosmological regimes and discusses a novel self-tuning mechanism for the cosmological constant.

Findings

All cosmological scenarios are governed by a specific auxiliary field parameter.

Emergence of inflationary, radiation, matter, and dark energy dominated regimes.

Potential self-tuning solution to the cosmological constant problem during radiation era.

Abstract

In this paper we address the issue of exploring some cosmological scenarios in modified Einstein gravity through non-dynamical (auxiliary) fields. We found that all scenarios are controlled by a specific parameter associated with an auxiliary field. We explore the emergence of inflationary, radiation, matter and dark energy dominated regimes. Furthermore, an interesting possibility such as the emergence of a self-tuning mechanism to the cosmological constant problem in the radiation dominated era is also discussed.