Inflation and Reheating with a Fermionic Field

TL;DR

This paper explores a novel inflationary model where a fermionic field acts as the inflaton, analyzing its implications for inflation and reheating through non-minimal gravitational coupling.

Contribution

It introduces a fermion-based inflaton model with non-minimal coupling to gravity, expanding the scope beyond scalar field models.

Findings

Exponential expansion possible with fermion due to non-minimal coupling

Derived relations between coupling strength, mass, and Yukawa coupling

Provides a framework for fermionic reheating scenarios

Abstract

Inflation has long been the accepted paradigm for understanding the early universe. Most models of inflation have a scalar field acting as the inflaton particle which decays after inflation during a process called reheating into standard model (SM) particles. In this work, we consider a fermion as the inflaton field. Noether symmetry arguments show that an exponentially expanding universe is possible with a fermion if it is coupled non-minimally to gravity. We use such a scenario in this model to study both inflation and reheating. We find relations between the various parameters involved in this model which include the non-minimal coupling strength $\xi$, the mass $m$ and the Yukawa coupling $Y$.