Einstein-Cartan gravity with scalar-fermion interactions

TL;DR

This paper demonstrates that a single fermionic field within Einstein-Cartan gravity can produce accelerated cosmic expansion, providing an exact solution that mimics the cosmological constant's effects.

Contribution

It introduces an exact analytical solution to Einstein-Cartan-Dirac equations showing fermionic fields can drive accelerated expansion, a novel approach in this gravity framework.

Findings

Fermionic fields can cause accelerated expansion in Einstein-Cartan gravity

An exact solution describes universe expansion with w=-1

The solution parallels the ΛCDM model

Abstract

In this paper, we have considered the g-essence and its particular cases, k-essence and f-essence, within the framework of the Einstein-Cartan theory. We have shown that a single fermionic field can give rise to the accelerated expansion within the Einstein-Cartan theory. The exact analytical solution of the Einstein-Cartan-Dirac equations is found. This solution describes the accelerated expansion of the Universe with the equation of state parameter $w=-1$ as in the case of $\Lambda$CDM model.