Can neutrino viscosity drive the late time cosmic acceleration?

TL;DR

This paper demonstrates that neutrino bulk viscosity can cause the universe's late-time acceleration, mimicking dark energy effects without exotic components or modified gravity.

Contribution

It introduces a model where neutrino viscosity alone explains cosmic acceleration, avoiding the need for dark energy or gravity modifications.

Findings

Neutrino viscosity can produce negative deceleration parameters.

Certain models mimic the standard ΛCDM cosmology.

No exotic dark energy or gravity modifications are needed.

Abstract

In this paper it has been shown that the neutrino bulk viscous stresses can give rise to the late time acceleration of the universe. It is found that a number of spatially flat FRW models with a negative deceleration parameter can be constructed using neutrino viscosity and one of them mimics a $\Lambda$CDM model. This does not require any exotic dark energy component or any modification of gravity.