Unifying inflation with dark energy in modified F(R) Horava-Lifshitz gravity

TL;DR

This paper explores a modified F(R) Horava-Lifshitz gravity model that unifies early inflation and late-time acceleration, analyzing its cosmological dynamics, singularities, and ways to resolve them.

Contribution

It introduces a non-linear modified F(R) Horava-Lifshitz gravity model that unifies inflation and dark energy, and investigates its singularities and potential cures.

Findings

Unified description of inflation and dark energy possible

Finite-time singularities can be cured with higher-derivative terms

Cosmological dynamics differ from standard F(R) models but can coincide for specific parameters

Abstract

We study FRW cosmology for a non-linear modified F(R) Horava-Lifshitz gravity which has a viable convenient counterpart. A unified description of early-time inflation and late-time acceleration is possible in this theory, but the cosmological dynamic details are generically different from the ones of the convenient viable F(R) model. Remarkably, for some specific choice of parameters they do coincide. The emergence of finite-time future singularities is investigated in detail. It is shown that these singularities can be cured by adding an extra, higher-derivative term, which turns out to be qualitatively different when compared with the corresponding one of the convenient F(R) theory.