Bounce scenarios in the Sotiriou-Visser-Weinfurtner generalization of the projectable Horava-Lifshitz gravity

TL;DR

This paper analyzes bounce scenarios in a generalized Horava-Lifshitz gravity framework, comparing original and modified versions, focusing on their phase structures and the conditions for cosmological bounces.

Contribution

It introduces a comparison of phase structures in original and modified Horava-Lifshitz cosmology, highlighting the impact of additional terms on bounce solutions.

Findings

Both versions exhibit bouncing solutions under certain conditions.

Modified theory with relaxed detailed balance shows richer phase structure.

Negative dark radiation term influences bounce dynamics.

Abstract

The occurrence of a bounce in the FRW cosmology requires modifications of General Relativity. An example of such a modification is the recently proposed Horava-Lifshitz theory of gravity, which includes a "dark radiation" term with a negative coefficient in the analog of the Friedmann equation. A modification of the HL gravity, relaxing the "detailed balance" condition, brings additional terms to the equations of motion, corresponding to stiff matter. This paper presents comparison of the phase structure of the original and modified Horava cosmology. Special attention is paid to the analysis of a wide range of bouncing solution, appearing in both versions of the Horava theory.