Scale Invariant Power Spectrum in Ho\v{r}ava-Lifshitz Cosmology without Matter

TL;DR

This paper shows that in Horava-Lifshitz cosmology, a scale-invariant power spectrum can be generated without matter, potentially offering an alternative to inflation by relying on the scalar mode in the UV regime.

Contribution

It demonstrates that relaxing the detailed balance condition in Horava-Lifshitz gravity allows the scalar mode to produce a scale-invariant spectrum, challenging the need for inflation.

Findings

Scalar mode can generate scale-invariant spectrum in UV era

Horava-Lifshitz cosmology may seed large scale structure

Alternative to inflation without matter

Abstract

In this paper we investigate the physical implications of the dynamical scalar mode in pure Horava-Lifshitz gravity on cosmology. We find that it can produce a scale-invariant power spectrum in UV era if the detailed balance condition on the action is relaxed. This indicates that the physical scalar mode may seed the large scale structure and Horava-Lifshitz cosmology could be a qualified alternative to inflationary scenario.