On plane wave solutions in Lorentz-violating extensions of gravity

TL;DR

This paper derives dispersion relations for plane wave solutions in Lorentz-violating gravity extensions across multiple dimensions, revealing the persistence of Lorentz-invariant modes even with higher derivatives involved.

Contribution

It provides a systematic derivation of dispersion relations in Lorentz-violating gravity models across various dimensions, highlighting the behavior of Lorentz-invariant modes.

Findings

Dispersion relations are obtained for dimensions 3, 4, 5, and 6.

Lorentz-invariant modes persist despite Lorentz violation.

Higher derivatives do not eliminate Lorentz-invariant solutions.

Abstract

In this paper, we obtain dispersion relations corresponding to plane wave solutions in various Lorentz-breaking extensions of gravity with dimensions 3, 4, 5 and 6. We demonstrate that these dispersion relations display an usual Lorentz-invariant mode when the corresponding additive term involves higher derivatives.