Hiding Lorentz Invariance Violation with MOND

TL;DR

This paper proposes a modification to Hořava gravity that hides Lorentz Invariance Violation in high-gradient regions, producing MOND-like behavior at low accelerations, potentially explaining galactic dynamics without detectable Lorentz violation.

Contribution

It introduces a simple low-energy modification to non-projectable Hořava gravity that effectively conceals Lorentz violation and reproduces MOND phenomenology at low accelerations.

Findings

Camouflages Lorentz violation in high-gradient regions

Reproduces MOND phenomenology at low accelerations

Suggests a way to hide Lorentz violation from current observations

Abstract

Ho\v{r}ava gravity is a attempt to construct a renormalizable theory of gravity by breaking the Lorentz Invariance of the gravitational action at high energies. The underlying principle is that Lorentz Invariance is an approximate symmetry and its violation by gravitational phenomena is somehow hidden to present limits of observational precision. Here I point out that a simple modification of the low energy limit of Ho\v{r}ava gravity in its non-projectable form can effectively camouflage the presence of a preferred frame in regions where the Newtonian gravitational field gradient is higher than $cH_0$; this modification results in the phenomenology of MOND at lower accelerations.