Spontaneous Symmetry Breaking and Landau Phase Transition in Horava Gravity

TL;DR

This paper explores how higher derivative terms in Horava gravity induce spontaneous symmetry breaking, leading to a phase transition that alters the vacuum structure and modifies gravitational potential at small scales.

Contribution

It demonstrates the emergence of a space-dependent vacuum and spontaneous translation symmetry breaking in Horava gravity due to higher derivative instabilities.

Findings

Higher derivative terms cause Minkowski ground state instability.

Spontaneous symmetry breaking results in a space-dependent vacuum metric.

Newtonian potential is modified at small length scales.

Abstract

Presence of higher derivative terms in the Horava model of gravity can generate an instability in the Minkowski ground state. This in turn leads to a space dependent vacuum metric with a length scale determined by the higher derivative coupling coefficient. The translation invariance is spontaneously broken in the process. The phenomenon is interpreted as a form of Landau liquid-solid phase translation. The (metric) condensate acts as a source that modifies the Newtonian potential below the length scale but keeps it unchanged for sufficiently large distance.