Galileons from Lovelock actions

TL;DR

This paper shows how Galileon theories naturally emerge from higher-dimensional Lovelock gravity via Kaluza-Klein compactification, revealing new Galilean actions with second-order equations for fields and metric perturbations.

Contribution

It introduces a novel derivation of Galileon actions from Lovelock gravity using standard compactification, unifying higher-dimensional gravity with scalar field theories.

Findings

Galileon actions derived from Lovelock gravity in any dimension.

Uncovering of more general Galilean actions with second-order equations.

Purely second-order equations for Galileon and metric perturbations.

Abstract

We demonstrate how, for an arbitrary number of dimensions, the Galileon actions and their covariant generalizations can be obtained through a standard Kaluza-Klein compactification of higher-dimensional Lovelock gravity. In this setup, the dilaton takes on the role of the Galileon. In addition, such compactifications uncover other more general Galilean actions, producing purely second-order equations in the weak-field limit, now both for the Galileon and the metric perturbations.