Dilaton gravity (with a Gauss-Bonnet term) derived from five-dimensional Chern-Simons gravity

TL;DR

This paper derives a four-dimensional effective dilaton gravity theory with a Gauss-Bonnet term from five-dimensional Chern-Simons gravity, analyzing boundary conditions and matter coupling.

Contribution

It demonstrates how boundary conditions in five-dimensional Chern-Simons gravity lead to an effective four-dimensional dilaton gravity with a Gauss-Bonnet term, including matter interactions.

Findings

Effective boundary theory is dilaton gravity with Gauss-Bonnet term.

Boundary conditions determine the form of the effective theory.

Matter coupling is also incorporated into the boundary theory.

Abstract

We study the problem of boundary terms and boundary conditions for Chern-Simons gravity in five dimensions. We show that under reasonable boundary conditions one finds an effective field theory at the four-dimensional boundary described by dilaton gravity with a Gauss-Bonnet term. The coupling of matter is also discussed.