Born-Infeld Gravity with a Unique Vacuum and a Massless Graviton

TL;DR

This paper develops an n-dimensional Born-Infeld gravity theory that maintains Einstein-like vacuum and graviton properties, offering a minimal, UV-improved extension of Einstein's gravity with potential quantum gravity applications.

Contribution

It constructs a Born-Infeld type gravity theory with a unique vacuum and a massless graviton, incorporating the Gauss-Bonnet term and exploring an infinite-dimensional limit leading to exponential gravity.

Findings

The theory has a unique maximally symmetric vacuum.

It supports a single massless spin-2 graviton.

In the infinite-dimensional limit, exponential gravity emerges.

Abstract

We construct an n-dimensional Born-Infeld type gravity theory that has the same properties as Einstein's gravity in terms of the vacuum and particle content: Namely, the theory has a unique viable vacuum (maximally symmetric solution) and a single massless unitary spin-2 graviton about this vacuum. The BI gravity, in some sense, is the most natural, minimal generalization of Einstein's gravity with a better UV behavior, and hence, is a potentially viable proposal for low energy quantum gravity. The Gauss-Bonnet combination plays a non-trivial role in the construction of the theory. As an extreme example, we consider the infinite dimensional limit where an interesting exponential gravity arises.