A Large N expansion for Gravity

TL;DR

This paper introduces a novel Large N expansion framework for gravity, utilizing a split of the Einstein-Hilbert action into a BF topological component and constraints, with implications for matter fields and holography.

Contribution

It presents a new Large N expansion scheme for gravity based on topological and constrained actions, connecting to holography and higher spin theories.

Findings

The scheme incorporates matter fields into the expansion.

It highlights the role of non-orientable fat graphs in matter interactions.

Connections to holography and higher spin fields are explored.

Abstract

A Large N expansion for gravity is proposed. The scheme is based on the splitting of the Einstein-Hilbert action into the BF topological action plus a constraint. The method also allows to include matter fields. The relation between matter and non orientable fat graphs in the expansion is stressed; the special role of scalars is shortly discussed. The connections with the Holographic Principle and higher spin fields are analyzed.