Massive Gravity in Three Dimensions

TL;DR

This paper introduces a higher-derivative extension of gravity in three dimensions that describes massive spin-2 fields, unifying topologically-massive gravity and supergravity extensions, with potential anti-de Sitter vacua.

Contribution

It develops a new higher-derivative gravity model in three dimensions that propagates massive spin-2 modes and extends to supergravity and cosmological contexts.

Findings

Equivalent to Pauli-Fierz at linearized level

Propagates two helicity states with different masses

Admits anti-de Sitter vacuum

Abstract

A particular higher-derivative extension of the Einstein-Hilbert action in three spacetime dimensions is shown to be equivalent at the linearized level to the (unitary) Pauli-Fierz action for a massive spin-2 field. A more general model, which also includes `topologically-massive' gravity as a special case, propagates the two spin 2 helicity states with different masses. We discuss the extension to massive ${\cal N}$-extended supergravity, and we present a `cosmological' extension that admits an anti-de Sitter vacuum.