Massive graviton from diffeomorphism invariance

TL;DR

This paper proposes a mechanism where the graviton gains mass through the functional measure without breaking diffeomorphism invariance, avoiding common problems of massive gravity.

Contribution

It introduces a novel quantum-level mass generation mechanism for the graviton that preserves gauge symmetry and avoids known issues like ghosts and discontinuities.

Findings

Graviton acquires mass without St"uckelberg fields

No violation of diffeomorphism invariance occurs

Avoids Boulware-Deser ghosts and vDVZ discontinuity

Abstract

We describe a mechanism in which the graviton acquires a mass from the functional measure without violating the diffeomorphism symmetry nor including St\"uckelberg fields. Since gauge invariance is not violated, the number of degrees of freedom goes as in general relativity. For the same reason, Boulware-Deser ghosts and the vDVZ disconinuity do not show up. The graviton thus becomes massive at the quantum level while avoiding the usual issues of massive gravity.