Covariant Stückelberg analysis of de Rham-Gabadadze-Tolley massive gravity with a general fiducial metric
arXiv:1409.3074 · doi:10.1103/PhysRevD.90.124073
Abstract
The Stückelberg analysis of nonlinear massive gravity in the presence of a general fiducial metric is investigated. We develop a "covariant" formalism for the Stückelberg expansion by working with a local inertial frame, through which helicity modes can be characterized correctly. Within this covariant approach, an extended decoupling limit analysis can be consistently performed, which keeps fixed with the Riemann tensor of the fiducial metric. In this extended decoupling limit, the scalar mode acquires self-interactions due to the presence of the curvature of the fiducial metric. However, the equation of motion for remains of second order in derivatives, which extends the understanding of the absence of the Boulware Deser ghost in the case of a flat fiducial metric.
16 pages, 1 figure; v2 published version