Massive Gravity from Higher Derivative Gravity with Boundary Conditions

TL;DR

This paper demonstrates that a carefully parameterized higher derivative gravity theory on asymptotically de Sitter spacetime can yield a unitary, ghost-free massive gravity model in four dimensions, eliminating problematic modes.

Contribution

It introduces a novel framework for massive gravity derived from higher derivative gravity with specific boundary conditions, ensuring unitarity and absence of ghost modes.

Findings

Achieves a ghost-free massive gravity in four dimensions.

Eliminates the Boulware-Deser ghost mode.

Provides a consistent higher derivative gravity model with boundary conditions.

Abstract

With an appropriate choice of parameters, a higher derivative theory of gravity can describe a normal massive sector and a ghost massless sector. We show that, when defined on an asymptotically de Sitter spacetime with Dirichlet boundary conditions, such a higher derivative gravity can provide a framework for a unitary theory of massive gravity in four spacetime dimensions. The resulting theory is free not only of higher derivative ghosts but also of the Boulware-Deser mode.