Possible Nonlinear Completion of Massive Gravity

TL;DR

This paper proposes a nonlinear extension of massive gravity theories where a scalar ghost from the linear theory condenses, leading to positive-energy excitations, potentially resolving issues with earlier models.

Contribution

It introduces a novel nonlinear completion of massive gravity that addresses the ghost problem through scalar condensation, advancing theoretical understanding.

Findings

Scalar ghost condenses into positive-energy excitations

Provides a consistent nonlinear completion of massive gravity

Addresses stability issues in previous models

Abstract

Possible nonlinear completion of massive gravity is presented. An additional scalar ghost contained in linear theory condensates to give rise to positive-energy excitations.