Cosmological perturbations of massive gravity coupled to DBI Galileons

Abstract

Certain scalar fields with higher derivative interactions and novel classical and quantum mechanical properties - the Galileons - can be naturally covariantized by coupling to nonlinear massive gravity in such a way that their symmetries and number of degrees of freedom are unchanged. We study the propagating degrees of freedom in these models around cosmologically interesting backgrounds. We identify the conditions necessary for such a theory to remain ghost free, and consider when tachyonic instabilities can be avoided. We show that on the self-accelerating branch of solutions, the kinetic terms for the vector and scalar modes of the massive graviton vanish, as in the case of pure massive gravity.

9 pages. Invited for the Classical and Quantum Gravity focus issue on massive gravity. v3 mini-superspace expressions for the higher galileons corrected

References in corpus (9)

• Resummation of Massive Gravity
• Covariant Galileon
• Generalized Galileons: All scalar models whose curved background extensions maintain second-order field equations and stress tensors
• Multi-field galileons and higher co-dimension branes
• Self-accelerating Massive Gravity: Exact solutions for any isotropic matter distribution
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• General Embedded Brane Effective Field Theories
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• A Covariant Master Theory for Novel Galilean Invariant Models and Massive Gravity

Cited by in corpus (20)

• Beyond the Cosmological Standard Model
• Massive Gravity
• Cosmological Stability Bound in Massive Gravity and Bigravity
• Dynamical Analysis of an Integrable Cubic Galileon Cosmological Model
• Noether symmetries and stability of ideal gas solution in Galileon Cosmology
• Cosmological investigations of (extended) nonlinear massive gravity schemes with non-minimal coupling
• $F(R)$ nonlinear massive theories of gravity and their cosmological implications
• Stable FLRW solutions in Generalized Massive Gravity
• Cosmology of F(R) nonlinear massive gravity
• On the stability of Einstein static universe at background level in massive bigravity
• Cosmology in rotation-invariant massive gravity with non-trivial fiducial metric
• Cutoff for Extensions of Massive Gravity and Bi-Gravity
• Coupling between Galileon and massive gravity with composite metrics
• Extended DBI massive gravity with generalized fiducial metric
• Galileons Coupled to Massive Gravity: General Analysis and Cosmological Solutions
• Cosmology of Massive Gravity and its Extensions
• Derivative couplings in massive bigravity
• Cosmological model due to dimensional reduction of higher-dimensional massive gravity theory
• Cosmological evolutions of $F(R)$ nonlinear massive gravity
• On the flat spacetime Galileons and the Born-Infeld type structures