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arXiv · 1304.0449

Cosmological Perturbations in Extended Massive Gravity

A. Emir Gumrukcuoglu·Kurt Hinterbichler·Chunshan Lin·Shinji Mukohyama·Mark Trodden
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Abstract

We study cosmological perturbations around self-accelerating solutions to two extensions of nonlinear massive gravity: the quasi-dilaton theory and the mass-varying theory. We examine stability of the cosmological solutions, and the extent to which the vanishing of the kinetic terms for scalar and vector perturbations of self-accelerating solutions in massive gravity is generic when the theory is extended. We find that these kinetic terms are in general non-vanishing in both extensions, though there are constraints on the parameters and background evolution from demanding that they have the correct sign. In particular, the self-accelerating solutions of the quasi-dilaton theory are always unstable to scalar perturbations with wavelength shorter than the Hubble length.

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A. Emir Gumrukcuoglu, Kurt Hinterbichler, Chunshan Lin, Shinji Mukohyama, Mark Trodden. 2013-04-01. Cosmological Perturbations in Extended Massive Gravity. https://doi.org/10.1103/physrevd.88.024023

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