Cosmology of bigravity with doubly coupled matter
arXiv:1501.00864 · doi:10.1088/1475-7516/2015/04/026
Abstract
We study cosmology in the bigravity formulation of the dRGT model where matter couples to both metrics. At linear order in perturbation theory two mass scales emerge: an hard one from the dRGT potential, and an environmental dependent one from the coupling of bigravity with matter. At early time, the dynamics is dictated by the second mass scale which is of order of the Hubble scale. The set of gauge invariant perturbations that couples to matter follow closely the same behaviour as in GR. The remaining perturbations show no issue in the scalar sector, while problems arise in the tensor and vector sectors. During radiation domination, a tensor mode grows power-like at super-horizon scales. More dangerously, the only propagating vector mode features an exponential instability on sub-horizon scales. We discuss the consequences of such instabilities and speculate on possible ways to deal with them.
20 pages, 1 figure, references added
References in corpus (44)
- Modified Gravity and Cosmology
- Resummation of Massive Gravity
- Beyond the Cosmological Standard Model
- Massive Gravity
- Bimetric Gravity from Ghost-free Massive Gravity
- Resolving the Ghost Problem in non-Linear Massive Gravity
- On Non-Linear Actions for Massive Gravity
- Generalization of the Proca Action
- Massive Cosmologies
- Phases of massive gravity
- Massive gravity: nonlinear instability of the homogeneous and isotropic universe
- Cosmic Acceleration from Abelian Symmetry Breaking
- Open FRW universes and self-acceleration from nonlinear massive gravity
- Cosmological Solutions in Bimetric Gravity and their Observational Tests
- Accelerated expansion from ghost-free bigravity: a statistical analysis with improved generality
- FRW Cosmology in Ghost Free Massive Gravity
- Perturbations in Massive Gravity Cosmology
- Effective Lagrangians and Universality Classes of Nonlinear Bigravity
- On couplings to matter in massive (bi-)gravity
- Some remarks on the notions of general covariance and background independence
- Stable and unstable cosmological models in bimetric massive gravity
- Ghosts & Matter Couplings in Massive (bi-&multi-)Gravity
- Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV
- Nonlinear stability of cosmological solutions in massive gravity
- Lorentz-violating graviton masses: getting around ghosts, low strong coupling scale and VDVZ discontinuity
- Spherically Symmetric Solutions in Ghost-Free Massive Gravity
- Spontaneous Lorentz Breaking and Massive Gravity
- Degrees of Freedom in Massive Gravity
- Gravitational waves in bigravity cosmology
- FRW Cosmological Perturbations in Massive Bigravity
- The coupling to matter in Massive, Bi- and Multi-Gravity
- Restoring General Relativity in massive bi-gravity theory
- Cosmic expansion histories in massive bigravity with symmetric matter coupling
- The Cosmology of Interacting Spin-2 Fields
- Appearance of Boulware-Deser ghost in bigravity with doubly coupled matter
- Linear growth of structure in massive bigravity
- Massive gravity: a General Analysis
- Cosmological perturbations in massive gravity with doubly coupled matter
- Stability of the Self-accelerating Universe in Massive Gravity
- Cosmology in General Massive Gravity Theories
- Jet Substructure by Accident
- Cosmology in rotation-invariant massive gravity with non-trivial fiducial metric
- Lobotomy of Flux Compactifications
- Interactions of Charged Spin-2 Fields
Cited by in corpus (40)
- Cosmological Tests of Modified Gravity
- Beyond CDM: Problems, solutions, and the road ahead
- A systematic approach to generalisations of General Relativity and their cosmological implications
- Bimetric gravity is cosmologically viable
- Astrophysical Probes of the Vainshtein Mechanism: Stars and Galaxies
- Gravitational waves in bigravity cosmology
- Cosmology in bimetric theory with an effective composite coupling to matter
- Higuchi Ghosts and Gradient Instabilities in Bimetric Gravity
- Vielbein to the Rescue?
- Neutron star merger GW170817 strongly constrains doubly coupled bigravity
- A Note on Ghost-Free Matter Couplings in Massive Gravity and Multi-Gravity
- Cosmological gravitational particle production of massive spin-2 particles
- Dipolar Dark Matter with Massive Bigravity
- A general mass term for bigravity
- On stars, galaxies and black holes in massive bigravity
- On the uniqueness of the non-minimal matter coupling in massive gravity and bigravity
- Stability of the Early Universe in Bigravity Theory
- Scalar instabilities in bimetric gravity: The Vainshtein mechanism and structure formation
- Non-minimal derivative couplings of the composite metric
- New massive bigravity cosmologies with double matter coupling
- Surfing gravitational waves: can bigravity survive growing tensor modes?
- Consistent metric combinations in cosmology of massive bigravity
- Bimetric-Affine Quadratic Gravity
- Long Range Effects in Gravity Theories with Vainshtein Screening
- A general theory of linear cosmological perturbations: bimetric theories
- Cutoff for Extensions of Massive Gravity and Bi-Gravity
- Generalised matter couplings in massive bigravity
- Stable Cosmology in Generalised Massive Gravity
- Gravitational Waves in Doubly Coupled Bigravity
- Cosmological histories in bimetric gravity: A graphical approach
- On the viability of bigravity cosmology
- Cosmology of Massive Gravity and its Extensions
- Ghost-free completion of an effective matter coupling in bimetric theory
- Perturbations of Cosmological and Black Hole Solutions in Massive gravity and Bi-gravity
- Dark Energy and Doubly Coupled Bigravity
- Hamiltonian cosmology in bigravity and massive gravity
- Self-acceleration in scalar-bimetric theories
- Gravitational wave propagation beyond general relativity: waveform distortions and echoes
- Doubly coupled matter fields in massive bigravity
- Polarized solitons in higher-spin wave dark matter