Massive mimetic cosmology

Journal Article · 30 May 2019 · Physics Letters. B

DOI: https://doi.org/10.1016/j.physletb.2019.05.045 · OSTI ID:1547180

Solomon, Adam R.  ^[1]; Vardanyan, Valeri ^[2]; Akrami, Yashar  ^[3]

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1. Carnegie Mellon Univ., Pittsburgh, PA (United States)
2. Leiden Univ. (Netherlands)
3. Univ. Paris Sciences et Lettres (PSL) (France); Leiden Univ. (Netherlands)

We study the first cosmological implications of the mimetic theory of massive gravity recently proposed by Chamseddine and Mukhanov. This is a novel theory of ghost-free massive gravity which additionally contains a mimetic dark matter component. In an echo of other modified gravity theories, there are self-accelerating solutions which contain a ghost instability. In the ghost-free region of parameter space, the effect of the graviton mass on the cosmic expansion history amounts to an effective negative cosmological constant, a radiation component, and a negative curvature term. This allows us to place constraints on the model parameters—the graviton mass and the Stückelberg vacuum expectation value—by insisting that the effective radiation and curvature terms be within observational bounds. The late-time acceleration must be accounted for by a separate positive cosmological constant or other dark energy sector. We impose further constraints at the level of perturbations by demanding linear stability. We comment on the possibility of distinguishing this theory from ΛCDM with current and future large-scale structure surveys.

• Research Organization: Univ. of Arizona, Tucson, AZ (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: FG02-04ER41338; FG02-06ER41449
• OSTI ID: 1547180
• Alternate ID(s): OSTI ID: 1609535
• Journal Information: Physics Letters. B, Vol. 794, Issue C; ISSN 0370-2693
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English