Many Faces of Mimetic Gravity

Abstract

We consider the recently introduced mimetic gravity, which is a Weyl-symmetric extension of the General Relativity and which can play a role of an imperfect fluid-like Dark Matter with a small sound speed. In this paper we discuss in details how this higher- derivative scalar-tensor theory goes beyond the construction by Horndeski, keeping only one scalar degree of freedom on top of two standard graviton polarizations. In particular, we consider representations of the theory in different sets of Weyl-invariant variables and connect this framework to the singular Brans-Dicke theory. Further, we find solution of equations of motion for the mimetic gravity in the synchronous reference frame in a general curved spacetime. This solution is exact in the test-field approximation or in the case of a shear-free spacetime without any other matter.

10 pages, no figures

References in corpus (7)

• Quantum Gravity at a Lifshitz Point
• Healthy theories beyond Horndeski
• Exploring gravitational theories beyond Horndeski
• Mimetic $F(R)$ gravity: inflation, dark energy and bounce
• Dark energy, inflation and dark matter from modified F(R) gravity
• Quanta of Geometry: Noncommutative Aspects
• The scalar Einstein-aether theory

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