Time asymmetric extensions of general relativity

Abstract

We describe a class of modified gravity theories that deform general relativity in a way that breaks time reversal invariance and, very mildly, locality. The algebra of constraints, local physical degrees of freedom, and their linearized equations of motion, are unchanged, yet observable effects may be present on cosmological scales, which have implications for the early history of the universe. This is achieved in the Hamiltonian framework, in a way that requires the constant mean curvature gauge conditions and is, hence, inspired by shape dynamics.

19 pages, LaTex, no figures

References in corpus (2)

• Einstein gravity as a 3D conformally invariant theory
• Conformal Superspace: the configuration space of general relativity

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• Reversing the irreversible: from limit cycles to emergent time symmetry
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