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arXiv · 1007.1563

New formulation of Horava-Lifshitz quantum gravity as a master constraint theory

Chopin Soo·Jinsong Yang·Hoi-Lai Yu
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Abstract

Both projectable and non-projectable versions of Horava-Lifshitz gravity face serious challenges. In the non-projectable version, the constraint algebra is seemingly inconsistent. The projectable version lacks a local Hamiltonian constraint, thus allowing for an extra scalar mode which can be problematic. A new formulation of non-projectable Horava-Lifshitz gravity, naturally realized as a representation of the master constraint algebra studied by loop quantum gravity researchers, is presented. This yields a consistent canonical theory with first class constraints. It captures the essence of Horava-Lifshitz gravity in retaining only spatial diffeomorphisms (instead of full space-time covariance) as the physically relevant non-trivial gauge symmetry; at the same time the local Hamiltonian constraint needed to eliminate the extra mode is equivalently enforced by the master constraint.

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Chopin Soo, Jinsong Yang, Hoi-Lai Yu. 2010-07-09. New formulation of Horava-Lifshitz quantum gravity as a master constraint theory. https://doi.org/10.1016/j.physletb.2011.05.055

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