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arXiv · 1611.03096

Gravity Degrees of Freedom on a Null Surface

Florian Hopfmüller·Laurent Freidel
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Abstract

A canonical analysis for general relativity is performed on a null surface without fixing the diffeomorphism gauge, and the canonical pairs of configuration and momentum variables are derived. Next to the well-known spin-2 pair, also spin-1 and spin-0 pairs are identified. The boundary action for a null boundary segment of spacetime is obtained, including terms on codimension two corners.

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Florian Hopfmüller, Laurent Freidel. 2016-11-09. Gravity Degrees of Freedom on a Null Surface. https://doi.org/10.1103/physrevd.95.104006

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