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arXiv · 1901.09857

Unambiguous Phase Spaces for Subregions

Josh Kirklin
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Abstract

The covariant phase space technique is a powerful formalism for understanding the Hamiltonian description of covariant field theories. However, applications of this technique to problems involving subregions, such as the exterior of a black hole, have heretofore been plagued by boundary ambiguities. We provide a resolution of these ambiguities by directly computing the symplectic structure from the path integral, showing that it may be written as a contour integral around a partial Cauchy surface. This result has implications for gauge symmetry and entanglement.

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Josh Kirklin. 2019-01-28. Unambiguous Phase Spaces for Subregions. https://doi.org/10.1007/jhep03(2019)116

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