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arXiv · 1608.05088

The Dynamics of Supertranslations and Superrotations in 2+1 Dimensions

S. Carlip
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Abstract

Supertranslations, and at least in 2+1 dimensions superrotations, are asymptotic symmetries of the metric in asymptotically flat spacetimes. They are not, however, symmetries of the boundary term of the Einstein-Hilbert action, which therefore induces an action for the Goldstone-like fields that parametrize these symmetries. I show that in 2+1 dimensions, this action is closely related to a chiral Liouville action, as well as the "Schwarzian" action that appears in two-dimensional near-AdS physics.

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S. Carlip. 2016-08-17. The Dynamics of Supertranslations and Superrotations in 2+1 Dimensions. https://arxiv.org/abs/1608.05088

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