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arXiv · 1612.00278

Enhanced Asymptotic Symmetry Algebra of 2+1 Dimensional Flat Space

Stéphane Detournay·Max Riegler
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Abstract

In this paper we present a new set of asymptotic boundary conditions for Einstein gravity in 2+1 dimensions with vanishing cosmological constant that are a generalization of the Barnich-Comp{\`e}re boundary conditions gr-qc/0610130. These new boundary conditions lead to an asymptotic symmetry algebra that is generated by a $\mathfrak{bms}_3$ algebra and two affine $\hat{\mathfrak{u}}(1)$ current algebras. We then apply these boundary conditions to Topologically Massive Gravity (TMG) and determine how the presence of the gravitational Chern-Simons term affects the central extensions of the asymptotic symmetry algebra. We furthermore determine the thermal entropy of solutions obeying our new boundary conditions for both Einstein gravity and TMG.

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Stéphane Detournay, Max Riegler. 2016-12-01. Enhanced Asymptotic Symmetry Algebra of 2+1 Dimensional Flat Space. https://doi.org/10.1103/physrevd.95.046008

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