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Classical central extension for asymptotic symmetries at null infinity in three spacetime dimensions

Glenn Barnich·Geoffrey Compere
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Abstract

The symmetry algebra of asymptotically flat spacetimes at null infinity in three dimensions is the semi-direct sum of the infinitesimal diffeomorphisms on the circle with an abelian ideal of supertranslations. The associated charge algebra is shown to admit a non trivial classical central extension of Virasoro type closely related to that of the anti-de Sitter case.

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Glenn Barnich, Geoffrey Compere. 2009-02-23. Classical central extension for asymptotic symmetries at null infinity in three spacetime dimensions. https://doi.org/10.1088/0264-9381%2F24%2F5%2Ff01%2010.1088%2F0264-9381%2F24%2F11%2Fc01

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