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arXiv · 0909.2617

Symmetries of asymptotically flat 4 dimensional spacetimes at null infinity revisited

Glenn Barnich·Cedric Troessaert
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Abstract

It is argued that the symmetry algebra of asymptotically flat spacetimes at null infinity in 4 dimensions should be taken as the semi-direct sum of supertranslations with infinitesimal local conformal transformations and not, as usually done, with the Lorentz algebra. As a consequence, two dimensional conformal field theory techniques will play as fundamental a role in this context of direct physical interest as they do in three dimensional anti-de Sitter gravity.

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Glenn Barnich, Cedric Troessaert. 2010-01-10. Symmetries of asymptotically flat 4 dimensional spacetimes at null infinity revisited. https://doi.org/10.1103/physrevlett.105.111103

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