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arXiv · 2305.05436

Asymptotic symmetry algebra of Einstein gravity and Lorentz generators

Oscar Fuentealba·Marc Henneaux·Cédric Troessaert
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Abstract

The asymptotic symmetry algebra of four-dimensional Einstein gravity in the asymptotically flat context has been shown recently to be the direct sum of the Poincar\'e algebra and of an infinite-dimensional abelian algebra (with central charge) that includes the Bondi-Metzner-Sachs supertranslations. This result, obtained within the Hamiltonian formalism, yields a supertranslation invariant definition of the Lorentz generators (angular momentum and boosts). Definitions of Lorentz generators free from the ``supertranslation ambiguities'' have also been proposed recently at null infinity. We prove the equivalence of the two approaches for redefining the charges.

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Oscar Fuentealba, Marc Henneaux, Cédric Troessaert. 2023-05-09. Asymptotic symmetry algebra of Einstein gravity and Lorentz generators. https://arxiv.org/abs/2305.05436

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