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arXiv · 1408.2228

Asymptotic symmetries and subleading soft graviton theorem

Miguel Campiglia·Alok Laddha
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Abstract

Motivated by the equivalence between soft graviton theorem and Ward identities for the supertranslation symmetries belonging to the BMS group, we propose a new extension (different from the so-called extended BMS) of the BMS group which is a semi-direct product of supertranslations and Diff(S^2). We propose a definition for the canonical generators associated to the smooth diffeomorphisms and show that the resulting Ward identities are equivalent to the subleading soft graviton theorem of Cachazo and Strominger.

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Miguel Campiglia, Alok Laddha. 2014-12-17. Asymptotic symmetries and subleading soft graviton theorem. https://doi.org/10.1103/physrevd.90.124028

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