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arXiv · 2305.09735

BMS symmetry in gravity: Front form versus Instant form

Sudarshan Ananth·Sucheta Majumdar
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Abstract

In General Relativity, the allowed set of diffeomorphisms or gauge transformations at asymptotic infinity forms the BMS group, an infinite-dimensional extension of the Poincar\'e group. We focus on the structure of the BMS group in two distinct forms of Hamiltonian dynamics - the instant and front forms. Both similarities and differences in these two forms are examined while emphasising the role of non-covariant approaches to symmetries in gravity.

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Sudarshan Ananth, Sucheta Majumdar. 2023-05-16. BMS symmetry in gravity: Front form versus Instant form. https://doi.org/10.1142/s0218271823420014

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