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arXiv · 2103.11253

Coadjoint representation of the BMS group on celestial Riemann surfaces

Glenn Barnich·Romain Ruzziconi
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Abstract

The coadjoint representation of the BMS group in four dimensions is constructed in a formulation that covers both the sphere and the punctured plane. The structure constants are worked out for different choices of bases. The conserved current algebra of non-radiative asymptotically flat spacetimes is explicitly interpreted in these terms.

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Glenn Barnich, Romain Ruzziconi. 2021-03-20. Coadjoint representation of the BMS group on celestial Riemann surfaces. https://doi.org/10.1007/jhep06(2021)079

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