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arXiv · 2105.11623

Center-of-mass ambiguity for Bondi-Metzner-Sachs charges

Adam D. Helfer
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Abstract

Dray and Streubel proposed a definition of angular momentum in general relativity based on `Bondi-Metzner-Sachs (BMS) charges'. I show here that the natural definition of center of mass in this program has an infinite-dimensional ambiguity. (This seems not to have been noticed before because previous work has tacitly carried over a special-relativistic assumption.) A related point is that the natural definition of spin in this context is translation-, but not supertranslation-, invariant.

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Adam D. Helfer. 2021-05-25. Center-of-mass ambiguity for Bondi-Metzner-Sachs charges. https://doi.org/10.1088/1361-6382%2Fabfc2e

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