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On certain quasi-local spin-angular momentum expressions for large spheres near the null infinity

Laszlo B Szabados
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Abstract

The recently suggested quasi-local spin-angular momentum expressions, based on the Bramson superpotential and on the holomorphic or anti-holomorphic spinor fields, are calculated for large spheres near the future null infinity of asymptotically flat Einsten-Maxwell spacetimes. It is shown that although the expression based on the anti-holomorphic spinors is finite and unambiguously defined only in the center-of-mass frame (i.e. it diverges in general), the corresponding Pauli-Lubanski spin is always finite, free of ambiguities, and is built only from the gravitational data. Thus it defines a gravitational spin expression at the future null infinity. The construction based on the holomorphic spinors diverges in presence of outgoing gravitational radiation. For stationary spacetimes both constructions reduce to the `standard' expression.

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Laszlo B Szabados. 2001-09-13. On certain quasi-local spin-angular momentum expressions for large spheres near the null infinity. https://doi.org/10.1088/0264-9381%2F18%2F24%2F312

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