Unambiguos notion of total intrinsic angular momentum in general relativity

EMANUEL GALLO; OSVALDO M. MORESCHI

Varsovia

Conferencia; GR20, 20th International Conference on General Relativity; 2013

International Society on General Relativity and Gravitation

The notion of total angular momentum at future null infinity has been the subject of numerous works.Different author have employed a variety of approaches that yielded nonequivalent definitions.In the case of a spacetime with axial symmetry due to the conservation property of Komar integrals, it is tempting to use as the appropriate notion of totalangular momentum at future null infinity. But in a realistic situation the spacetimewill not have any symmetries and the problem remains.Almost all of the suggested definitions, for the general case, suffer from the so called problem of supertranslations. However one of the authors was able to providewith a definition of intrinsic angular momentum which have circumvented those problemsand also provided at the same time with the notion of center of mass at futurenull infinity. This approach was based on the notion of charge integrals of theRiemann tensor.In this work we present the most general notion of intrinsic angular momentum,based on charge integrals approach, that is suitable for radiating spacetimes and do notsuffer from supertranslations ambiguities.We also present the implications in requiring explicit agreement with theKomar integrals in the case of axial symmetry.