On some global problems in the tetrad approach to quasi-local quantities

dc.creatorSzabados, Laszlo B
dc.date2007-12-01
dc.date2008-08-06
dc.date.accessioned2026-07-07T11:54:29Z
dc.date.available2026-07-07T11:54:29Z
dc.descriptionThe potential global topological obstructions to the tetrad approach to finding the quasi-local conserved quantities, associated with closed, orientable spacelike 2-surfaces S, are investigated. First we show that the Lorentz frame bundle is always globally trivializable over an open neighbourhood U of any such S if an open neighbourhood of S is space and time orientable, and hence a globally trivializable SL(2,C) spin frame bundle can also be introduced over U. Then it is shown that all the spin frames belonging to the same spinor structure on S have always the same homotopy class. On the other hand, on a 2-surface with genus g, there are $2^{2g}$ homotopically different Lorentz frame fields, and there is a natural one-to-one correspondence between these homotopy classes and the different SL(2,C) spinor structures.
dc.description13 pages, a more detailed discussion of the problems is given, Theorems 3.1 and 3.2 are modified slightly, the proof of Theorem 4.3 is improved, 5 references are added, misprints are corrected. Appearing in Class. Quantum Grav
dc.identifierhttps://arxiv.org/abs/0712.0085
dc.identifierhttp://arxiv.org/abs/0712.0085
dc.identifierClass.Quant.Grav.25:195004,2008
dc.identifierdoi:10.1088/0264-9381/25/19/195004
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/204914
dc.subjectGeneral Relativity and Quantum Cosmology
dc.titleOn some global problems in the tetrad approach to quasi-local quantities
dc.typetext

Files

Collections