Selfdual 2-form formulation of gravity and classification of energy-momentum tensors
arXiv:gr-qc/9504023 · doi:10.1088/0264-9381/13/8/020
Abstract
It is shown how the different irreducibility classes of the energy-momentum tensor allow for a Lagrangian formulation of the gravity-matter system using a selfdual 2-form as a basic variable. It is pointed out what kind of difficulties arise when attempting to construct a pure spin-connection formulation of the gravity-matter system. Ambiguities in the formulation especially concerning the need for constraints are clarified.
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