Involutivity of field equations
arXiv:0902.1685 · doi:10.1063/1.3305321
Abstract
We prove involutivity of Einstein, Einstein-Maxwell and other field equations by calculating the Spencer cohomology of these systems. Relation with Cartan method is traced in details. Basic implications through Cartan-Kahler theory are derived.
13 pages; this version is updated with new field equations (radiation, dust etc) - they are proved involutive, Spencer cohomology calculated