Tetrad symmetries
Let (M,g) be a parallelizable four-dimensional space-time. A parallelization \(z_ 1,z_ 2,z_ 3,z_ 4\in {\mathfrak X}(M)\) of M is called ``tetrad''. The main result of the paper is: if G is a subgroup of the group of motions of (M,g), then there exists a tetrad, symmetric under G iff the rank of the generators of G is equal to the order of G. An example of such a tetrad is also provided.
parallelizable four-dimensional space-time
scientific article; zbMATH DE number 4173827