Kaluza-Klein cosmology: The bulk metric
Kaluza-Klein cosmology: The bulk metric
The cosmological principle is applied to a five-dimensional vacuum manifold. The general (nontrivial) solution is explicitly given. The result is a unique metric, parametrized with the sign of the space curvature ($k=0,\ifmmode\pm\else\textpm\fi{}1$) and the signature of the fifth coordinate. Friedmann-Robertson-Walker (FRW) metrics can be obtained from this single ``mother'' metric …