On the Correspondence between Exact Solutions in Kaluza–Klein Theory and in Scalar–Tensor Theories

Abstract

Using the formal equivalences between Kaluza–Klein gravity, Brans–Dicke theory and general relativity coupled to a massless scalar field, exact solutions obtained in one theory will correspond to analogous solutions in the other two theories. Often exact solutions in one theory are "rediscovered" since theory are not recognized as analogs of the corresponding solutions in one of the other theories. We review here a number of exact solutions in each of the theories, with an emphasis on identifying and presenting the higher-dimensional version of the solutions. We also briefly comment upon the formal equivalence between Kaluza–Klein theory and scalar–tensor theories in general.