Birkhoff's theorem and perturbations in \(f(R)\) theories
Birkhoff's theorem states that under certain circumstances, spherically symmetric solutions of Einstein's field equation possess a fourth isometry. The present paper deals with the question, why an analogous theorem is not analogously valid in fourth-order gravity, especially in \(f(R)\) theories. Further it is discussed, whether in a perturbative sense, a partial validity can be found.
scientific article; zbMATH DE number 6069643
scientific article