Expansion of the Universe in the case of the generalized Friedmann–Lemaitre–Robertson–Walker metric

In classical works, the equations for gravitational and electromagnetic fields are presented without deriving the right-hand sides. In this paper we provide a derivation of the right-hand sides and analyze the Milne–McCrea and Friedman models. In the case of the Friedman metric, it is possible to describe the accelerated expansion of the Universe with simple equations. The fact of accelerated expansion imposes a sign on the curvature: the curvature is negative, and our Universe is a Lobachevsky space.