Exact Solutions of Einstein’s Equations in the Presence of a Scalar Field

We review a class of exact solutions of Einstein’s equations in the presence of a scalar field that has three free parameters and become Janis–Newman–Winicour (JNW) metric and γ metric in a certain limit of parameters [1]. We also explain the rotating form of the class of axially symmetric metrics, which contain the rotating gamma and JNW metrics and the Bogush–Gal’tsov (BG) metric at certain values of the parameters [2].