On the equilibrium of charged masses in general relativity: the electrostatic case

The problem of the equilibrium of charged aligned masses is discussed within the framework of the electrostatic multi-soliton solution of the Einstein-Maxwell equations. The equilibrium states in a charged two-body system are considered in detail. We demonstrate the validity of Smarr's mass formula for a charged static black hole when the latter is in electrostatic equilibrium with a superextreme object.