Static spheres — Sources of scalar,electromagnetic, and gravitational fields

Static sources of scalar, electromagnetic, and gravitational fields are considered within the theory of general relativity and within the class of scalar-tensor gravitation theories. From the conditions of regularity and nonnegativeness of matter density a number of limitations on the possible model parameters are obtained. An example of a regular model in general relativity is presented.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 51–56, October, 1977.