Gonchar's problems, symmetrization of condensers and new applications of dissymmetrization

Two problems of potential theory are discussed, the solution of which had a significant impact on the development of symmetrization methods in the theory of functions and related areas. The recent results obtained using dissymmetrization of condensers are presented. We give the precise estimates for the Green energy of a discrete charge in $n$-space and a sharp upper bound for the least critical values of finite Blaschke products.