The generalized reduced modulus in spatial problems of the capacitorial tomography

The external problem of the spatial capacitorial tomography is considered. The notion of capacitorial defect of an object (a compact set) along Möbius directions in the space has been introduced. The criteria for the capacitorial invisibility of an object along the Möbius direction determined by a pair of points in the accessible region of the space has been obtained. The problem of upper estimates for the capacitorial defect along Möbius directions in the space, as well as it's connection with the notion of generalized reduced modulus by V.N. Dubinin, is there also considered in this paper.