2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/34759The classical problem of self-energy divergence was studied in the framework of Lagrangian formulation of Relativistic Mechanics. The conclusion was made that a revision of mass-energy concept is needed for the development of singularity-free gravitational and electromagnetic field theory. Perspectives of the development of unified field theory are discussed.General Relativity and Quantum Cosmologytext