Modern theoretical physics creates a mathematical, structural, "syntactic" model of the Universe. Clarifying the nature of mathematics suggests that the correspondence between the inner mental and external physical worlds is not limited only to their structural similarity, but can also be extended to the sphere of ontology. The assumption of the ontological similarity of the mathematician-creator of the mathematical universe to the external physical universe, existing in the psychic reality, allows us to outline the way to solve the “great” problems of modern physics, formulated by the Nobel Laureate, Academician V.L. Ginzburg.