His primary scientific contribution lies in the development of quantum physics, although he also contributed significantly to the fields of mechanics, theoretical optics, theory of gravitation, physics of continuous medium. In 1926 he generalized the Klein-Gordon equation. He gave his name to Fock space, the Fock representation and Fock state, and developed the Hartree-Fock method in 1930. He made many subsequent scientific contributions, during the rest of his life.
Historians of science, such as Loren Graham, see Fock as a representative and proponent of Einstein's theory of relativity within the Soviet world. At a time when most Marxist philosophers objected to relativity theory, Fock emphasized a materialistic understanding of relativity that coincided philosophically with Marxism.
Graham, L. (1982). "The reception of Einstein's ideas: Two examples from contrasting political cultures." In Holton, G. and Elkana, Y. (Eds.) Albert Einstein: Historical and cultural perspectives. Princeton, NJ: Princeton UP, pp. 107-136