Diophantine representation of enumerable predicates

This paper is the author's abstract of dissertation in partial fulfillment of the requirements for the degree of Doctor of Physicomathematical Sciences. The dissertation was defended on February 24, 1972 at a session of the faculty council of the V. A. Steklov Mathematics Institute, Academy of Sciences of the SSSR. The official opponents were: Doctor of Physicomathematical Sciences S. I. Adyan; Corresponding Member of the Academy of Sciences of the USSR Yu. L. Ershov; and Corresponding Member of the Academy of Sciences of the USSR D. K. Faddeev.