Evolution of a system of closed cosmic strings

A system of closed cosmic strings is studied. I present a brief discussion of dynamics ofstrings. I find self intersections of a family of cosmic strings and investigate the distribution of daughter loops. A numerical model of evolution of a system of cosmic strings (low density gas of strings) is proposed and discussed. It is found that the energy spectrum of strings is not affected by the evolution and remains scale invariant. 15 refs., 6 figs. (author)