EVOLUTION OF A STRING NETWORK IN BACKGROUNDS WITH ROLLING HORIZONS

Abstract

We discuss the temporal variation of the equation of state of a classical string network, evolving in a background in which the Hubble radius 1/H shrinks to a minimum and then re-expands to infinity. We also present a method to look for self-consistent non-vacuum string backgrounds, correponding to the simultaneous solution of the gravi-dilaton backgrounds equations and of the string equations of motion.

19 pages, plain tex, no figures, to appear in "String gravity and physics at the Planck energy scale" (World Scientific, Singapore, 1995)