Cosmic-string evolution

We summarize the results of high-resolution simulations of cosmic-string evolution in an expanding universe. The string network is found to relax to a scaling solution in accordance with Kibble's ``one-scale model.'' However, the long strings are found to have significant structure on scales much smaller than the scale length of the long-string network, and the size of the stable loops produced by the network is determined by this small-scale structure. This implies that the long strings rather than the loops will probably play a dominant role in the observational effects of cosmic strings.