COMPUTER-SIMULATIONS OF THE MOTION AND DECAY OF GLOBAL STRINGS

Computer simulations have been carried out of the motion and decay of global strings, including spectrum analysis of the energy stored in the scalar field which describes the global string and the radiated Nambu-Goldstone bosons. We simulated relaxing pieces of bent string and collapsing circular loops. We find, for the string sizes investigated, that the spectrum of field energy hardens rather than softens while the string decays into Nambu-Goldstone radiation. We argue on theoretical grounds that this is indeed the most plausible general behaviour.