B. Carter et al., AVOIDANCE OF COLLAPSE BY CIRCULAR CURRENT-CARRYING COSMIC-STRING LOOPS, Physical review. D. Particles and fields, 55(8), 1997, pp. 4647-4662
Earlier attempts to calculate the nonlinear dynamical evolution of Wit
ten-type superconducting vacuum vortex defects relied on the use of ap
proximate conducting string models that were too simple to take proper
account of the effect of current saturation. This effect is however a
llowed for adequately in a newly developed class of rather more compli
cated, though still conveniently analytic, conducting string models. T
hese more realistic models have recently been employed by Larsen and A
xenides for investigating the collapse of circular string loops in the
case for which angular momentum is absent. The present work extends t
his investigation to the generic case of circular string loops for whi
ch angular momentum is present, so that there will be a centrifugal po
tential barrier. This barrier will prevent collapse unless the initial
conditions are such that the relevant current saturation limit is att
ained, in which case the string description of the vortex defect will
break down, so that its subsequent fate is hard to foresee. On the oth
er hand if saturation is avoided one would expect that the loop will e
ventually radiate away its excess energy and settle down into a vorton
-type equilibrium state.