Kinky Vortons

Abstract

Cosmic vortons are closed loops of superconducting cosmic strings carrying current and charge. Despite a large number of studies the existence and stability of cosmic vorton solutions is still an open problem. Numerical simulations of the nonlinear field theory are difficult to perform in (3+1)-dimensions, due to the existence of multiple length and time scales. In this paper we study a (2+1)-dimensional analogue of cosmic vortons, which we refer to as kinky vortons, where the cosmic string is replaced by a kink string. Many of the expected qualitative aspects of cosmic vortons transfer to kinky vortons, with the advantage that several approximations used in the study of cosmic vortons can be replaced by exact results. Furthermore, the numerical study of kinky vortons requires less computational resources than cosmic vortons, so a number of issues can be addressed in some depth. The radius of the kinky vorton is determined as a function of the charge and winding number, and it is shown that the chiral limit is a repulsive fixed point. Stability to both axial and non-axial perturbations is demonstrated in the electric and chiral regimes, though surprisingly long lived ringing modes are observed. Kinky vortons which are too magnetic are shown to suffer from a pinching instability, which results in a reduction in the winding number and can convert magnetic into electric solutions.