Selfexcited cosmic string dynamos
Abstract
Cosmic strings, topological remnants of the earlier universe, arise in many grand unified theories. Witten^{1} showed that under some conditions these strings can behave like superconductors: current is carried by massless charge carriers, which can be either fermions or bosons, that move at the speed of light along the string. These strings are superconductors in the sense that any induced constant current (d.c.) will persist. The persistence is guaranteed by topological index theorems^{1}, but no such theorem exists for alternating currents (a.c.), which can be damped by radiation or (as we report here) can even grow exponentially through dynamo selfinteraction. This mechanism converts the mechanical energy of the string into electromagnetic fields.
 Publication:

Nature
 Pub Date:
 August 1988
 DOI:
 10.1038/334682a0
 Bibcode:
 1988Natur.334..682S
 Keywords:

 Dynamo Theory;
 String Theory;
 Unified Field Theory;
 Universe;
 Oscillations;
 Topology;
 Trajectory Analysis;
 Astrophysics