Warped Angle-deficit of a 5 Dimensional Cosmic String
  We present a cosmic string on a warped five dimensional space time in Einstein-Yang-Mills theory. Four-dimensional cosmic strings show some serious problems concerning the mechanism of string smoothing related to the string mass per unit length, $G\mu \approx 10^{-6}$. A warped cosmic string could overcome this problem and also the superstring requirement that $G\mu$ must be of order 1, which is far above observational bounds. Also the absence of observational evidence of axially symmetric lensing effect caused by cosmic strings could be explained by the warped cosmic string model we present: the angle deficit of the string is warped down to unobservable value in the brane, compared to its value in the bulk. It turns out that only for negative cosmological constant, a consistent numerical solution of the model is possible. 
Reinoud Jan Slagter, Derk Masselink
gr-qc hep-th