2005/10/04 by Joseph Polchinski · 1 voice · 1 citation
Physics and Astronomy · #hep-th
paper · pdf · doi:10.1088/1126-6708/2006/09/082
published as JHEP 0609:082,2006 · 15 pages. v.2: typos, references corrected
arxiv published 2005/10/04 · arxiv created 2005/10/07 · arxiv updated 2005/10/07
We classify potential cosmic strings according to the topological charge measurable outside the string core. We conjecture that in string theory it is this charge that governs the stability of long strings. This would imply that the SO(32) heterotic string can have endpoints, but not the E8 x E8 heterotic string. We give various arguments in support of this conclusion.