Open strings, simple currents and fixed points
arXiv:hep-th/0001198
Abstract
Some applications of simple current techniques and fixed point resolution to theories of open strings are discussed. In addition to a brief review of work presented in two recent papers with L. Huiszoon and N. Sousa, some new results concerning uniqueness of crosscap coefficients are presented, as well as a strange sum rule for the modular matrix implied by the existence of crosscaps.
21 pages, Latex. Invited talk at the Wigner Symposium, 16-22 August 1999, Istanbul, Turkey