Fermion Masses in Superstring Theory

Abstract

We give a model-independent discussion of fermion masses in four-dimensional heterotic superstring theories. We discuss the tree level contributions and quantum corrections, including one-loop threshold effects and masses generated as a result of non-perturbative supersymmetry breaking. We also point out that superstring models give rise to a generic $\mu$-term in the effective low energy Lagrangian.

Comments: 13 pages, latex. Based on talks presented at the Spring Workshop on String Theory, ICTP, Trieste, 11-22 April 1994, and at the Joint U.S.-Polish Workshop on Physics from Planck Scale to Electroweak Scale, Warsaw, Poland, 21-24 September 1994