In this paper, we present a formalism for computing the Yukawa couplings in heterotic standard models. This is accomplished by calculating the relevant triple products of cohomology groups, leading to terms proportional to Q*H*u, Q*Hbar*d, L*H*nu and L*Hbar*e in the low energy superpotential. These interactions are subject to two very restrictive selection rules arising from the geometry of the Calabi-Yau manifold. We apply our formalism to the "minimal" heterotic standard model whose observable sector matter spectrum is exactly that of the MSSM. The non-vanishing Yukawa interactions are explicitly computed in this context. These interactions exhibit a texture rendering one out of the three quark/lepton families naturally light.
@article{arxiv.hep-th/0601204,
title = {Yukawa Couplings in Heterotic Standard Models},
author = {Volker Braun and Yang-Hui He and Burt A. Ovrut},
journal= {arXiv preprint arXiv:hep-th/0601204},
year = {2010}
}