Unification and fermion mass relations in low string scale D-brane models
arXiv:hep-ph/0605278 · doi:10.1088/1742-6596/53/1/044
Abstract
In this talk, gauge coupling evolution is analyzed in D-brane inspired models with two Higgs doublets and a U(3)xU(2)xU(1)^N gauge symmetry. In particular, we focus on D-brane configurations with two or three abelian factors. We find that the correct hypercharge assignment of the Standard Model particles is reproduced for six viable models distinguished by different brane configurations. We also investigate the bottom tau quark mass relation and find that the correct low energy m_b / m_τratio is obtained for equal b-τYukawa couplings at a string scale around 10^3 TeV.
10 pages, 3 figures. Talk presented at the ``Corfu Summer Institute'', Corfu-Greece, September 4-14, 2005. To appear in the proceedings of RTN workshop on the Quest for Unification Theory Confronts Experiment