Top Quark Mass Predictions from Gauge - Yukawa Unification

Gauge-Yukawa Unification (GYU) is a renormalization group invariant functional relation among gauge and Yukawa couplings which holds beyond the unification point in Grand Unified Theories (GUTs). Here, GYU is obtained by requiring finiteness and reduction of couplings to all orders in perturbation theory. We examine the consequences of GYU in various supersymmetric GUTs and in particular the predictions for the top quark mass. These predictions are such that they distinguish already GYU from ordinary GUTs. Moreover, when more accurate measurements of the top quark mass are available, it is expected that it will be possible to discriminate among the various GYUs. † Presented by G. Zoupanos at the ’95 Summer School on HEP and Cosmology (ICTP, Trieste). Partially supported by the Grants-in-Aid for Scientific Research from the Ministry of Education, Science and Culture (No. 40211213). Address after Jan. 1st, ’96: Instituto de F́ısica, UNAM, Apdo. Postal 20-364, México 01000 D.F., México. On leave of absence from Physics Department, National Technical University, GR-157 80 Zografou, Athens, Greece. Partially supported by C.E.C. projects, SC1-CT91-0729; CHRX-CT93-0319.