NONPERTURBATIVE UNIFICATION IN THE LIGHT OF LEP RESULTS

We consider an alternative to conventional grand unified theories orig inally proposed by Maiani, Parisi and Petronzio, where owing to the ex istence of extra fermion generations at some intermediate scale, the g auge couplings become large at high energies. We first comment on how the non-supersymmetric version of this scenario is ruled out; we then consider the two-loop evolution of couplings in the supersymmetric ext ension of this scenario, and check whether such a scenario is feasible in the light of the precise values of couplings now available from LE P.