2-LOOP HEAVY HIGGS CORRECTIONS TO THE HIGGS FERMIONIC WIDTH

We calculate the two-loop electroweak corrections to the fermionic decay width of the Higgs boson at leading order in m(H). The sum of one-loop and two-loop radiative corrections turns out to be at the 6% level over the whole range of m(H) where the perturbation theory is supposed to be a sensible approximation. We show that the perturbative approach breaks down at m(H) similar to 1.4 TeV, and address the question of its relevance beyond this limit.