Testing nonperturbative techniques in the scalar sector of the standard model - art. no. 114003

We discuss the current picture of the standard model scalar sector at stron g coupling. We compare the pattern observed in the scalar sector in perturb ation theory up to two loops with the nonperturbative solution obtained by a next-to-leading order 1/N expansion. In particular, we analyze two resona nt Higgs scattering processess <f(f)over bar>-->H-->f'(f) over bar' and <f( f)over bar>-->H-->ZZ, WW. We describe the ingredients of the nonperturbativ e calculation, such as tachyonic regularization, higher order 1/N intermedi ate renormalization, and the numerical methods for evaluating the graphs. W e discuss briefly the perspectives and usefulness of extending these nonper turbative methods to other theories. [S0556-2821(99)03119-7].