First lattice evidence for a non-trivial renormalization of the Higgs condensate

Abstract

General arguments related to ``triviality'' predict that, in the broken phase of $(\hat{I}»\hat{I}{¦}^4{)}_4$ theory, the condensate $<\hat{I}¦>$ re-scales by a factor $Z_{\ddot{I}}•$ different from the conventional wavefunction-renormalization factor, $Z_{prop}$. Using a lattice simulation in the Ising limit we measure $Z_{\ddot{I}}•=m^2\ddot{I}‡$ from the physical mass and susceptibility and $Z_{prop}$ from the residue of the shifted-field propagator. We find that the two $Z$'s differ, with the difference increasing rapidly as the continuum limit is approached. Since $Z_{\ddot{I}}•$ affects the relation of $<\hat{I}¦>$ to the Fermi constant it can sizeably affect the present bounds on the Higgs mass.

10 pages, 3 figures, 1 table, Latex2e