Loops, cutoffs, and anomalous gauge boson couplings

We discuss several issues regarding analyses which use loop calculations to put constraints on anomalous trilinear gauge boson couplings (TGCs). Many such analyses give far too stringent bounds. This is independent of questions of gauge invariance, contrary to the recent claims of de Rújula et al., since the lagrangians used in these calculations are gauge invariant, but the SU (2) L ×U(1) Y symmetry is nonlinearly realized. The real source of …