The conservation of the vector current and the axial anomaly responsible for the pi(0) -> gamma gamma decay amplitude are obtained in leading order within the Taylor-Lagrange formulation of fields considered as operator-valued distributions. As for gauge theories, where this formulation eliminates all divergences and preserves gauge symmetry, it is shown that the different contributions can be evaluated directly in four-dimensional space-time, with no restrictions whatsoever on the four-momentum of the internal loop, and without the need to introduce any additional nonphysical degrees of freedom like Pauli-Villars fields. We comment on the similar contributions responsible for the decay of the Higgs boson into two photons.
展开▼
