Diphoton decay of the higgs from the Epstein--Glaser viewpoint

TL;DR

This paper reexamines the Higgs diphoton decay controversy using Epstein--Glaser renormalization, avoiding regularization techniques and expanding the method's toolkit to clarify the theoretical understanding.

Contribution

It introduces a regularization-free Epstein--Glaser approach to Higgs decay, expanding the method's toolkit and resolving longstanding debates.

Findings

Clarified the diphoton decay mechanism of the Higgs

Demonstrated the effectiveness of Epstein--Glaser renormalization without regularization

Provided a new perspective on quantum field theory calculations

Abstract

We revisit a nearly ten-year old controversy on the diphoton decay of the Higgs particle. To a large extent, the controversy turned around the respective merits of the regularization techniques employed. The novel aspect of our approach is that no regularization techniques are brought to bear: we work within the Bogoliubov--Epstein--Glaser scheme of renormalization by extension of distributions. Solving the problem actually required an expansion of this method's toolkit, furnished in the paper.