Short-distance constraints in hadronic-light-by-light for the muon $g-2$

TL;DR

This paper discusses recent advances in understanding the short-distance behavior of the hadronic light-by-light contribution to the muon g-2, crucial for refining theoretical predictions and reducing uncertainties.

Contribution

It introduces a systematic expansion at short distances showing the massless quark-loop as the leading term and confirms control over nonperturbative and perturbative corrections.

Findings

Massless quark-loop as leading short-distance term

Nonperturbative and perturbative corrections are well-controlled

Improved understanding of the hadronic light-by-light contribution

Abstract

In this talk recent progress in studying the short-distance properties of the hadronic light-by-light contribution to the muon $g-2$ is described. The intermediate and short-distance part is a major contributor to the error of the theoretical prediction as described in the recent white paper [1]. We have shown that the massless quark-loop is the first term in a systematic expansion at short-distances, a result already used in the white paper. Newer results conclude that both nonperturbative and perturbative corrections are under control. The talk describes these developments and how they fit in the total theoretical prediction for the muon $g-2$.