# The hadronic light-by-light contribution to the muon's anomalous magnetic moment

## TL;DR

This paper reviews efforts to precisely determine the hadronic light-by-light contribution to the muon's anomalous magnetic moment, aiming to resolve the current discrepancy between theory and experiment.

## Contribution

It introduces dispersive techniques combined with experimental data to improve the accuracy of the hadronic light-by-light contribution estimation.

## Key findings

- Dispersive methods help constrain the hadronic light-by-light contribution.
- Experimental data is crucial for reducing uncertainties.
- Progress is being made towards resolving the muon g-2 discrepancy.

## Abstract

In view of the current 3 - 4 $\sigma$ deviation between theoretical and experimental values for the muon's anomalous magnetic moment, we review the ongoing efforts in constraining the hadronic light-by-light contribution to $a_\mu$ by using dispersive techniques combined with a dedicated experimental program to obtain the required hadronic input.