Discrete Spacetime Theories Can Explain the Muon Magnetic Moment Discrepancy

TL;DR

This paper proposes that a fundamental length scale in spacetime, modeled through Doubly Special Relativity, can explain the muon magnetic moment discrepancy by modifying the photon propagator, with testable predictions at future colliders.

Contribution

It introduces a novel explanation for the muon g-2 anomaly based on spacetime graininess at a specific length scale within DSR framework.

Findings

A fundamental length scale of 10^{-22} m can account for the muon g-2 discrepancy.

The scale is within reach of next-generation collider experiments.

The proposed model links spacetime structure to particle physics anomalies.

Abstract

An unsolved problem of particle physics is a discrepancy between the measured value of the muon anomalous magnetic moment and the theoretical prediction based on standard quantum electrodynamics. In this paper we show that if spacetime possesses a fundamental length scale, the ensuing modifications to the photon propagator can account for the discrepancy if the scale is chosen to be $10^{-22}$~m; the corresponding energy being about $30$~TeV. The possibility that spacetime possesses a graininess on a fine enough scale has a long history. One class of theories that develops this idea is Doubly Special Relativity (DSR), and we choose this as a model for our calculation. We note that the derived length scale is many orders of magnitude larger than the Planck length, but comparable to that of some higher dimensional gravitational theories. It is also within scope of experimental confirmation in the next generation of colliders.