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  • Open Access

Bootstrapping the leading hadronic muon anomaly

Ahmadullah Zahed*

  • *Contact author: azahed@ictp.it
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Phys. Rev. D 112, 034031 – Published 26 August, 2025

DOI: https://doi.org/10.1103/3gs1-8s82

Abstract

We bootstrap the leading-order hadronic contribution to aμ using unitarity, analytic properties, crossing symmetry and finite energy sum rules (FESR) from QCD, establishing a lower bound. Combining this lower bound with the remaining precisely calculated contributions from quantum electrodynamics and electroweak interactions, we achieve a lower bound on muon anomaly aμ. Since the FESRs have uncertainties, our bound depends on the choices of FESRs within these uncertainties. A conservative choice of the FESR gives a conservative lower bound, consistent with Standard Model (SM) data-driven prediction. We show that there are other valid choices of FESRs within the uncertainties that lead to lower bounds, which are inconsistent with SM data-driven prediction but consistent with the measured values of the muon anomaly. The bootstrapped spectral density shows a ρ-resonance peak similar to experimental hadronic cross-ratio data, providing a bootstrap prediction for ρ-meson mass.

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Phys. Rev. D 112, 034031– Published 26 August, 2025
  • Received 18 January 2025
  • Accepted 4 August 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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