Verification of the tenth-Order QED contribution to the anomalous magnetic moment of the electron from diagrams without fermion loops

Tatsumi Aoyama; Masashi Hayakawa; Akira Hirayama; Makiko Nio

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arXiv · 2412.06473

Verification of the tenth-Order QED contribution to the anomalous magnetic moment of the electron from diagrams without fermion loops

Tatsumi Aoyama·Masashi Hayakawa·Akira Hirayama·Makiko Nio

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Abstract

A discrepancy of approximately 5$\sigma$ exists between the two known results for the tenth-order QED contribution to the anomalous magnetic moment of the electron, calculated from Feynman vertex diagrams without fermion loops. To investigate this, we decomposed this contribution into 389 parts based on a self-energy diagram representation, enabling a diagram-by-diagram numerical comparison of the two calculations. No significant discrepancies were found for individual diagrams. However, the numerical differences of the 98 diagrams sharing a common structure were not randomly distributed. The accumulation of these differences resulted in the 5$\sigma$ discrepancy. A recalculation with increased statistics in the Monte Carlo integration was performed for these 98 diagrams. By replacing the old values with the new ones for these 98 integrals, we have obtained a revised result of $6.800 \pm 0.128$, thereby resolving the discrepancy.

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Tatsumi Aoyama, Masashi Hayakawa, Akira Hirayama, Makiko Nio. 2024-12-09. Verification of the tenth-Order QED contribution to the anomalous magnetic moment of the electron from diagrams without fermion loops. https://arxiv.org/abs/2412.06473

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