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arXiv · 0911.4455

A nonperturbative calculation of the electron's magnetic moment with truncation extended to two photons

S. S. Chabysheva·J. R. Hiller
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Abstract

The Pauli--Villars (PV) regularization scheme is applied to a calculation of the dressed-electron state and its anomalous magnetic moment in light-front-quantized quantum electrodynamics (QED) in Feynman gauge. The regularization is provided by heavy, negative-metric fields added to the Lagrangian. The light-front QED Hamiltonian then leads to a well-defined eigenvalue problem for the dressed-electron state expressed as a Fock-state expansion. The Fock-state wave functions satisfy coupled integral equations that come from this eigenproblem. A finite system of equations is obtained by truncation to no more than two photons and no positrons; this extends earlier work that was limited to dressing by a single photon. Numerical techniques are applied to solve the coupled system and compute the anomalous moment, for which we obtain agreement with experiment, within numerical errors, but observe a small systematic discrepancy that should be due to the absence of electron-positron loops and of three-photon self-energy effects. We also discuss the prospects for application of the method to quantum chromodynamics.

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S. S. Chabysheva, J. R. Hiller. 2009-11-23. A nonperturbative calculation of the electron's magnetic moment with truncation extended to two photons. https://doi.org/10.1103/physrevd.81.074030

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