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Fermion-Antifermion Condensate Contribution to the Anomalous Magnetic Moment of a Fundamental Dirac Fermion

Victor Elias·Kevin Sprague
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Abstract

We consider the contribution of fermion-antifermion condensates to the anomalous magnetic moment of a fermion in a vacuum in which such condensates exist. The real part of the condensate contribution to the anomalous magnetic moment is shown to be zero. A nonzero imaginary part is obtained below the kinematic threshold for intermediate fermion-antifermion pairs. The calculation is shown to be gauge-parameter independent provided a single fermion mass characterizes both the fermion propagator and condensate-sensitive contributions, suggestive of a dynamically-generated fermion mass. The nonzero imaginary part is then argued to correspond to the kinematic production of the intermediate-state Goldstone bosons anticipated from a chiral-noninvariant vacuum. Finally, speculations are presented concerning the applicability of these results to quark electromagnetic properties.

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Victor Elias, Kevin Sprague. 1998-08-10. Fermion-Antifermion Condensate Contribution to the Anomalous Magnetic Moment of a Fundamental Dirac Fermion. https://arxiv.org/abs/hep-ph/9808285

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