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arXiv · 1006.5640

Nonperturbative calculation of the anomalous magnetic moment in the Yukawa model within truncated Fock space

V. A. Karmanov·J. -F. Mathiot·A. V. Smirnov
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Abstract

Within the covariant formulation of light-front dynamics, we calculate the state vector of a physical fermion in the Yukawa model. The state vector is decomposed in Fock sectors and we consider the first three ones: the single constituent fermion, the constituent fermion coupled to one scalar boson, and the constituent fermion coupled to two scalar bosons. This last three-body sector generates nontrivial and nonperturbative contributions to the state vector, which are calculated numerically. Field-theoretical divergences are regularized using Pauli-Villars fermion and boson fields. Physical observables can be unambiguously deduced using a systematic renormalization scheme we have developed previously. As a first application, we consider the anomalous magnetic moment of the physical fermion.

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V. A. Karmanov, J. -F. Mathiot, A. V. Smirnov. 2010-06-29. Nonperturbative calculation of the anomalous magnetic moment in the Yukawa model within truncated Fock space. https://doi.org/10.1103/physrevd.82.056010

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