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Nonlocal Regularization and Spontaneously Broken Abelian Gauge Theories for an Arbitrary Gauge Parameter

A. Basu·S. D. Joglekar
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Abstract

We study the non-local regularization for the case of a spontaneously broken abelian gauge theory in the R_xi gauge with an arbitrary gauge parameter xi. We consider a simple abelian-Higgs model with chiral couplings as an example. We show that if we apply the nonlocal regularization procedure [to construct a nonlocal theory with finite mass parameter ] to the spontaneously broken R_xi gauge Lagrangian, using the quadratic forms as appearing in this Lagrangian, we find that a physical observable in this model, an analogue of the muon anomalous magnetic moment, evaluated to order O[g^{2}] does indeed show xi-dependence.We then apply the modified form of nonlocal regularization that was recently advanced and studied for the unbroken non-abelian gauge theories and discuss the resulting WT identities and xi-independence of the S-matrix elements.

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A. Basu, S. D. Joglekar. 2001-02-28. Nonlocal Regularization and Spontaneously Broken Abelian Gauge Theories for an Arbitrary Gauge Parameter. https://arxiv.org/abs/hep-th/0102171

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