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arXiv · hep-th/9811190

Path Integrals, BRST Identities and Regularization Schemes in Nonstandard Gauges

Hai-cang Ren
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Abstract

The path integral of a gauge theory is studied in Coulomb-like gauges. The Christ-Lee terms of operator ordering are reproduced {\it{within}} the path integration framework. In the presence of fermions, a new operator term, in addition to that of Christ-Lee, is discovered. Such kind of terms is found to be instrumental in restoring the invariance of the effective Lagrangian under a field dependent gauge transformation, which underlies the BRST symmetry. A unitary regularization scheme which maintains manifest BRST symmetry and is free from energy divergences is proposed for a nonabelian gauge field.

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Hai-cang Ren. 1998-11-20. Path Integrals, BRST Identities and Regularization Schemes in Nonstandard Gauges. https://doi.org/10.1006/aphy.2000.6046

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