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Regularization of current algebra

Jouko Mickelsson
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Abstract

In this talk I want to explain the operator substractions needed to regularize gauge currents in a second quantized theory. The case of space-time dimension $3+1$ is considered in detail. In presence of chiral fermions the regularization effects a modification of the local commutation relations of the currents by local Schwinger terms. In $1+1$ dimensions one gets the usual central extension (Schwinger term does not depend on background gauge field) whereas in $3+1$ dimensions one gets an anomaly linear in the background potential.

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Jouko Mickelsson. 1993-06-27. Regularization of current algebra. https://arxiv.org/abs/hep-th/9306133

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