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arXiv · hep-th/9803184

Regularization schemes and the multiplicative anomaly

T. S. Evans
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Abstract

Elizalde, Vanzo, and Zerbini have shown that the effective action of two free Euclidean scalar fields in flat space contains a `multiplicative anomaly' when zeta-function regularization is used. This is related to the Wodzicki residue. I show that there is no anomaly when using a wide range of other regularization schemes and further that this anomaly can be removed by an unusual choice of renormalisation scales. I define new types of anomalies and show that they have similar properties. Thus multiplicative anomalies encode no novel physics. They merely illustrate some dangerous aspects of zeta-function and Schwinger proper time regularization schemes.

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T. S. Evans. 1999-04-22. Regularization schemes and the multiplicative anomaly. https://doi.org/10.1016/s0370-2693(99)00503-1

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