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arXiv · hep-th/9710145

Hard-Soft Renormalization and the Exact Renormalization Group

M. Pernici·M. Raciti·F. Riva
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Abstract

The Wilsonian exact renormalization group gives a natural framework in which ultraviolet and infrared divergences can be treated separately. In massless QED we introduce, as the only mass parameter, a renormalization scale $Ł_R > 0$. We prove, using the flow equation technique, that infrared convergence is a necessary consequence of any zero-momentum renormalization condition at $Ł_R$ compatible with the effective Ward identities and axial symmetry. The same formalism is applied to renormalize gauge-invariant composite operators and to prove their infrared finiteness; in particular we consider the case of the axial current operator and its anomaly.

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M. Pernici, M. Raciti, F. Riva. 1998-03-06. Hard-Soft Renormalization and the Exact Renormalization Group. https://doi.org/10.1016/s0550-3213(98)00176-x

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