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arXiv · hep-th/0212156

Improved Epstein-Glaser Renormalization II. Lorentz invariant framework

J. M. Gracia-Bondia·S. Lazzarini
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Abstract

The Epstein--Glaser type T-subtraction introduced by one of the authors in a previous paper is extended to the Lorentz invariant framework. The advantage of using our subtraction instead of Epstein and Glaser's standard W-subtraction method is especially important when working in Minkowski space, as then the counterterms necessary to keep Lorentz invariance are simplified. We show how T-renormalization of primitive diagrams in the Lorentz invariant framework directly relates to causal Riesz distributions. A covariant subtraction rule in momentum space is found, sharply improving upon the BPHZL method for massless theories.

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J. M. Gracia-Bondia, S. Lazzarini. 2003-05-22. Improved Epstein-Glaser Renormalization II. Lorentz invariant framework. https://doi.org/10.1063/1.1597420

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