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arXiv · 1403.1785

Improved Epstein-Glaser renormalization in $x$-space versus differential renormalization

José M. Gracia-Bondía·Heidy Gutiérrez·Joseph C. Várilly
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Abstract

Renormalization of massless Feynman amplitudes in $x$-space is reexamined here, using almost exclusively real-variable methods. We compute a wealth of concrete examples by means of recursive extension of distributions. This allows us to show perturbative expansions for the four-point and two-point functions at several loop order. To deal with internal vertices, we expound and expand on convolution theory for log-homogeneous distributions. The approach has much in common with differential renormalization as given by Freedman, Johnson and Latorre; but differs in important details.

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José M. Gracia-Bondía, Heidy Gutiérrez, Joseph C. Várilly. 2017-02-22. Improved Epstein-Glaser renormalization in $x$-space versus differential renormalization. https://doi.org/10.1016/j.nuclphysb.2014.07.018

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