Journal of High Energy Physics (Jul 2020)

The Hopf algebra structure of the R∗-operation

  • Robert Beekveldt,
  • Michael Borinsky,
  • Franz Herzog

DOI
https://doi.org/10.1007/JHEP07(2020)061
Journal volume & issue
Vol. 2020, no. 7
pp. 1 – 36

Abstract

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Abstract We give a Hopf-algebraic formulation of the R ∗ -operation, which is a canonical way to render UV and IR divergent Euclidean Feynman diagrams finite. Our analysis uncovers a close connection to Brown’s Hopf algebra of motic graphs. Using this connection we are able to provide a verbose proof of the long observed ‘commutativity’ of UV and IR subtractions. We also give a new duality between UV and IR counterterms, which, entirely algebraic in nature, is formulated as an inverse relation on the group of characters of the Hopf algebra of log-divergent scaleless Feynman graphs. Many explicit examples of calculations with applications to infrared rearrangement are given.

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