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arXiv · 1307.6854

Renormalization of Massless Feynman Amplitudes in Configuration Space

Nikolay M. Nikolov·Raymond Stora·Ivan Todorov
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Abstract

A systematic study of recursive renormalization of Feynman amplitudes is carried out both in Euclidean and in Minkowski configuration space. For a massless quantum field theory (QFT) we use the technique of extending associate homogeneous distributions to complete the renormalization recursion. A homogeneous (Poincare covariant) amplitude is said to be convergent if it admits a (unique covariant) extension as a homogeneous distribution. For any amplitude without subdivergences - i.e. for a Feynman distribution that is homogeneous off the full (small) diagonal - we define a renormalization invariant residue. Its vanishing is a necessary and sufficient condition for the convergence of such an amplitude. It extends to arbitrary - not necessarily primitively divergent - Feynman amplitudes. This notion of convergence is finer than the usual power counting criterion and includes cancellation of divergences.

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Nikolay M. Nikolov, Raymond Stora, Ivan Todorov. 2013-07-25. Renormalization of Massless Feynman Amplitudes in Configuration Space. https://doi.org/10.1142/s0129055x14300027

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