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arXiv · hep-ph/0610293

A novel approach to light-front perturbation theory

T. Heinzl
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Abstract

We suggest a possible algorithm to calculate one-loop n-point functions within a variant of light-front perturbation theory. The key ingredients are the covariant Passarino-Veltman scheme and a surprising integration formula that localises Feynman integrals at vanishing longitudinal momentum. The resulting expressions are generalisations of Weinberg's infinite-momentum results and are manifestly Lorentz invariant. For n = 2 and 3 we explicitly show how to relate those to light-front integrals with standard energy denominators. All expressions are rendered finite by means of transverse dimensional regularisation.

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T. Heinzl. 2006-10-23. A novel approach to light-front perturbation theory. https://doi.org/10.1103/physrevd.75.025013

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