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arXiv · 0807.0531

From multileg loops to trees (by-passing Feynman's Tree Theorem)

German Rodrigo·Stefano Catani·Tanju Gleisberg·Frank Krauss·Jan-Christopher Winter
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Abstract

We illustrate a duality relation between one-loop integrals and single-cut phase-space integrals. The duality relation is realised by a modification of the customary +i0 prescription of the Feynman propagators. The new prescription regularizing the propagators, which we write in a Lorentz covariant form, compensates for the absence of multiple-cut contributions that appear in the Feynman Tree Theorem. The duality relation can be extended to generic one-loop quantities, such as Green's functions, in any relativistic, local and unitary field theories.

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German Rodrigo, Stefano Catani, Tanju Gleisberg, Frank Krauss, Jan-Christopher Winter. 2008-07-03. From multileg loops to trees (by-passing Feynman's Tree Theorem). https://doi.org/10.1016/j.nuclphysbps.2008.09.114

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