From Loops to Trees By-passing Feynman's Theorem

Catani, Stefano ; Gleisberg, Tanju ; Krauss, Frank ; Rodrigo, German ; Winter, Jan-Christopher

Stanford Linear Accelerator Center

关键词: Modifications;    Duality;    Field Theories;    Scattering Amplitudes Phenomenology-Hep,Hepph;    Cross Sections;   

DOI  :  10.2172/927533
RP-ID  :  SLAC-PUB-13218
RP-ID  :  AC02-76SF00515
RP-ID  :  927533

美国|英语

来源: UNT Digital Library

【 摘 要 】

We derive a duality relation between one-loop integrals and phase-space integrals emerging from them through single cuts. The duality relation is realized 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 applied to generic one-loop quantities in any relativistic, local and unitary field theories. It is suitable for applications to the analytical calculation of one-loop scattering amplitudes, and to the numerical evaluation of cross-sections at next-to-leading order.