ar X iv : h ep - p h / 02 10 13 0 v 3 6 A pr 2 00 5 YITP - SB - 02 - 56 Multi - loop Amplitudes and Resummation ⋆
نویسنده
چکیده
We explore the relation between resummation and explicit multi-loop calculations for QCD hard-scattering amplitudes. We describe how the factorization properties of amplitudes lead to the exponentiation of double and single poles at each order of perturbation theory. For these amplitudes, previously-observed relations between single and double poles in different 2 → 2 processes can now be interpreted in terms of universal functions associated with external partons and process-dependent anomalous dimensions that describe coherent soft radiation. Catani’s proposal for multiple poles in dimensionally-continued amplitudes emerges naturally.
منابع مشابه
ar X iv : h ep - p h / 02 10 13 0 v 2 1 0 O ct 2 00 2 YITP - SB - 02 - 56 Multi - loop Amplitudes and Resummation ⋆
We explore the relation between resummation and explicit multi-loop calculations for QCD hard-scattering amplitudes. We describe how the factorization properties of amplitudes lead to the exponentiation of double and single poles at each order of perturbation theory. For these amplitudes, previously-observed relations between single and double poles in different 2 → 2 processes can now be inter...
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