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arXiv · hep-th/0410054

Loops in Twistor Space

Iosif Bena·Zvi Bern·David A. Kosower·Radu Roiban
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Abstract

We elucidate the one-loop twistor-space structure corresponding to momentum-space MHV diagrams. We also discuss the infrared divergences, and argue that only a limited set of MHV diagrams contain them. We show how to introduce a twistor-space regulator corresponding to dimensional regularization for the infrared-divergent diagrams. We also evaluate explicitly the `holomorphic anomaly' pointed out by Cachazo, Svrcek, and Witten, and use the result to define modified differential operators which can be used to probe the twistor-space structure of one-loop amplitudes.

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Iosif Bena, Zvi Bern, David A. Kosower, Radu Roiban. 2005-01-12. Loops in Twistor Space. https://doi.org/10.1103/physrevd.71.106010

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