# Sharpening The Leading Singularity

@article{Cachazo2008SharpeningTL, title={Sharpening The Leading Singularity}, author={Freddy Cachazo}, journal={arXiv: High Energy Physics - Theory}, year={2008} }

W e show how studying leading singularitiesofFeynm an diagram s,when allm om enta are com plex,givesa sim ple way ofwriting m ulti-loop and m ulti-particle scattering am plitudesin N = 4 superYang-M ills.Thesim plicity ofthem ethod isequivalenttothatofthequadruplecuttechnique introduced in hep-th/0412103 atone-loop. The new technique only involves the com putation of residuesand the solution oflinear equations. In our technique both parity even and parity odd

## 127 Citations

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