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arXiv · 1111.0083

From Scattering Amplitudes to the Dilatation Generator in N=4 SYM

Benjamin I. Zwiebel
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Abstract

The complete spin chain representation of the planar N=4 SYM dilatation generator has long been known at one loop, where it involves leading nearest-neighbor 2 -> 2 interactions. In this work we use superconformal symmetry to derive the unique solution for the leading L -> 2 interactions of the planar dilatation generator for arbitrarily large L. We then propose that these interactions are given by the scattering operator that has N=4 SYM tree-level scattering amplitudes as matrix elements. We provide compelling evidence for this proposal, including explicit checks for L=2,3 and a proof of consistency with superconformal symmetry.

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Benjamin I. Zwiebel. 2011-11-01. From Scattering Amplitudes to the Dilatation Generator in N=4 SYM. https://doi.org/10.1088/1751-8113/45/11/115401

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