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arXiv · 1704.00448

Instanton effects in correlation functions on the light-cone

G. P. Korchemsky
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Abstract

We study instanton corrections to four-point correlation correlation function of half-BPS operators in $\mathcal N=4$ SYM in the light-cone limit when operators become null separated in a sequential manner. We exploit the relation between the correlation function in this limit and light-like rectangular Wilson loop to determine the leading instanton contribution to the former from the semiclassical result for the latter. We verify that the light-like rectangular Wilson loop satisfies anomalous conformal Ward identities nonperturbatively, in the presence of instantons. We then use these identities to compute the leading instanton contribution to the light-like cusp anomalous dimension and to anomalous dimension of twist-two operators with large spin.

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G. P. Korchemsky. 2017-04-03. Instanton effects in correlation functions on the light-cone. https://doi.org/10.1007/jhep12(2017)093

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