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arXiv · 1508.00554

Instanton corrections to the effective action of N=4 SYM

Massimo Bianchi·Jose Francisco Morales·Congkao Wen
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Abstract

We compute the one-instanton effective action of N=4 super Yang-Mills theory with gauge group Sp(2N). The result can be written in a very compact and manifestly supersymmetric form involving an integral over the superspace of an irrational function of the N=4 on-shell superfields. In the Coulomb branch, the instanton corrects both the MHV and next-to-next-MHV higher derivative terms D^4F^{2n+2} and F^{2n+4}. We confirm at the non-perturbative level the non-renormalization theorems for MHV F^{2n+2} terms that are expected to receive perturbative corrections only at n-loops. We compute also the one and two-loop corrections to the D^4F^4 term and show that its completion under SL(2,Z) duality is consistent with the one-instanton results of U(2) gauge group.

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Massimo Bianchi, Jose Francisco Morales, Congkao Wen. 2015-08-03. Instanton corrections to the effective action of N=4 SYM. https://arxiv.org/abs/1508.00554

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