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Instantons and Non-renormalisation in AdS/CFT

Rajesh Gopakumar·Michael B. Green
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Abstract

The series of perturbative fluctuations around a multi-instanton contribution to a specific class of correlation functions of supercurrents in $\cal N=4$ supersymmetric SU(N) Yang-Mills theory is examined in the light of the AdS/CFT correspondence. Subject to certain plausible assumptions, we argue that a given term in the 1/N expansion in such a background receives only a finite number of perturbative corrections in the 't Hooft limit. Such instanton non-renormalisation theorems would explain, for example, the exact agreement of certain weak coupling Yang-Mills instanton calculations with the strong coupling predictions arising from D-instanton effects in string theory amplitudes. These non-renormalisation theorems essentially follow from the assumption of a well defined derivative $(α^{\prime})$ expansion in the string theory dual of the Yang-Mills theory.

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Rajesh Gopakumar, Michael B. Green. 1999-11-23. Instantons and Non-renormalisation in AdS/CFT. https://doi.org/10.1088/1126-6708%2F1999%2F12%2F015

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