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arXiv · hep-th/9905209

Summing the Instanton Series in N=2 Superconformal Large-N QCD

Timothy J. Hollowood·Valentin V. Khoze·Michael P. Mattis
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Abstract

We consider the multi-instanton collective coordinate integration measure in N=2 supersymmetric SU(N) gauge theory with N_F fundamental hypermultiplets. In the large-N limit, at the superconformal point where N_F=2N and all VEVs are turned off, the k-instanton moduli space collapses to a single copy of AdS_5*S^1. The resulting k-instanton effective measure is proportional to N^{1/2} g^4 Z_k^(6), where Z_k^(6) is the partition function of N=(1,0) SYM theory in six dimensions reduced to zero dimensions. The multi-instanton can in fact be summed in closed form. As a hint of an AdS/CFT duality, with the usual relation between the gauge theory and string theory parameters, this precisely matches the normalization of the charge-k D-instanton measure in type IIB string theory compactified to six dimensions on K3 with a vanishing two-cycle.

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Timothy J. Hollowood, Valentin V. Khoze, Michael P. Mattis. 1999-05-27. Summing the Instanton Series in N=2 Superconformal Large-N QCD. https://doi.org/10.1088/1126-6708%2F1999%2F10%2F019

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