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arXiv · 0908.4339

Instanton Calculus in Deformed N=4 Super Yang-Mills Theories

Katsushi Ito·Hiroaki Nakajima·Takuya Saka·Shin Sasaki
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Abstract

We study the instanton effective action of four-dimensional deformed N=4 supersymmetric Yang-Mills theory in the presence of constant, self-dual Ramond-Ramond (R-R) 3-form background in type IIB superstring theory. We compare the instanton effective action with the low-energy effective action on D(-1)-branes in the D3-D(-1) system in the same background. We find that discrepancy appears at the second order of the R-R background, which was also observed in deformed N=2 theory. This discrepancy is resolved if the action of the deformed gauge theory is improved by introducing a term with coordinate-dependent gauge coupling. We obtain the same deformed instanton effective action from super Yang-Mills theory in ten-dimensional Omega-background by dimensional reduction. We also discuss another type of R-R 3-form background which corresponds to massive deformations of the instanton effective action.

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Katsushi Ito, Hiroaki Nakajima, Takuya Saka, Shin Sasaki. 2009-08-29. Instanton Calculus in Deformed N=4 Super Yang-Mills Theories. https://doi.org/10.1088/1126-6708/2009/10/028

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