# Instantons in Deformed Super Yang-Mills Theories - High Energy Physics - Theory

Abstract: We study the instanton effective action in deformed four-dimensional N=2 andN=4 super Yang-Mills SYM theories. These deformed gauge theories are definedon the D-brane world-volume in the presence of constant, self-dualRamond-Ramond R-R 3-form field strength background $\mathcal{F}$ which isscaled as $2 \pi \alpha-^{1-2} \mathcal{F} = fixed$ in the zero-slope limit$\alpha- \to 0$. The instanton effective action is obtained by solvingequations of motion of the deformed N=2 SYM action. We show that this effectiveaction correctly reproduces the string theory result derived fromD3-D-1-branes system in the lowest order of the backgrounds and gaugecoupling constant.

Author: Shin Sasaki, Katsushi Ito, Hiroaki Nakajima

Source: https://arxiv.org/