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arXiv · 1603.02768

The low-energy N=4 SYM effective action in diverse harmonic superspaces

I. L. Buchbinder·E. A. Ivanov·I. B. Samsonov
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Abstract

We review various superspace approaches to the description of the low-energy effective action in N=4 super Yang-Mills (SYM) theory. We consider the four-derivative part of the low-energy effective action in the Coulomb branch. The typical components of this effective action are the gauge field F^4/X^4 and the scalar field Wess-Zumino terms. We construct N=4 supersymmetric completions of these terms in the framework of different harmonic superspaces supporting N=2,3,4 supersymmetries. These approaches are complementary to each other in the sense that they make manifest different subgroups of the total SU(4) R-symmetry group. We show that the effective action acquires an extremely simple form in those superspaces which manifest the non-anomalous maximal subgroups of SU(4). The common characteristic feature of our construction is that we restore the superfield effective actions exclusively by employing the N=4 supersymmetry and/or superconformal PSU(2,2|4) symmetry.

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I. L. Buchbinder, E. A. Ivanov, I. B. Samsonov. 2016-03-09. The low-energy N=4 SYM effective action in diverse harmonic superspaces. https://doi.org/10.1134/s1063779617030042

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