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Complete Low-Energy Effective action in N=4 SYM: a Direct N=2 Supergraph Calculation

I. L. Buchbinder·E. A. Ivanov·A. Yu. Petrov
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Abstract

Using the covariant N=2 harmonic supergraph techniques we calculate the one-loop low-energy effective action of N=4 super-Yang-Mills theory in Coulomb branch with gauge group SU(2) spontaneously broken down to U(1). The full dependence of the low-energy effective action on both the hypermultiplet and gauge fields is determined. The direct quantum calculation confirms the correctness of the exact N=4 SYM low-energy effective action derived in hep-th/0111062 on the purely algebraic ground by invoking a hidden N=2 supersymmetry which completes the manifest N=2 one to N=4. Our results provide an exhaustive solution to the problem of finding out the exact completely N=4 supersymmetric low-energy effective action for the theory under consideration.

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I. L. Buchbinder, E. A. Ivanov, A. Yu. Petrov. 2002-11-01. Complete Low-Energy Effective action in N=4 SYM: a Direct N=2 Supergraph Calculation. https://doi.org/10.1016/s0550-3213(03)00036-1

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