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Explicit construction of nilpotent covariants in N=4 SYM

P. S. Howe·C. Schubert·E. Sokatchev·P. C. West
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Abstract

Some aspects of correlation functions in N=4 SYM are discussed. Using N=4 harmonic superspace we study two and three-point correlation functions which are of contact type and argue that these contact terms will not affect the non-renormalisation theorem for such correlators at non-coincident points. We then present a perturbative calculation of a five-point function at two loops in N=2 harmonic superspace and verify that it reproduces the derivative of the previously found four-point function with respect to the coupling. The calculation of this four-point function via the five-point function turns out to be significantly simpler than the original direct calculation. This calculation also provides an explicit construction of an N=2 component of an N=4 five-point nilpotent covariant that violates U(1)_Y symmetry.

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P. S. Howe, C. Schubert, E. Sokatchev, P. C. West. 1999-10-01. Explicit construction of nilpotent covariants in N=4 SYM. https://doi.org/10.1016/s0550-3213(99)00768-3

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