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One-loop four-point function in noncommutative {\cal N}=4 Yang-Mills theory

Alberto Santambrogio·Daniela Zanon
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Abstract

We compute the one-loop four-point function in {\cal N}=4 supersymmetric Yang-Mills theory with gauge group U(N). We perform the calculation in {\cal N}=1 superspace using the background field method and obtain the complete off-shell contributions to the effective action from planar and non planar supergraphs. In the low-energy approximation the result simplifies and we can study its properties under gauge transformations. It appears that the nonplanar contributions do not maintain the gauge invariance of the classical action.

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Alberto Santambrogio, Daniela Zanon. 2000-10-30. One-loop four-point function in noncommutative {\cal N}=4 Yang-Mills theory. https://doi.org/10.1088/1126-6708%2F2001%2F01%2F024

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