Cusp anomalous dimension in maximally supersymmetric
نویسنده
چکیده
This talk is mainly based on the work [1] performed in collaboration with B. Basso1 and G. Korchemsky1, where the method of strong coupling expansion of the cusp anomalous dimension was found. The cusp anomalous dimension [2], called also the cusp, is a physical observable, which appears in many branches of particle physics. It is related with the logarithmic growth of the anomalous dimensions of high-spin Wilson operators and with the gluon Regge trajectory, it governs behavior of the Sudakov form factors as well as it defines infrared singularities of on-shell scattering amplitude. In order to define the cusp anomalous dimension in in N = 4 supersymmetric Yang-Mills (MSYM) theory one can consider local operators composed of L scalar fields and S covariant derivatives, 〈Ds1XDs2X . . . DsLX〉, with the spin S = ∑L k=1 sk. In the high spin limit the anomalous dimensions of these operators read as
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