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arXiv · 1511.05016

Bremsstrahlung function, leading Luscher correction at weak coupling and localization

Marisa Bonini·Luca Griguolo·Michelangelo Preti·Domenico Seminara
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Abstract

We discuss the near BPS expansion of the generalized cusp anomalous dimension with L units of R-charge. Integrability provides an exact solution, obtained by solving a general TBA equation in the appropriate limit: we propose here an alternative method based on supersymmetric localization. The basic idea is to relate the computation to the vacuum expectation value of certain 1/8 BPS Wilson loops with local operator insertions along the contour. These observables localize on a two-dimensional gauge theory on S^2, opening the possibility of exact calculations. As a test of our proposal, we reproduce the leading Luscher correction at weak coupling to the generalized cusp anomalous dimension. This result is also checked against a genuine Feynman diagram approach in N=4 Super Yang-Mills theory.

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Marisa Bonini, Luca Griguolo, Michelangelo Preti, Domenico Seminara. 2015-11-27. Bremsstrahlung function, leading Luscher correction at weak coupling and localization. https://doi.org/10.1007/jhep02(2016)172

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