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arXiv · 1512.05362

On level crossing in conformal field theories

G. P. Korchemsky
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Abstract

We study the properties of operators in a unitary conformal field theory whose scaling dimensions approach each other for some values of the parameters and satisfy von Neumann-Wigner non-crossing rule. We argue that the scaling dimensions of such operators and their OPE coefficients have a universal scaling behavior in the vicinity of the crossing point. We demonstrate that the obtained relations are in a good agreement with the known examples of the level-crossing phenomenon in maximally supersymmetric $\mathcal N=4$ Yang-Mills theory, three-dimensional conformal field theories and QCD.

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G. P. Korchemsky. 2016-01-20. On level crossing in conformal field theories. https://doi.org/10.1007/jhep03(2016)212

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