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arXiv · 1904.00965

Octagons I: Combinatorics and Non-Planar Resummations

Till Bargheer·Frank Coronado·Pedro Vieira
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Abstract

We explain how the 't Hooft expansion of correlators of half-BPS operators can be resummed in a large-charge limit in N=4 super Yang-Mills theory. The full correlator in the limit is given by a non-trivial function of two variables: One variable is the charge of the BPS operators divided by the square root of the number Nc of colors; the other variable is the octagon that contains all the 't Hooft coupling and spacetime dependence. At each genus g in the large Nc expansion, this function is a polynomial of degree 2g+2 in the octagon. We find several dual matrix model representations of the correlators in the large-charge limit. Amusingly, the number of colors in these matrix models is formally taken to zero in the relevant limit.

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Till Bargheer, Frank Coronado, Pedro Vieira. 2019-04-01. Octagons I: Combinatorics and Non-Planar Resummations. https://doi.org/10.1007/jhep08(2019)162

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