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arXiv · hep-th/0605080

AdS/CFT v.s. String Loops

Gianluca Grignani·Marta Orselli·Bojan Ramadanovic·Gordon W. Semenoff·Donovan Young
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Abstract

The one string-loop correction to the energies of two impurity BMN states are computed using IIB light-cone string field theory with an improved 3-string vertex that has been proposed by Dobashi and Yoneya. As in previous published computations, the string vertices are truncated to the 2-impurity channel. The result is compared with the prediction from non-planar corrections in the BMN limit of $\mathcal{N}=4$ supersymmetric Yang-Mills theory. It is found to agree at leading order -- one-loop in Yang-Mills theory -- and is close but not quite in agreement at order two Yang-Mills loops. Furthermore, in addition to the leading 1/2 power in the t'Hooft coupling, which is generic in string field theory, and which we have previously argued cancels, we find that the 3/2 and 5/2 powers are also miraculously absent.

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Gianluca Grignani, Marta Orselli, Bojan Ramadanovic, Gordon W. Semenoff, Donovan Young. 2006-05-08. AdS/CFT v.s. String Loops. https://doi.org/10.1088/1126-6708%2F2006%2F06%2F040

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