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arXiv · 0804.1047

Bound States, Yangian Symmetry and Classical r-matrix for the AdS5 x S5 Superstring

M de Leeuw
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Abstract

We show that the recently found S-matrices describing the scattering of two-particle bound states of the light-cone string sigma model on AdS5 x S5 are compatible with Yangian symmetry. In case the invariance with respect to the centrally extended su(2|2) algebra is not sufficient to fully specify the scattering matrix, the requirement of Yangian symmetry provides an alternative to the Yang-Baxter equation and leads to a complete, up to an overall phase, determination of the S-matrix. We then compare the semi-classical limit of the bound state S-matrices with the universal classical r-matrix by Beisert and Spill evaluated in the corresponding bound state representations and find perfect agreement.

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M de Leeuw. 2009-10-06. Bound States, Yangian Symmetry and Classical r-matrix for the AdS5 x S5 Superstring. https://doi.org/10.1088/1126-6708%2F2008%2F06%2F085

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