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arXiv · hep-th/0310252

The su(2|3) Dynamic Spin Chain

Niklas Beisert
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Abstract

The complete one-loop, planar dilatation operator of the N=4 superconformal gauge theory was recently derived and shown to be integrable. Here, we present further compelling evidence for a generalisation of this integrable structure to higher orders of the coupling constant. For that we consider the su(2|3) subsector and investigate the restrictions imposed on the spin chain Hamiltonian by the symmetry algebra. This allows us to uniquely fix the energy shifts up to the three-loop level and thus prove the correctness of a conjecture in hep-th/0303060. A novel aspect of this spin chain model is that the higher-loop Hamiltonian, as for N=4 SYM in general, does not preserve the number of spin sites. Yet this dynamic spin chain appears to be integrable.

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Niklas Beisert. 2003-12-09. The su(2|3) Dynamic Spin Chain. https://doi.org/10.1016/j.nuclphysb.2003.12.032

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