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arXiv · hep-th/9807065

Duality and quantum-algebra symmetry of the A_{N-1}^(1) open spin chain with diagonal boundary fields

Anastasia Doikou·Rafael I. Nepomechie
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Abstract

We show that the transfer matrix of the A_{N-1}^(1) open spin chain with diagonal boundary fields has the symmetry U_q (SU(L)) x U_q (SU(N-L)) x U(1), as well as a ``duality'' symmetry which interchanges L and N - L. We exploit these symmetries to compute exact boundary S matrices in the regime with q real.

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Anastasia Doikou, Rafael I. Nepomechie. 1998-07-09. Duality and quantum-algebra symmetry of the A_{N-1}^(1) open spin chain with diagonal boundary fields. https://doi.org/10.1016/s0550-3213(98)00567-7

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