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arXiv · 1304.7978

Algebraic Bethe ansatz for singular solutions

Rafael I. Nepomechie·Chunguang Wang
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Abstract

The Bethe equations for the isotropic periodic spin-1/2 Heisenberg chain with N sites have solutions containing i/2, -i/2 that are singular: both the corresponding energy and the algebraic Bethe ansatz vector are divergent. Such solutions must be carefully regularized. We consider a regularization involving a parameter that can be determined using a generalization of the Bethe equations. These generalized Bethe equations provide a practical way of determining which singular solutions correspond to eigenvectors of the model.

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Rafael I. Nepomechie, Chunguang Wang. 2013-04-30. Algebraic Bethe ansatz for singular solutions. https://doi.org/10.1088/1751-8113%2F46%2F32%2F325002

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