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Completeness of the Bethe ansatz for the six and eight-vertex models

R. J. Baxter
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Abstract

We discuss some of the difficulties that have been mentioned in the literature in connection with the Bethe ansatz for the six-vertex model and XXZ chain, and for the eight-vertex model. In particular we discuss the ``beyond the equator'', infinite momenta and exact complete string problems. We show how they can be overcome and conclude that the coordinate Bethe ansatz does indeed give a complete set of states, as expected.

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R. J. Baxter. 2002-02-07. Completeness of the Bethe ansatz for the six and eight-vertex models. https://arxiv.org/abs/cond-mat/0111188

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