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arXiv · hep-th/9808153

Bethe Equations "on the Wrong Side of Equator"

G. P. Pronko·Yu. G. Stroganov
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Abstract

We analyse the famous Baxter's $T-Q$ equations for $XXX$ ($XXZ$) spin chain and show that apart from its usual polynomial (trigonometric) solution, which provides the solution of Bethe-Ansatz equations, there exists also the second solution which should corresponds to Bethe-Ansatz beyond $N/2$. This second solution of Baxter's equation plays essential role and together with the first one gives rise to all fusion relations.

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G. P. Pronko, Yu. G. Stroganov. 1998-08-28. Bethe Equations "on the Wrong Side of Equator". https://doi.org/10.1088/0305-4470%2F32%2F12%2F007

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