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.
@article{arxiv.hep-th/9808153,
title = {Bethe Equations "on the Wrong Side of Equator"},
author = {G. P. Pronko and Yu. G. Stroganov},
journal= {arXiv preprint arXiv:hep-th/9808153},
year = {2008}
}
Comments
13 pages, original paper was spoiled during transmission