대수적 베테 가설 풀이(algebraic Bethe ansatz)
하이젠베르크 XXX 스핀 체인 모형
$\begin{eqnarray} \left[ B(\lambda), B(\lambda') \right] \ &=& 0 \\ A(\lambda)\ B(\lambda') &=& {a(\lambda' - \lambda)\over b(\lambda' - \lambda)} B(\lambda')\ A(\lambda) - {c(\lambda' - \lambda)\over b(\lambda' - \lambda)} B(\lambda)\ A(\lambda') \\ D(\lambda)\ B(\lambda') &=& {a(\lambda - \lambda')\over b(\lambda - \lambda')}B(\lambda')\ D(\lambda) - {c(\lambda - \lambda')\over b(\lambda - \lambda')} B(\lambda)\ D(\lambda') \end{eqnarray}$