ATTENTION : salle inhabituelle / unusual room

We review some exact results for the XXZ spin chain obtained recently. We begin with a general discussion of the XXZ spin chain and the Bethe ansatz method. Then the connection with the six-vertex statistical model is established and the Baxter T-Q equation is introduced. An exact special solution of the Baxter T-Q equation is obtained. It is argued that this solution corresponds to the ground state of the XXZ spin chain with the anisotropy parameter equal to -1/2. Some conjectured and proved results on the state under consideration are given. The most of them are related to enumerations of the alternating-sign matrices.


(Séminaire de la Fédération de Physique Statistique Paris-Sud)

IHEP, Protvino, Russia