Yangian symmetry and Virasoro character in a lattice spin system with long-range interactions Original Research Article

We consider the symmetry of lattice su(n) spin systems with inverse square exchange; the Haldane-Shastry model and the Polychronakos-Frahm model. It is shown that both systems have yangian symmetry for a finite number of sites. Based on the yangian symmetry the energy spectrum is considered. Furthermore the representation for motifs and the relations with the Virasoro character for su(n) level-1 Wess-Zumino- Witten theory are discussed.