Multiparticle quasiexactly solvable difference equations

Abstract

Several explicit examples of multiparticle quasiexactly solvable “discrete” quantum mechanical Hamiltonians are derived by deforming the well-known exactly solvable multiparticle Hamiltonians, the Ruijsenaars-Schneider-van Diejen systems. These are difference analogs of the quasiexactly solvable multiparticle systems, the quantum Inozemtsev systems obtained by deforming the well-known exactly solvable Calogero-Sutherland systems. They have a finite number of exactly calculable eigenvalues and eigenfunctions. This paper is a multiparticle extension of the recent paper by one of the authors [R. Sasaki, J. Math. Phys. 48, 122104 (2007)] on deriving quasiexactly solvable difference equations of single degree of freedom.