Quasi-Exactly-Solvable Many-Body Problems
  Explicit examples of quasi-exactly-solvable $N$-body problems on the line are presented. These are related to the hidden algebra $sl_N$, and they are of two types -- containing up to $N$ (infinitely-many eigenstates are known, but not all) and up to 6 body interactions only (a finite number of eigenstates is known). Both types degenerate to the Calogero model. 
A. Minzoni, M. Rosenbaum, A. Turbiner (UNAM, Mexico)