Unraveling hidden hierarchies and dual structures in an integrable field   model
  An integrable field theory, due to path-independence on the space-time plane, should yield together with an infinite set of independent conserved charges also similar dual charges determining the boundary and defect contributions. On the example of the nonlinear Schroedinger equation we unravel hidden hierarchies and dual structures and show the complete integrability through a novel Yang-Baxter equation at the classical and quantum level with exact solution. 
Anjan Kundu
nlin.SI cond-mat.stat-mech hep-th math-ph math.MP