Compactified isospectral sets of complex tridiagonal Hessenberg matrices

Completely integrable infinite-dimensional Hamiltonian and Lagrangian systems, integration methods, integrability tests, integrable hierarchies (KdV, KP, Toda, etc.) (37K10) Hermitian, skew-Hermitian, and related matrices (15B57) Completely integrable finite-dimensional Hamiltonian systems, integration methods, integrability tests (37J35) Relations of infinite-dimensional Hamiltonian and Lagrangian dynamical systems with algebraic geometry, complex analysis, and special functions (37K20) Completely integrable systems and methods of integration for problems in Hamiltonian and Lagrangian mechanics (70H06)