For one dimensional SU(n) Hubbard model, a pair of Lax operators are derived, which give a set of fundamental equations for the quantum inverse scattering method under both periodic and open boundary conditions. This provides another proof of the integrability of the model under periodic boundary condition. PACS Numbers: 46.10.+z, 05.40.+j, 05.60.+w e-mail: [email protected] Integrable strong...

— In this paper we give an algorithmic method of deriving the Lax pair for the modified Korteweg-de Vries hierarchy. For each n, the compatibility condition gives the n-th member of the hierarchy, rather than its derivative. A direct consequence of this is that we obtain the isomonodromy problem for the second Painlevé hierarchy, which is derived through a scaling reduction. Résumé (La paire de...

The dependence of the sixth equation of Painlevé on its four parameters (2α,−2β, 2γ, 1− 2δ) = (θ ∞ , θ 0 , θ 2 1 , θ 2 x) is holomorphic, therefore one expects all its Lax pairs to display such a dependence. This is indeed the case of the second order scalar “Lax” pair of Fuchs, but the second order matrix Lax pair of Jimbo and Miwa presents a meromorphic dependence on θ∞ (and a holomorphic dep...

The use of Lax pair tensors as a unifying framework for Killing tensors of arbitrary rank is discussed. Some properties of the tensorial Lax pair formulation are stated. A mechanical system with a wellknown Lax representation – the three-particle open Toda lattice – is geometrized by a suitable canonical transformation. In this way the Toda lattice is realized as the geodesic system of a certai...

A typical and effective way to construct a higher dimensional integrable equation is to extend the Lax pair for a (1 + 1) dimensional equation known as integrable to higher dimensions. Here we construct an alternative modified KdV equation in (2+1) dimensions by the higherdimensional extension of a Lax pair. And it is shown that this higher dimensional modified KdV equation passes the Painlevé ...

— We discuss a local reduction theorem for 0-parameter solutions of a higher order Painlevé equation and its underlying Lax pair near a simple turning point of the first kind when the size of the Lax pair is greater than 2. As a typical example of such higher order Painlevé equations the Noumi-Yamada systems are mainly considered. Résumé (Sur une réduction locale au voisinage d’un point tournan...

There is a wide class of integrable Hamiltonian systems on finite-dimensional coadjoint orbits of the loop algebra g̃l(r) which are represented by r × r Lax equations with a rational spectral parameter. A reduced complex phase space is foliated with open subsets of Jacobians of regularized spectral curves. Under some generic restrictions on the structure of the Lax matrix, we propose an algebrai...

The purpose of this talk will be to present a new reduced-order modelling approach to solve nonlinear evolution partial differential equations. It is based on approximations of generalized Lax pairs. Contrary to other reduced-order methods, the basis on which the solution is searched for evolves in time according to a dynamics specific to the problem. It is therefore well-suited to solving prob...

which was discovered in a symmetry classification of nonlocal PDEs with quadratic or cubic nonlinearity. By using the perturbation symmetry approach [7], Novikov found the first few symmetries and a scalar Lax pair for Eq. (1), then proved that it is integrable [9]. Hone and Wang [5] gave a matrix Lax pair for the Novikov equation and found its infinitely many conserved quantities, as well as a...