The Bi-Hamiltonian Structure of the Short Pulse Equation

We prove the integrability of the short pulse equation derived recently by Sch\"afer and Wayne from a hamiltonian point of view. We give its bi-hamiltonian structure and show how the recursion operator defined by the hamiltonian operators is connected with the one obtained by Sakovich and Sakovich. An alternative zero-curvature formulation is also given.Comment: Latex file, 7 pages, to appear in Physics Letter

Dispersionless Fermionic KdV

We analyze the dispersionless limits of the Kupershmidt equation, the SUSY KdV-B equation and the SUSY KdV equation. We present the Lax description for each of these models and bring out various properties associated with them as well as discuss open questions that need to be addressed in connection with these models.Comment: 15 page

Dispersionless sTB

We analyze the dispersionless limits of the SUSY TB-B (sTB-B) and the SUSY TB (sTB) hierarchies. We present the Lax description for each of these models, as well as the N=2 sTB hierarchy and bring out various properties associated with them. We also discuss open questions that need to be addressed in connection with these models.Comment: Latex 15 page

Supersymmetric Extensions of the Harry Dym Hierarchy

We study the supersymmetric extensions of the Harry Dym hierarchy of equations. We obtain the susy-B extension, the doubly susy-B extension as well as the N=1 and the N=2 supersymmetric extensions for this system. The N=2 supersymmetric extension is particularly interesting, since it leads to new classical integrable systems in the bosonic limit. We prove the integrability of these systems through the bi-Hamiltonian formulation of integrable models and through the Lax description. We also discuss the supersymmetric extension of the Hunter-Zheng equation which belongs to the Harry Dym hierarchy of equations.Comment: 15 pages, Latex fil

Dispersionless Limit of Integrable Models

Nonlinear dispersionless equations arise as the dispersionless limit of well know integrable hierarchies of equations or by construction, such as the system of hydrodynamic type. Some of these equations are integrable in the Hamiltonian sense and appear in the study of topological minimal models. In the first part of the review we will give a brief introduction to integrable models, mainly its Lax representation. Then, we will introduce the dispersionless limit and show some of our results concerning the two-component hyperbolic system of equations such as the polytropic gas and Born-Infeld equations.Comment: 25 pages, 4 figures, Te

Hamiltonian Structures for the Generalized Dispersionless KdV Hierarchy

We study from a Hamiltonian point of view the generalized dispersionless KdV hierarchy of equations. From the so called dispersionless Lax representation of these equations we obtain three compatible Hamiltonian structures. The second and third Hamiltonian structures are calculated directly from the r-matrix approach. Since the third structure is not related recursively with the first two ones the generalized dispersionless KdV hierarchy can be characterized as a truly tri-Hamiltonian system.Comment: 16 pages, plain Te

The sTB-B Hierarchy

We construct a new supersymmetric two boson (sTB-B) hierarchy and study its properties. We derive the conserved quantities and the Hamiltonian structures (proving the Jacobi identity) for the system. We show how this system gives the sKdV-B equation and its Hamiltonian structures upon appropriate reduction. We also describe the zero curvature formulation of this hierarchy both in the superspace as well as in components.Comment: 15 pages, Te