Searcharxiv⌕ Search

arXiv · nlin/0204053

Generalized Benney Lattice and the Heavenly Equation

Abstract

We generalize the Benney lattice and show that the new system of equations can be reduced to a generalized Chaplygin gas as well as the heavenly equation. We construct two infinite sets of conserved charges and show that one of the sets can be obtained from the Lax function. The conserved densities are related to Legendre polynomials and we present closed form expressions for the generating functions for these densities which also determines the Riemann invariants of the problem. We prove that the system is bi-Hamiltonian and that the conserved charges are in involution with respect to either of the Hamiltonian structures. We show that the associated generalized elastic medium equations are bi-Hamiltonian as well. We also bring out various other interesting features of our model.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A. Constandache, Ashok Das, Ziemowit Popowicz. 2002-04-22. Generalized Benney Lattice and the Heavenly Equation. https://arxiv.org/abs/nlin/0204053

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

The $\mathrm{al}_{ab}$ functions of hyperelliptic curves: a generalization of Jacobi's elliptic functions and explicit solutions of a degenerate Krichever-Novikov equation

The Jacobi elliptic functions $\mathrm{sn}$, $\mathrm{cn}$, $\mathrm{dn}$ and their ratios are expressed by Weierstrass's functions $\mathrm{al}_a=\sqrt{x-b_a}$ of an elliptic curve. For a hyperelliptic curve of genus $g$, Weierstrass's $\mathrm{al}_a$ functions generalize $\mathrm{sn}$, $\mathrm{cn}$ and $\mathrm{dn}$, and the modified Korteweg-de Vries and sine-Gordon equations stand behind them. In this paper we study the $\mathrm{al}_{ab}$ functions, which are defined by the sigma function shifted by the sum of two half-periods and which, together with the ratios of the $\mathrm{al}_a$ functions, generalize the remaining Jacobi elliptic functions. We determine the exact lattice of periods of $\mathrm{al}_{12}$ and show that it is single-valued on the unramified double covering of the Jacobian corresponding to the double covering $\hat{w}^2=(x-b_1)(x-b_2)$ of the curve. We show that $\mathrm{al}_{12}$ is the Wronskian of the band-edge eigenfunctions $\mathrm{al}_1$ and $\mathrm{al}_2$, so that the half-period translations realize Darboux transformations. As the main result, $\mathrm{al}_{12}$, $\mathrm{al}_2/\mathrm{al}_1$ and $1/\mathrm{al}_{12}$ satisfy one and the same degenerate Krichever-Novikov equation, whose polynomial has the double roots $0$ and $\infty$, and the half-periods act on these solutions as the Möbius symmetries of the equation. Thus the Krichever-Novikov equation stands behind the $\mathrm{al}_{ab}$ functions. In genus one these functions reduce to $\mathrm{sn}$, $\mathrm{ns}$ and $\mathrm{dc}$.

nlin.SI↗

The integer spectrum of a superintegrable quantum field theory

In our previous article CMP 407 (2026) 131, we explored the rich algebraic structures arising from a specific quantum many-body Hamiltonian quartic in the bosonic creation-annihilation operators. This Hamiltonian originated from the works of Gérard and Grellier on classical turbulent energy transfer in a Lax-integrable setting, and its quantum version respects hierarchies of polynomial conservation laws all of which possess purely integer spectra, as does the Hamiltonian itself. The latter feature, known from numerical studies, has previously remained unproved. Here, we present an elementary solution of the quantum Gérard-Grellier Hamiltonian. The eigenstates are labelled by partitions and the corresponding eigenvalues admit simple explicit expressions in terms of the principal hook lengths. The key ingredient in this construction is a specific basis we introduce, inspired by the classical multisoliton coherent states, in which the Hamiltonian is upper-triangular. The expressions for the eigenvalues then immediately follow, while the full eigenbasis can be recovered via a Gram-Schmidt procedure.

nlin.SI↗

The \texorpdfstring{$\mathbf N$-soliton}{N-soliton} solution formula for the Kaup--Kupershmidt equation

An explicit formula is presented for the $\mathbf N$-soliton solution to the Kaup--Kupershmidt equation, for any positive integer $\mathbf N,$ by using the input data set consisting of $\mathbf N$ distinct positive $p_j$-values and $\mathbf N$ arbitrarily chosen positive $c_j$-values. The formula is derived from the solution to the inverse scattering problem for a third-order linear operator in the reflectionless case with the $p_j$-values related to the bound-state poles of a transmission coefficient and the $c_j$-values related to the bound-state dependency constants. It is indicated how the formula is constructed from the solution to a Riemann--Hilbert problem and from the solution to a Marchenko integral equation used in the formulation of the aforementioned inverse scattering problem.

nlin.SI↗