6 papers
Nonlinearization of bilinear equations of the sine-Gordon type, nonlinear Schrödinger type and Benjamin-Ono type
Jin Liu, Da-jun Zhang, Xin Zhang +1
This is a continuation of the paper [Commun. Theor. Phys., 77 (2025) 115006] on the nonlinearization of bilinear equations. The sine-Gordon type and nonlinear Schrödinger type bil…
-invariant integrable systems from factorisation of linear differential and difference operators
Frank Nijhoff, Linyu Peng, Cheng Zhang +1
In this paper, we present a unified approach to constructing continuous and discrete -invariant integrable systems, formulated in terms of the common dependent var…
Constraints of the DKP hierarchy to the semi-discrete AKNS and Burgers hierarchies
Jin Liu, Da-jun Zhang
The paper investigates three eigenfunction constraints of two (2+1)-dimensional differential-difference integrable systems. First, we revisit the known squared eigenfunction symmet…
On the formulation of the NQC variable
Leilei Shi, Cheng Zhang, Da-jun Zhang
The Nijhoff-Quispel-Capel (NQC) equation is a general lattice quadrilateral equation presented in terms of a function where and serve as extra parameters. It can b…
On the Dbar method and direct linearization approach of the lattice KdV type equations
Leilei Shi, Cheng Zhang, Da-jun Zhang
The purpose of this paper is to bridge the gap between the Dbar method and the direct linearization approach for the lattice Korteweg-de Vries (KdV) type equations. We develop the…
The elliptic lattice KdV system revisited
Frank Nijhoff, Cheng Zhang, Da-jun Zhang
In a previous paper [Nijhoff,Puttock,2003], a 2-parameter extension of the lattice potential KdV equation was derived, associated with an elliptic curve. This comprises a rather co…