Journal of Nonlinear Mathematical Physics

Volume 25, Issue 3, July 2018
Letter to Editor

1. On nonlinearity in three-dimensional equatorial flows

David Henry
Pages: 351 - 357
We examine an aspect of the modelling of the underlying fluid motion in the equatorial region of the ocean. In particular, we assess whether nonlinearity is inherently vital in capturing the three-dimensional upwelling and downwelling phenomena. A recent applied mathematical approach has successfully...
Research Article

2. Invariant functions and contractions of certain types of Lie algebras of lower dimensions

J.M. Escobar, J. Núñez, P. Pérez-Fernández
Pages: 358 - 374
In this paper, we deal with contractions of Lie algebras. We use two invariant functions of Lie algebras as a tool, named ψ and φ function, respectively, which have a great application in Physics due to their remarkable properties. We focus the study of these functions in the frame of the filiform Lie...
Research Article

3. Supersymmetric Sawada-Kotera Equation: Bäcklund-Darboux Transformations and Applications

Hui Mao, Q.P. Liu, Lingling Xue
Pages: 375 - 386
In this paper, we construct a Darboux transformation and the related Bäcklund transformation for the super-symmetric Sawada-Kotera (SSK) equation. The associated nonlinear superposition formula is also worked out. We demonstrate that these are natural extensions of the similar results of the Sawada-Kotera...
Research Article

4. Integrability Conditions for Complex Homogeneous Kukles Systems

Jaume Giné, Claudia Valls
Pages: 387 - 398
In this paper we study the existence of local analytic first integrals for complex polynomial differential systems of the form ẋ = x + Pn(x, y), ẏ = −y, where Pn(x,y) is a homogeneous polynomial of degree n, called the complex homogeneous Kukles systems of degree n. We characterize all the homogeneous...
Research Article

5. The description of reflection coefficients of the scattering problems for finding solutions of the Korteweg–de Vries equations

Pham Loi Vu
Pages: 399 - 432
The results of inverse scattering problem associated with the initial-boundary value problem (IBVP) for the Korteweg–de Vries (KdV) equation with dominant surface tension are formulated. The necessary and sufficient conditions for given functions to be the left- and right-reflection coefficients of the...
Research Article

6. Finite and infinite systems of nonlinearly-coupled ordinary differential equations, the solutions of which feature remarkable Diophantine findings

Francesco Calogero
Pages: 433 - 441
We use previous results concerning the time evolution of the zeros xn(t) of time-dependent polynomials pN(z; t) or entire functions F(z; t) of the complex variable z, in order to identify lots of nonlinearly-coupled, finite or infinite, systems of Ordinary Differential Equations the solutions of which...
Research Article

7. Pseudo-Hermitian Reduction of a Generalized Heisenberg Ferromagnet Equation. II. Special Solutions

T. I. Valchev, A. B. Yanovski
Pages: 442 - 461
This paper is a continuation of our previous work in which we studied a sl(3, ℂ) Zakharov-Shabat type auxiliary linear problem with reductions of Mikhailov type and the corresponding integrable hierarchy of nonlinear evolution equations. Now, we shall demonstrate how one can construct special solutions...
Research Article

8. Hopf magnetic curves in the anti-de Sitter space 𝔿13

Giovanni Calvaruso, Marian Ioan Munteanu
Pages: 462 - 484
We consider the anti-de Sitter space 𝔿13 and the hyperbolic Hopf fibration h:𝔿13(1)→𝔿2(1/2). Using their description in terms of paraquaternions, we study the magnetic curves of the hyperbolic Hopf vector field. A complete classification is obtained for light-like magnetic curves, showing in particular...
Research Article

9. The number of independent Traces and Supertraces on the Symplectic Reflection Algebra H1,η(Γ ≀ SN)

S.E. Konstein, I.V. Tyutin
Pages: 485 - 496
Symplectic reflection algebra H1,η(G) has a T(G)-dimensional space of traces whereas, when considered as a superalgebra with a natural parity, it has an S(G)-dimensional space of supertraces. The values of T(G) and S(G) depend on the symplectic reflection group G and do not depend on the parameter η. In...
Research Article

10. Further Riccati Differential Equations with Elliptic Coefficients and Meromorphic Solutions

Adolfo Guillot
Pages: 497 - 508
We exhibit some families of Riccati differential equations in the complex domain having elliptic coefficients and study the problem of understanding the cases where there are no multivalued solutions. We give criteria ensuring that all the solutions to these equations are meromorphic functions defined...