arXiv subjects

Waleed Aziz

Publications and source records attributed to Waleed Aziz.

5 recordsLinked to original sources

arXiv2025

Liouvillian integrability of vector fields in higher dimensions

We consider complex rational vector fields in dimension $n>2$ (equivalently, differential forms of degree $n-1$ in $n$ variables) which admit a Liouvillian first integral. Extending a classical result by Singer for $n=2$, our main result states that there exists a first integral which is obtained by two successive integrations from one-forms with coefficients in a finite algebraic extension of the rational function field. The proof uses Puiseux series in a novel way to simplify computations. We also apply this method to give elementary proofs of Singer's theorem for rational one-forms, and of the Prelle-Singer theorem on elementary integrability of rational vector fields.

nlin.SI↗

arXiv2023

Liouvillian integrability of three dimensional vector fields

We consider a three dimensional complex polynomial, or rational, vector field (equivalently, a two-form in three variables) which admits a Liouvillian first integral. We prove that there exists a first integral whose differential is the product of a rational 1-form with a Darboux function, or there exists a Darboux Jacobi multiplier. Moreover, we prove that Liouvillian integrability {in any dimension $n\geq 3$} always implies the existence of a first integral that is obtained by two successive integrations from one-forms with coefficients in a finite algebraic extension of the rational function field.

nlin.SI↗

arXiv2023

Integrability of a Family of Lotka--Volterra Three Species Biological System

The aim of this study is to analyze the integrability problem of Lotka--Volterra three species biological system. The system which considered in this work is a biological plausibility or a chemical model. The system has a complex dynamical behavior because it is chaotic system. We, first show that the system is a complete integrable when two of the involved parameters in the system are zero. Second, thorough invariant algebraic surfaces and exponential factors, the nonintegrability problems have been investigated. Particularly, we show the non-existence of polynomial, rational, formal series, and Darboux first integrals when parameters are strictly positive.

math.DS↗

arXiv2022

Integral Aspects of $(1:-3:1)$ Resonance Lotka--Volterra Equations with Nonstandard Analysis

In this paper the problems of integrable and linearizable Lotka-Volterra equations with $(\delta:-3 \delta:\delta)$-resonance are studied. The necessary conditions for both problems are obtained in the case when $\delta=1$ and it's sufficiency are proved. It is also shown that non-standard analysis has an important role in proving the sufficient integrable conditions in some cases. The non-standard analysis approaches have been used for both perturbed and unperturbed cases for integral aspects of the given system.

nlin.SI↗

arXiv2011

Local Integrability and Linearizability of Three-dimensional Lotka-Volterra Systems

We investigate the local integrability and linearizability of three dimensional Lotka-Volterra equations at the origin. Necessary and sufficient conditions for both integrability and linearizability are obtained for (1,-1,1), (2,-1,1) and (1,-2,1)-resonance. To prove sufficiency, we mainly use the method of Darboux with extensions for inverse Jacobi multipliers, and the linearizability of a node in two variables with power-series arguments in the third variable.

math.DS↗