collaborators

6 papers

nlin.SI2025

Liouvillian integrability of vector fields in higher dimensions

Waleed Aziz, Colin Christopher, Chara Pantazi +1

We consider complex rational vector fields in dimension (equivalently, differential forms of degree in variables) which admit a Liouvillian first integral. Extendin…

nlin.SI2025

Liouvillian integrability of three dimensional vector fields

Waleed Aziz, Colin Christopher, Chara Pantazi +1

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…

math.DS2025

On elementary integrability of rational vector fields

Colin Christopher, Sebastian Walcher

We consider complex rational vector fields that admit a first integral whose logarithmic derivative lies in a finite extension of the rational function field . In view of the Pr…

math.RA2025

Liouvillian integrability of rational vector fields: The case of algebraic extensions

Colin Christopher, Chara Pantazi, Sebastian Walcher

As shown in a previous paper, whenever a rational vector field on , , is Liouvillian integrable, then it admits a first integral obtained by two successive integr…

math.CO2025

Resnikoff silver numbers and tilings of the half-line (Dedicated to the memory of H.L.Resnikoff)

Josef F. Dorfmeister, Sebastian Walcher

Building on work by H.L.Resnikoff we consider (Resnikoff) silver numbers, which generalize the familiar golden number. By definition, a silver number is the largest positive root o…

math.DS2025

Poincarè-Dulac Normal Forms: Formal and Analytic Aspects

Valery G. Romanovski, Sebastian Walcher

We discuss various aspects concerning transformations of local analytic, or formal, vector fields to Poincarè-Dulac normal form, and the convergence of such transformations. After…