Polynomial differential systems with invariant algebraic curves of arbitrary degree formed by Legendre polynomials

In 1891 Poincaré asked: Given m ≥ 2, is there a positive integer M(m) such that if a polynomial differential system of degree m has an invariant algebraic curve of degree ≥ M(m), then it has a rational first integral? Brunella and Mendes repeated the same open question in 2000, and Lins-Neto in 2002...

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Detalles Bibliográficos
Autores: Llibre, Jaume|||0000-0002-9511-5999, Valls, Clàudia|||0000-0001-8279-1229
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:318295
Acceso en línea:https://ddd.uab.cat/record/318295
https://dx.doi.org/urn:doi:10.1016/j.jpaa.2025.108001
Access Level:acceso embargado
Palabra clave:Polynomial differential systems
Invariant algebraic curve
Rational first integral
Hermite polynomials
Laguerre polynomials
Legendre polynomials
Descripción
Sumario:In 1891 Poincaré asked: Given m ≥ 2, is there a positive integer M(m) such that if a polynomial differential system of degree m has an invariant algebraic curve of degree ≥ M(m), then it has a rational first integral? Brunella and Mendes repeated the same open question in 2000, and Lins-Neto in 2002. Between the years 2001 and 2003 three different families of quadratic polynomial differential systems provided a negative answer to this question. One of the answers used the Hermite polynomials. Recently a new negative answer was provided for polynomial differential systems of arbitrary degree using the Laguerre polynomials. In this paper we provide another new negative answer but using for first time the Legendre polynomials. So the orthogonal polynomials play a role in the Poincaré's question. Moreover we classify the phase portraits of these polynomial differential systems having invariant algebraic curves of arbitrary degree based on the Legendre polynomials.