On a conjecture on the integrability of Liénard systems

We consider the Liénard differential systems ̇x=y+F(x), ̇y=x (1), in C2 where F(x) is an analytic function satisfying F(0) = 0 and F'(0) ≠ 0. Then these systems have a strong saddle at the origin of coordinates. It has been conjecture that if such systems have an analytic first integral defined...

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Detalles Bibliográficos
Autores: Llibre, Jaume|||0000-0002-9511-5999, Murza, Adrian|||0000-0001-9521-5052, Valls, Clàudia|||0000-0001-8279-1229
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:221375
Acceso en línea:https://ddd.uab.cat/record/221375
https://dx.doi.org/urn:doi:10.1007/s12215-018-00398-6
Access Level:acceso abierto
Palabra clave:Liénard system
First integral
Strong saddle
Descripción
Sumario:We consider the Liénard differential systems ̇x=y+F(x), ̇y=x (1), in C2 where F(x) is an analytic function satisfying F(0) = 0 and F'(0) ≠ 0. Then these systems have a strong saddle at the origin of coordinates. It has been conjecture that if such systems have an analytic first integral defined in a neighborhood of the origin, then the function F(x) is linear, i.e. F(x) = ax. Here we prove this conjecture, and show that when F(x) is linear and system (1) has an analytic first integral, this is a polynomial.