Centers for the Kukles homogeneous systems with odd degree

For the polynomial differential system x˙ = −y, y˙ = x+Qn(x; y), where Qn(x; y) is a homogeneous polynomial of degree n there are the following two conjectures done in 1999. (1) Is it true that the previous system for n ≥ 2 has a center at the origin if and only if its vector field is symmetric abou...

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Detalles Bibliográficos
Autores: Giné, Jaume, Llibre, Jaume, Valls, Claudia
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10459.1/58395
Acceso en línea:https://doi.org/10.1112/blms/bdv005
http://hdl.handle.net/10459.1/58395
Access Level:acceso abierto
Palabra clave:Integrability
Complex center-focus problem
Lyapunov constants
Bautin method
Matemàtica
Mathematics
Descripción
Sumario:For the polynomial differential system x˙ = −y, y˙ = x+Qn(x; y), where Qn(x; y) is a homogeneous polynomial of degree n there are the following two conjectures done in 1999. (1) Is it true that the previous system for n ≥ 2 has a center at the origin if and only if its vector field is symmetric about one of the coordinate axes? (2) Is it true that the origin is an isochronous center of the previous system with the exception of the linear center only if the system has even degree? We prove both conjectures for all n odd.