Periodic orbits in complex Abel equation

This paper is devoted to prove two unexpected properties of the Abel equation dz/dt = z 3 +B(t)z 2 +C(t)z, where B and C are smooth, 2π-periodic complex valuated functions, t ∈ R and z ∈ C. The first one is that there is no upper bound for its number of isolated 2π-periodic solutions. In contrast, r...

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Detalles Bibliográficos
Autores: Cimà, Anna|||0000-0003-0256-518X, Gasull, Armengol|||0000-0002-1719-8231, Mañosas, Francesc|||0000-0003-2535-0501
Tipo de recurso: artículo
Fecha de publicación:2006
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:44203
Acceso en línea:https://ddd.uab.cat/record/44203
Access Level:acceso abierto
Palabra clave:Equacions abelianes
Cicles límits
Pertorbació (Matemàtica)
Dinàmica combinatòria
Descripción
Sumario:This paper is devoted to prove two unexpected properties of the Abel equation dz/dt = z 3 +B(t)z 2 +C(t)z, where B and C are smooth, 2π-periodic complex valuated functions, t ∈ R and z ∈ C. The first one is that there is no upper bound for its number of isolated 2π-periodic solutions. In contrast, recall that if the functions B and C are real valuated then the number of complex 2π-periodic solutions is at most three. The second property is that there are examples of the above equation with B and C being low degree trigonometric polynomials such that the center variety is formed by infinitely many connected components in the space of coefficients of B and C. This result is also in contrast with the characterization of the center variety for the examples of Abel equations dz/dt = A(t)z 3 + B(t)z 2 studied in the literature, where the center variety is located in a finite number of connected components.