Uniqueness of the limit cycles for complex differential equations with two monomials

We prove that any complex differential equation with two monomials of the form z˙ = azk ¯zl + bzm¯zn, with k, l, m, n non-negative integers and a, b ∈ C, has one limit cycle at most. Moreover, we characterise when such a limit exists and prove that then it is hyperbolic. For an arbitrary equation of...

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Detalles Bibliográficos
Autores: Álvarez Torres, María Jesús|||0000-0002-8046-8775, Gasull, Armengol|||0000-0002-1719-8231, Prohens, Rafel|||0000-0003-1184-6311
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:267124
Acceso en línea:https://ddd.uab.cat/record/267124
https://dx.doi.org/urn:doi:10.1016/j.jmaa.2022.126663
Access Level:acceso abierto
Palabra clave:Polynomial differential equation
Uniqueness of limit cycles
Centre-focus problem
Descripción
Sumario:We prove that any complex differential equation with two monomials of the form z˙ = azk ¯zl + bzm¯zn, with k, l, m, n non-negative integers and a, b ∈ C, has one limit cycle at most. Moreover, we characterise when such a limit exists and prove that then it is hyperbolic. For an arbitrary equation of the above form, we also solve the centrefocus problem and examine the number, position, and type of its critical points. In particular, we prove a Berlinski˘ı-type result regarding the geometrical distribution of the critical points stabilities.