{ "id": "1012.5201", "version": "v1", "published": "2010-12-23T13:48:59.000Z", "updated": "2010-12-23T13:48:59.000Z", "title": "Upper bounds for the number of zeroes for some Abelian integrals", "authors": [ "Armengol Gasull", "J. Tomás Lázaro", "Joan Torregrosa" ], "categories": [ "math.DS" ], "abstract": "Consider the vector field $x'= -yG(x, y), y'=xG(x, y),$ where the set of critical points $\\{G(x, y) = 0\\}$ is formed by $K$ straight lines, not passing through the origin and parallel to one or two orthogonal directions. We perturb it with a general polynomial perturbation of degree $n$ and study which is the maximum number of limit cycles that can bifurcate from the period annulus of the origin in terms of $K$ and $n.$ Our approach is based on the explicit computation of the Abelian integral that controls the bifurcation and in a new result for bounding the number of zeroes of a certain family of real functions. When we apply our results for $K\\le4$ we recover or improve some results obtained in several previous works.", "revisions": [ { "version": "v1", "updated": "2010-12-23T13:48:59.000Z" } ], "analyses": { "subjects": [ "34C08", "34C07", "34C23", "37C27" ], "keywords": [ "abelian integral", "upper bounds", "general polynomial perturbation", "period annulus", "orthogonal directions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1012.5201G" } } }