A Preparation Theorem for a Class of Non-differentiable Functions with an Application to Hilbert's 16th Problem

Affiliation auteursAffiliation ok
TitreA Preparation Theorem for a Class of Non-differentiable Functions with an Application to Hilbert's 16th Problem
Type de publicationBook Chapter
Year of Publication2016
AuteursMorsalani MEl, Mourtada A
EditorToni B
Book TitleMATHEMATICAL SCIENCES WITH MULTIDISCIPLINARY APPLICATIONS: IN HONOR OF PROFESSOR CHRISTIANE ROUSSEAU. AND IN RECOGNITION OF THE MATHEMATICS FOR PLANET EARTH INITIATIVE
Series TitleSpringer Proceedings in Mathematics & Statistics
Volume157
Pagination133-177
PublisherSPRINGER
City233 SPRING STREET, NEW YORK, NY 10013, UNITED STATES
ISBN Number978-3-319-31323-8; 978-3-319-31321-4
ISBN2194-1009
Mots-clésChebychev expansion, Hilbert 16th problem, Hyperbolic saddle point, Malgrange preparation theorem, Pseudo-isomorphism, Quasi-regular function
Résumé

We consider a class of unfoldings of quasi-regular functions. We assume that such perturbations have asymptotic developments which depend on many unfoldings of the logarithm function. We prove a preparation theorem for such functions; namely, they are ``conjugated'' to a finite principal part via a ``pseudoisomorphism''. This finite principal part is polynomial in the phase variable and these unfoldings of the logarithm function. As an application there exists a uniform bound in the parameter of the numbers of zeros of such class of non-differentiable functions. A finiteness result of the number of the limit cycles bifurcating from a perturbed hyperbolic polycycle is obtained too.

DOI10.1007/978-3-319-31323-8_8