On the period function of Lienard systems

Authors
Sabatini, M
Citation
M. Sabatini, On the period function of Lienard systems, J DIFF EQUA, 152(2), 1999, pp. 467-487
Citations number
23
Categorie Soggetti
Mathematics
Journal title
JOURNAL OF DIFFERENTIAL EQUATIONS
ISSN journal
00220396 → ACNP
Volume
152
Issue
2
Year of publication
1999
Pages
467 - 487
Database
ISI
SICI code
0022-0396(19990301)152:2<467:OTPFOL>2.0.ZU;2-O
Abstract
We study the period function T of a center O of a Lienard system. A suffici ent condition for the monotonicity of T, or for the isochronicity of O, is given. Such a condition is also necessary when f and g are analytic, and g is odd. In this case a characterization of isochronous centers of Lienard s ystems is given. Strict monotonicity and global monotonicity of T are also investigated. (C) 1999 Academic Press.