Stability of closed characteristics on compact convex hypersurfaces in
arXiv:math/0701673
Abstract
In this paper, let be a compact convex hypersurface. We prove that if carries only finitely many geometrically distinct closed characteristics, then at least two of them must possess irrational mean indices. Moreover, if $\Sg$ carries exactly three geometrically distinct closed characteristics, then at least two of them must be elliptic.
24 pages, to appear in J. Eur. Math. Soc