Non-hyperbolic closed characteristics on non-degenerate star-shaped hypersurfaces in ${\mathbf{R}}^{2n}$

Huagui Duan, Hui Liu, Yiming Long +1

In this paper, we prove that for every index perfect non-degenerate compact star-shaped hypersurface $\Sigma \subset {\mathbf{R}}^{2n}$, there exist at least $n$ non-hyperbolic closed characte…