Elliptic and non-hyperbolic closed characteristics on compact convex P-cyclic symmetric hypersurfaces in ${\mathbf{R}}^{2n}$

Hui Liu, Chongzhi Wang, Duanzhi Zhang

Let $\Sigma$ be a compact convex hypersurface in ${\mathbf{R}}^{2n}$ which is P-cyclic symmetric, i.e., $x\in \Sigma$ implies $Px\in \Sigma$ with P being a $2n\times 2n$ symplectic orthogonal matrix and…