题目：Smooth invariant manifolds and foliations without a spectral gap
报告人：张文萌（重庆师范大学）
时间：2018年6月20日16:00-17:00
地点：恩明楼813
摘要：It is known that a spectral gap condition is required for the existence and smoothness of invariant manifolds and invariant foliations near a fixed point. However, any planar mapping with a unipotent linear part, having a center manifold on the whole phase plane, does not have such a gap. In this talk, we give the existence and smoothness of invariant manifolds, which are invariant submanifolds of the center manifold, for the aforementioned planar mapping. Corresponding to the invariant submanifolds, we further give the existence and smoothness of invariant foliations on the center manifold.