科研之友
微信
新浪微博
Facebook
分享链接
摘要
Let X be a Banach space and let T : X -> X be a power bounded linear operator. Put X(0) = {x is an element of X | T(n)x -> 0}. Assume given a compact set K subset of X such that lim inf(n ->infinity)rho{T(n)x, K} <= eta < 1 for every x is an element of X, ||x|| <= 1. If eta < 1/2, then codim X(0) < infinity. This is true in X reflexive for eta is an element of [1/2, 1), but fails in the general case.
- 出版日期2011-11
