Jaros\l aw G\'ornicki
Fixed points of asymptotically regular mappings in spaces with uniformly normal structure

Comment.Math.Univ.Carolinae 32,4 (1991) 639-643.

Abstract:It is proved that: for every Banach space $X$ which has uniformly normal structure there exists a $k>1$ with the property: if $A$ is a nonempty bounded closed convex subset of $X$ and $T:A\rightarrow A$ is an asymptotically regular mapping such that $$ \liminf _{n\rightarrow \infty } |||T_n|||< k, $$ where $|||T|||$ is the Lipschitz constant (norm) of $T$, then $T$ has a fixed point in $A$.

Keywords: asymptotically regular mappings, uniformly normal structure, fixed points
AMS Subject Classification: 47H10

PDF