Seminar series
Date
Tue, 13 May 2014
Time
17:00 -
18:00
Location
C5
Speaker
Eric Swenson
Organisation
Brigham Young
Let $A$ and $B$ be boundaries of CAT(0) spaces. A function $f:A \to B$ is called a {\em boundary isomorphism} if $f$ is a homeomorphism in the visual topology and
$f$ is an isometry in the Tits metric. A compact metrizable space $Y$ is said to be {\em Tits rigid}, if for any two CAT(0) group boundaries $Z_1$ and $Z_2$ homeomorphic to $Y$, $Z_1$ is boundary isomorphic to $Z_2$.
We prove that the join of two Cantor sets and its suspension are Tits rigid.