The department calendar is might be out sick today*, so I figured I would pass along the announcement for topology seminar today.
We are very excited to have Andy speak. His title and abstract are below:
Title: CAT(0) Extensions of Right-angled Coxeter Groups
Abstract: CAT(0) spaces are spaces that model non-negatively curved behavior, and CAT(0) groups are those that act on such spaces in a sufficiently nice way. The CAT(0) property is not known to be preserved by abstract commensurability. Right angled Coxeter groups (RACGs) are an important class of examples with a variety
of nice geometric, algebraic and algorithmic properties. I’ll discuss joint work with Charles Cunningham, Adam Piggott, and Kim Ruane in which we show that certain split extensions of RACGs are CAT(0), but for very different reasons depending on the type of extension. Time permitting, I’ll mention some interesting extensions for which the CAT(0) property has not been proved or disproved. This talk will be entirely accessible for grad students; I’ll give all necessary background.
* At least for my mac with OSX 10.11.6 and google chrome Version 60.0.3112.101.
______________________
Neil R. Hoffman
Assistant Professor
Department of Mathematics
523 Math Science Building
Oklahoma State University
Stillwater, OK 74078-1058
405-744-7791
http://math.okstate.edu/people/nhoffman
