Thursday, September 14, 2000
| Title |
Turing's Famous Leopards' Spots Problem |
| Speaker |
Professor Richard Stark |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Thursday, September 28, 2000
| Title |
Turing's Famous Leopards' Spots Problem, II |
| Speaker |
Professor Richard Stark |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Thursday, October 6, 2000
| Title |
Turing's Famous Leopards' Spots Problem, III |
| Speaker |
Professor Richard Stark |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Thursday, October 19, 2000
| Title |
Topological Entropy of Shift Spaces |
| Speaker |
Jamie Oberste-Vorth |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Abstract
In this talk I'll present the definition of entropy for compact metrizable spaces then prove a theorem which enables the entropy to be more easily computed for shift spaces over the integers. Then I'll expand the theorem to include shift spaces over \(Z\times Z\). Finally, I'll include some information about the entropy of shift spaces over some other groups.
Thursday, October 26, 2000
| Title |
Topological Entropy of Shift Spaces, II |
| Speaker |
Jamie Oberste-Vorth |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Thursday, November 2, 2000
| Title |
The Rigidity Question for Coxeter Groups |
| Speaker |
Dr. Anton Kaul |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Abstract
Coxeter groups are often defined as those having a presentation in which generators have order 2 and all other relations involve only pairs of generators. From a geometric standpoint it is preferable to define Coxeter groups as those that act “by reflections” on some topological space. It turns out that these two definitions are equivalent.
We will discuss the basic definitions and results on Coxeter groups, focusing on the geometric aspects. In particular we will see that any Coxeter group acts by isometries on a complete CAT(0) space (i.e., a metric space of non-positive curvature in the sense of Gromov) called the Davis complex.
The geometry of the Davis complex facilitates a topological approach to the “rigidity question” for Coxeter groups (a Coxeter group \(W\) is rigid if, given any two generating sets \(S\) and \(S'\) for \(W\), there is an automorphism of \(W\) which carries \(S\) to \(S'\)).
Thursday, November 9, 2000
| Title |
The Rigidity Question for Coxeter Groups, II |
| Speaker |
Dr. Anton Kaul |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Thursday, November 16, 2000
| Title |
The Rigidity Question for Coxeter Groups, III |
| Speaker |
Dr. Anton Kaul |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |
Thursday, November 30, 2000
| Topic |
Discrete Mathematics Program Development |
| Time |
12:00-01:00 p.m. |
| Place |
First Watch Restaurant |
Thursday, December 7, 2000
| Topic |
Discrete Mathematics Program Development, II |
| Time |
12:00-01:00 p.m. |
| Place |
PHY 108 |