| DATE | SEMINAR | SPEAKER | TITLE |
| Tues. Sept. 9 | Comp. Sci., 4:10-5:00 RH316 | Michael Goldwasser | Admission Control Problems, I |
| Thurs. Sept. 11 | Algebra, 2:00-3:00 RH222 | Greg Marks | On annelidan rings, I |
| Thurs. Sept. 11 | Topology, 3:45-4:45 RH134 | John Cantwell | Foliation Cones, I |
| Tues. Sept. 16 | Comp. Sci., 4:10-5:00 RH316 | Michael Goldwasser | Admission Control Problems, II |
| Thurs. Sept. 18 | Algebra, 2:00-3:00 RH222 | Greg Marks | On annelidan rings, II |
| Thurs. Sept. 18 | Topology, 3:45-4:45 RH134 | John Cantwell | Foliation Cones, II |
| Thurs. Sept. 25 | Algebra, 2:00-3:00 RH222 | Greg Marks | On annelidan rings, III |
| Thurs. Sept. 25 | Topology, 3:45-4:45 RH134 | Ian Agol, UIC | Ricci Flow (and Perelman's work on Thurston's Geometrization Conjecture) |
| Fri. Sept. 26 | Analysis, 1:00-2:00 RH109 | Brad Currey | Canonical coordinates for coadjoint orbits of solvable Lie groups |
| Tues. Sept. 30 | Grad Student, 2:10-3:00 RH142 | Christine Stevens | Why are mathematicians obsessed with proofs? |
| Abstract:What do you mean, "obsessed"? Mathematicians are just very careful about justifying everything they say, and they've always been that way, right? Well, maybe so, but maybe not. In this talk we will discuss when, how,
and why mathematical proofs began to take the form that they have today. You got a problem with that? This talk is aimed at anyone who has ever struggled to write a mathematical proof. No specific mathematical knowledge is assumed beyond a familiarity
with sets. |
| Tues. Sept. 30 | Comp. Sci., 4:10-5:00 RH316 | David Letscher | Introduction to Computational Geometry |
| Thurs. Oct. 2 | Algebra, 2:00-3:00 RH222 | Greg Marks | On annelidan rings, IV |
| Thurs. Oct. 2 | Topology, 3:45-4:45 RH134 | Anneke Bart | The deformation theory of the Bianchi groups |
| Tues. Oct. 7 | Comp. Sci., 4:10-5:00 RH316 | David Letscher | Introduction to Computational Geometry, II |
| Thurs. Oct. 9 | Algebra, 2:00-3:00 RH222 | Greg Marks | On annelidan rings, V |
| Tues. Oct. 14 | Comp. Sci., 4:10-5:00 RH316 | David Letscher | Introduction to Computational Geometry, III |
| Thurs. Oct. 16 | Algebra, 2:00-3:00 RH222 | Greg Marks | On annelidan rings, VI |
| Fri. Oct. 17 | Analysis, 1:00-2:00 RH109 | Brody Johnson | Finite-dimensional frames and the frame potential |
| Abstract:
The talk will present some
recent work by John Benedetto and Matthew Fickus
and would be fairly accessible to graduate
students.
|
| Thurs. Oct. 23 | Topology, 3:45-4:45 RH134 | José L. Flores, Universidad de Granada | On the geometry of gravitational waves |
| Tues. Oct. 28 | Comp. Sci., 4:10-5:00 RH316 | Kevin Scannell | From Eugene Onegin to a Maori grammar checker: a survey of statistical natural language processing, I |
| Abstract:
I will discuss
(1) The main goals of natural language processing;
(2) Hidden Markov models: what they are, how they help,
and how they are implemented;
(3) Techniques for building and exploiting large text
corpora, both monolingual and multilingual.
I won't assume any knowledge of computer science,
statistics, or linguistics.
|
| Thurs. Oct. 30 | Algebra, 2:00-3:00 RH222 | Arturo Magidin, University of Montana | Capability and the nilpotent product of groups |
| Abstract:
In 1940, Phillip Hall pointed the way towards the classification
of the groups of prime power order. In that context, he said:
The question of what conditions a group $K$ must fulfill in
order that it may be the central quotient of another group $G$, $K\cong
G/Z(G)$, is an interesting one. But while it is easy to write down a
number of necessary conditions, it is not so easy to be sure that they are
sufficient.''
This difficulty has resulted in few characterisations of families of
capable groups (groups which are the central quotient of a group). Baer
had characterised the capable abelian p-groups in 1938, but very little
progress beyond his work was forthcoming for about 40 years.
In the past couple of decades, the use of cohomological constructions (the
epicenter and the nonabelian tensor product) have given a new impulse to
the study of capability. They resulted in a characterisation of the
capable extra-special p-groups, and a host of new necessary and new
sufficient conditions for capability. Unfortunately, they seem to be hard
to use in practice.
I will talk instead about a different approach which uses an old notion,
the nilpotent product of groups. It plays the same role for
nilpotent groups of a given class that the direct sum plays for abelian
groups and the free product plays for groups (it is an instance of a
General Algebra construction). Using the nilpotent product, we
can obtain a generalisation of Baer's result, and a characterisation of
the capable 2-generated p-groups of class two, p an odd prime (among
other results). The advantage of this approach, as I hope will be clear
from the talk, is that the notions and ideas are very low-tech and have a
much lower ``start-up cost'' than the cohomological techniques of recent
years.
|
| Fri. Oct. 31 | Topology, 4:00-5:00 RH142 | Andy Miller, University of Oklahoma | Hopf tori in elliptic 3-manifolds |
| Tues. Nov. 4 | Comp. Sci., 4:10-5:00 RH316 | Kevin Scannell | From Eugene Onegin to a Maori grammar checker: a survey of statistical natural language processing, II |
| Thurs. Nov. 6 | Algebra, 2:00-3:00 RH222 | Greg Marks | Annelidan rings and group algebras |
| Fri. Nov. 7 | Analysis, 1:00-2:00 RH109 | Darrin Speegle | A counterexample to Fuglede's conjecture, a result of Tao |
| Abstract:
In 1974, Bent Fuglede conjectured that
for any measurable set $E\subset R^d$, there is an
orthonormal basis of exponentials for $L^2(E)$ if
and only if there is a collection of points
$T\subset R^d$ such that {E+k: k\in T} is an
almost everywhere partition of R^d. We will
present some progress on this conjecture in the
last 10 or so years, then give the ideas for the
counterexample due to Terence Tao, discovered in
June, 2003.
The idea of the proof boils down to finding
Hadamard matrices (orthogonal matrices whose
entries are a pth root of unity) of order not
equal to a power of p. When p = 2, the first
example occurs in dimension 12, and when p = 3,
the first example occurs in dimension 6. This
gives counterexamples to the "discrete version of
Fuglede conjecture" in Z_2^12 and Z_3^6. Then,
standard transference
techniques give the counterexamples in R^12 and
R^6.
I will focus on the discrete version of Fuglede's
conjecture, where the ideas are very accessible
and could be of interest to algebraists in the
department. In particular, there are natural open
questions related to finding the smallest Hadamard
matrix of the type that gives counterexamples to
Fuglede's conjecture.
|
| Thurs. Nov. 13 | Algebra, 2:00-3:00 RH222 | Greg Marks | Annelidan rings and the Köthe conjecture |
| Abstract:
In the early 1990's Mallat and Zhong developed a
wavelet-based technique for the characterization of one- and
two-dimensional signals in
terms of their multi-scale edges. Understanding such edges
is important in applications like pattern recognition or
computer vision. This talk
is intended to give an overview of the Mallat-Zhong approach
through basic theory and numerical examples. No familiarity
with wavelets is assumed.
|
| Thurs. Nov. 20 | Algebra, 2:00-3:00 RH222 | Greg Marks | Exchange rings |
| Tues. Dec. 2 | Algebra, 2:00-3:00 RH29 | John Kalliongis | Group-theoretic problems in 3-manifold topology |
| Thurs. Dec. 4 | Algebra, 2:00-3:00 RH222 | Greg Marks | Exchange rings, II |
| Thurs. Dec. 4 | Topology, 3:45-4:45 RH134 | Steve Harris | Three topologies for boundaries of spacetimes, I |
| Fri. Dec. 5 | Analysis, 1:00-2:00 RH109 | Brad Currey | Wavelet transforms for semi-direct product groups (after Ishi) |
| Thurs. Dec. 11 | Topology, 3:45-4:45 RH134 | Steve Harris | Three topologies for boundaries of spacetimes, II |
| Thurs. Dec. 18 | Algebra, 2:00-3:00 RH222 | Greg Marks | Exchange rings, III |
Math & CS Home