University of Georgia
Department of Mathematics

Seminar Schedule
April 14 - April 18, 2008

All Seminars are held in Boyd Graduate Studies Bldg. unless otherwise noted.

MONDAY, April 14, 2008


VIGRE – Algebraic Geometry
2:15pm, Room 222

Topology
2:30 pm   Monday, April 14, 2008
Geometry Topology Seminar- Joint meeting at GaTech: Counter-examples to the stabilization conjecture for Heegaard splittings by David Bachman (Pitzer) in Skiles 269

Joint UGA-GaTech meeting here at Tech: 75 years ago Reidemeister and Singer proved that any pair of Heegaard splittings are equivalent after some number of stabilizations. We present the first example of a pair of splittings that require more than one stabilization to be equivalent.

3:45 pm   Monday, April 14, 2008
Geometry Topology Seminar- Joint meeting at GaTech: Stabilizing and flipping Heeegaard splittings
by Jesse Johnson (Yale) in Skiles 269

Every Heegaard splitting of a closed 3-manifold has a stabilization such that there is an isotopy of the 3-manifold that interchanges the handlebodies. I will describe a combinatorial proof that, the genus of the smallest such stabilization is bounded below by the smaller of twice the genus or half the Hempel distance of the original splitting. Similar methods imply that for certain 3-manifolds with boundary, there are pairs of Heegaard surfaces for which the minimal genus of a common stabilization is very high. The proof is inspired by the recent paper by Hass, Thompson and Thurston, which proves similar results using hyperbolic geometry, but without a precise bound in terms of the Hempel distance of the Heegaard splitting.



Algebra
2:30pm, Room 410
Speaker: Wenjing Li (UGA)
Title of talk: Non-Associative Binary Algebraic Structures
Abstract: Right quasigroups and quandles are non-associative binary algebraic structures. The interest here is representation of quandles. We prove that for every homogeneous quandle $Q$, there exists a triple $(G,H,s)$ that is isomorphic to $Q$, for $H$ a subgroup of a group $G$ where an automorphism $s$ of $G$ fixing $H$ pointwise is needed to describe the quandle operations on $H\backslash G$. We define quandle cohomology groups and discuss how the quandle 2-cocycle condition is related to knot invariants.

Faculty and Graduate Social
3:00pm, Room 409
Coffee, Tea, Cookies


TUESDAY, April 15, 2008

VIGRE - Graduate Student Seminar
2:00pm, Room 304
Speaker: TBA
Title of talk: TBA
Abstract: TBA

Mathematical Physics
3:30pm, Room 303
Speaker: TBA
Title of talk: TBA
Abstract: TBA

Geometry
3:30pm, Room 304
Speaker: TBA
Title of talk:
TBA
Abstract:
TBA



WEDNESDAY, April 16 2008

Algebraic Geometry
2:30pm, Room 410
Speaker: TBA
Title of talk: TBA
Abstract: TBA

Faculty and Graduate Social
3:00pm, Room 309
Coffee, Tea, Cookies

A Mathematica Presentation
3:30-4:30pm, Room 303
Speaker: Kathy Kirk (Wolfram)
Title: "Mathematica 6 in Education and Research"
This talk illustrates capabilities in Mathematica 6 that are directly applicable for use in teaching and research on campus. Topics of this technical talk include:

* 2D and 3D visualization
* Dynamic interactivity
* On-demand scientific data
* Example-driven course materials
* Symbolic interface construction
* Practical and theoretical applications

Current users will benefit from seeing the many improvements and new features of Mathematica 6 (http://www.wolfram.com/mathematica/newin6), but prior knowledge of Mathematica is not required.


Number Theory
3:30pm, Room 304
Speaker: TBA
Title of talk: TBA
Abstract: TBA


THURSDAY, April 17, 2008

VIGRE – Tropical Geometry
2:00pm, Room 304

VIGRE – Circle Packing
2:00pm, Room 410

Faculty and Graduate Social
3:00pm, Room 409
Coffee, Cookies, Tea

Colloquium
3:30pm, Room 304
Speaker: Professor Yang Wang, Michigan State University
Title of talk: The Golden Ratio Encoder for Analog-to-Digital Conversion
Abstract:  The advent of computer and digital information technologies and their development have greatly changed the world we live in. Today digital technologies are everywhere in our lives. A key step that makes all those technologies possible is to convert analog data into digital ones, a process known analog-to-digital conversion, or A/D conversion. With demand for higher precision and more cutting-edge technologies, the mathematics of A/D conversion algorithms plays an important role in this quest. In this talk we review algorithms for A/D conversions and the associated problems concerning stability and robustness. We discuss a new algorithm for A/D conversion using the golden ratio expansion for real numbers and the Fibonacci sequence. We show that this new A/D encoder have many advantages over the traditional A/D encoders.

VIGRE – Number Theory
3:30pm, Room 303


FRIDAY, April 18, 2008

VIGRE-Algebra
2:30pm, Room 322

Applied Math
2:30pm, Room 302
Speaker: TBA
Title of talk: TBA
Abstract: TBA

Geometry
Please see Tuesday, April 15, 2008