University of Georgia
Department of Mathematics

Seminar Schedule
October 2 - 6, 2006

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

MONDAY, October 2, 2006

Topology
2:30pm, Room 304
Speaker: TBA
Title of talk: TBA

Algebra
2:30pm, Room 410
Speaker: Emilie Weisner, UGA
Title of talk: Cohomology of Category $\mathcal O$ for the Virasoro algebra
Abstract: I will talk about some results on the blocks of the category $\mathcal O$ for the Virasoro algebra. BGG resolutions exist for the simple modules in $\mathcal O$, which allow us to compute $Ext^n_ {\mathcal O} (M(\mu), L(\lambda))$, for a Verma module $M(\mu)$ and a simple module $L(\lambda)$. Using the theory of highest weight categories developed by Cline, Parshall, and Scott, we can also compute $Ext^n_{\mathcal O} (L(\lambda), L(\mu))$ and show certain algebras are Koszul.

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

TUESDAY, October 3, 2006

VIGRE Graduate Student Seminar
2:00pm, Room 302
Speaker: Bobbe Cooper, University of Georgia
Title of talk: Tips for Surviving Graduate School
Abstract: In this talk I will discuss strategies for managing your time and being productive in graduate school -- while keeping your sanity. We'll talk about balancing school and personal life, organizing office space, dealing with the multiple strains on your time, and getting motivation for long-term projects and day-to-day tasks. I'll also describe some nitty-gritty practical ways to start and continue mathematical research. This talk should be accessible to first-year graduate students.

Special Number Theory Talk
3:30pm, Room 304
Speaker: R. Parimala, Emory
Title of talk: Rational points on homogeneous spaces.
Abstract: Let G be a connected linear algebraic group defined over a field and X a principal homogeneous space under G. There are open questions concerning whether the existence of a zero cycle of degree one implies the existence of a rational point on X. We discuss the case of number fields where these questions admit a positive response and explain known results in a general context.

Analysis
3:30pm, Room 222
Speaker: Neil Lyall, University of Georgia
Title of talk: On a Theorem of Sarkozy I: Introduction (continued)
Abstract: A theorem of Sarkozy and Furstenberg states that the difference set A-A of any given subset A of positive (upper) density in the integers necessarily contains a square.

In last week's seminar we discussed this theorem, indicated how it relates to Szemeredi's Theorem, and announced our strengthening of Sarkozy's theorem:

There exists an integer M=M(A) such that any collection of M consecutive integers necessarily contains an integer whose square is an element of A-A.

We hope to do the following:

1. Conclude arguments that establish the analogous result without the "square" requirement; namely the existence of an integer M=M(A) such that A-A intersects every interval of integers of length M.

2. Prove Roth's theorem (Szemeredi's theorem for arithmetic progressions of length three).


WEDNESDAY, October 4, 2006


Algebraic Geometry
2:30pm, Room 410
Speaker: Elham Izadi, University of Georgia
Title of talk: New correspondences on curves and Prym-Torelli, I
Abstract: A correspondence on a curve C is another curve embedded in the cartesian product of C with itself. In this first talk I will explain a geometric way of constructing new correspondences on some special curves. In a second talk I will show how these correspondences satisfy polynomial equations with integer coefficients and give rise to new conterexamples to the Prym-Torelli problem.

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

Arithmetic Geometry/Number Theory
3:30pm, Room 304
Speaker: Andrew Granville, Montreal
Title of talk: Rational and integral points on quadratic twists of hyperelliptic curves.
Abstract: Elkies' proof that abc implies Faltings theorem (that there are finitely many rational points on an algebraic curve X of genus >1) does effectively bound the height of rational points though in terms of the height of the Belyi map (from X to P^1) which tends to be very large. However by running through certain (carefully selected) families of curves we can have more control over the Belyi maps, and thus obtain more useful height bounds.

THURSDAY, October 5, 2006

VIGRE-Algebraic Geometry
2:00pm, Room 410

Wavelets and Splines
2:30pm, Room 524
Speaker: Dr. Jie Zhou, University of Georgia
Title of talk: Image Compression by Wavelets with dilation=3
Abstract: We present a new method to construct orthonormal wavelets with dilation=3
and apply our wavelets for image compression. We show that we can compress
images at compression ratio 128:1 with excellent reconstruction.


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

Colloquium
3:30pm, Room 304
Speaker: Andrew Granville, Montreal
Title of talk: Various pretentious characters
Abstract: We explain how certain key results in analytic number theory can be rephrased in terms of pretentiousness, and discuss some joint results with K. Soundararajan motivated by this new concept.

VIGRE - Quantum Mechanics
4:45, Room 410
David Finkelstein will speak on Homotopies to algebraic quantum gravity.

FRIDAY, October 6, 2006

Probability Theory
2:30pm, Room 323
Speaker: Lirong Yu, University of Georgia
Title of talk: Optimal control of switching diffusions (cont.)

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

VIGRE-Algebra
2:30pm, Room 304