Un of Tenn | Math Department

Seminars and Colloquiums
for the week of March 11, 2013

Speakers:

Jonathan Forde, Hobert and William Smith Colleges, Monday
Prof. Luis Finotti, Monday
Ms. Chelsea Lewis, Wednesday
Prof. Natalie Frank, Chair of Mathematics, Vassar College, Wednesday
Dr. Jerzy Dydak, Thursday
Prof. Natalie Frank, Chair of Mathematics, Vassar College, Thursday
Prof. Vasilis Papanicolaou, Washington Univ., St. Louis and National Technical University of Athens, Greece, Friday

*** Tea Time this week will be Monday - Wednesday at 3:00 pm.
Hosted this week by Samantha Tracht. Everyone is welcome! ***

MONDAY, MARCH 11

SIAM STUDENT CHAPTER
TIME: 12:20 - 1:10 p.m.
ROOM: Ayres 122
SPEAKER: Jonathan Forde, Hobert and William Smith Colleges
TITLE: Modeling the Immune Reaction to Hepatitis Delta infection
ABSTRACT: Hepatitis Delta Virus (HDV) is a dependent satellite virus of the more common Hepatitis B Virus. HDV encodes only one protein of its own, relying on HBV to supply the additional proteins needed for its replication cycle. Although HDV is noncytotoxic and present few targets for immune reaction, the symptoms of patients with HBV-HDV co-infection are much worse than those infected with HBV alone. The cause of this negative outcome is not clear. This talk presents o.d.e. models for the interaction of HBV, HDV and the antigen-speci?c immune responses to explore recovery from T cell exhaustion as a possible explanation of negative outcomes in chronic HBV/HDV co-infection. Additionally, the role of the immune reaction in several other HDV-related phenomena will be discussed, including drug treatment failure and fluctuations in viral load.

Pizza will be available at 3:10 p.m.

ALGEBRA SEMINAR
TIME: 3:35 p.m.
ROOM: Ayres B004
SPEAKER: Prof. Luis Finotti
TITLE: On the ABC Conjecture, part IV
ABSTRACT: S. Mochizuki has recently claimed to have prove the ABC Conjecture. This is a very strong conjecture, with numerous consequences in number theory. If correct, it would be the most important result in mathematics since the proof of the Poincaré Conjecture. In this series of talks we will motivate, state, give equivalent statements, prove/discuss consequences and study related problems to the ABC Conjecture.

WEDNESDAY, MARCH 13

MATH BIOLOGY SEMINAR
TIME: 12:20 - 1:10 p.m.
ROOM: Ayres 114
SPEAKER: Chelsea Lewis
TITLE: Nonlinear Dynamics in Physiology and Medicine (chapter 3 of this book)

ANALYSIS SEMINAR
TIME: 3:35 - 4:25 p.m.
ROOM: Ayres 114
SPEAKER: Prof. Natalie Frank, Chair of Mathematics, Vassar College
TITLE: "Aperiodic Tilings and Fusion"

THURSDAY, MARCH 14

TOPOLOGY SEMINAR
TIME: 9:40 - 10:55 a.m.
ROOM: Ayres Hall B004
SPEAKER: Prof. Jerzy Dydak
TITLE: Coarse amenability and expanders
ABSTRACT: Coarse amenability is a generalization of amenability from groups to metric spaces. Historically, there are three basic classes of coarsely non-amenable spaces: a. expander sequences (G.Yu), b. infinite unions of powers of a given finite group G that is not trivial (P.Nowak), c. graph sequences with girth approaching infinity (R.Willett).

The most explicit construction of an expander sequence is as finite quotients of a finitely generated group G with Kazhdan’s property (T) (example: SL_n(Z) when n > 2).

I will define expander light sequences, prove they are coarsely non-amenable, and show each of the above classes is a subclass of expander light sequences. Not only expander light sequences form a unifying concept for a)-c), the proof of their coarse non-amenability is quite elementary.

JUNIOR COLLOQUIUM
TIME: 3:35 - 4:25 p.m.
ROOM: Ayres 405
SPEAKER: Prof. Natalie Frank, Chair of Mathematics, Vassar College
TITLE: Tiling: a mathematical model of crystals and quasicrystals
ABSTRACT: In 2011, Daniel Shechtman was awarded the Nobel Prize for Chemistry for his discovery of quasicrystals. This discovery, in 1982, required a rethinking of how to describe the atomic structure of highly organized solids. Fortunately, the mathematics community had been working for over a decade on the sort of tilings that have such a structure. We'll tell the story of how tilings came to be used as models for quasicrystals, and discuss some of the mathematics.

Pizza will be available at 3:10 p.m.

FRIDAY, MARCH 15

COLLOQUIUM
T IME: 3:35 - 4:25 p.m.
ROOM: Ayres 405
SPEAKER: Prof. Vasilis Papanicolaou, Washington Univ., St. Louis and National Technical University of Athens, Greece
TITLE: Asymptotics and Limit Distributions for the General Collectors Problem
ABSTRACT: Let $T_N$ be the number of coupons that a collector has to buy in order to find all $N$ existing different coupons. The probabilities (occurring frequencies) of the coupons can be quite arbitrary. Using the asymptotics of the expectation and variance of $T_N$ as $N \to \infty$ and the general limit theorems of P. Neal, we derive the limit distribution of $T_N$ (appropriately normalized), which, for a large class of probabilities, turns out to be the standard Gumbel distribution. Our results extend a well-known result of P. Erdos and A. Renyi.

Joint work with Aris tides V. Doumas.

Refreshments will be available at 3:10 p.m.

If you are interested in giving or arranging a talk for one of our seminars or colloquiums,
please review our calendar.

If you have questions, or a date you would like to confirm, please contact colloquium AT math DOT utk DOT edu

Past notices: