Un of Tenn | Math Department

Seminars and Colloquiums
for 2010-2011

Week of April 11, 2011

Speaker:
Dr. Marty Golubitsky, Director of Mathematical Biosciences Institute, Ohio State University and former SIAM President, Monday
Professor Jan Rosinski, Monday
Mr. Ben Levy, Tuesday
Professor Steve Wise, Wednesday
Mr. Zachary Smith, Wednesday
Professor Judy Walker, University of Nebraska, Thursday
Dr. Karsten Grove, University of Notre Dame, Thursday
Dr. Karsten Grove, University of Notre Dame, Friday
Fifth Annual UT Undergraduate Math Conference, Saturday

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 Dr. Fernando Schwartz.

Monday, April 11

SIAM Student Chapter Talk and Pizza Lunch
TIME: 12:20 - 1:10 p.m.
ROOM: Ayres 405
SPEAKER: Dr. Marty Golubitsky, Director of Mathematical Biosciences Institute, Ohio State University and former SIAM President
TITLE: Animal Gaits and Oscillations in Coupled System

PROBABILITY SEMINAR
TIME: 3:35 - 4:25 p.m.
ROOM: Ayres 114
SPEAKER: Professor Jan Rosinski
TITLE: Identification of semimartingales within infinitely divisible processesî Part III

Tuesday, April 12

MATH BIOLOGY SEMINAR
TIME: 9:45 10:45 a.m.
ROOM: Ayres 405
SPEAKER: Mr. Ben Levy
TITLE: "Stochastic Differential Equations, part 2"

Wednesday, April 13

APPLIED/COMPUTATIONAL MATH SEMINAR
TIME: 3:35 - 4:30 p.m.
ROOM: Ayres 111
SPEAKER: Professor Steve Wise
TITLE: Multigrid Methods and Convergence, Part 2 of 3
ABSTRACT: Multigrid solvers are optimal order iterative solvers for a class of linear (and weakly nonlinear) equations resulting from the discretization of elliptic and elliptic-like PDEs. In the best case, the amount of work to obtain a "solution" is on the order of N, where N represents the total number of unknowns (i.e., the dimension of the solution vector). Compare this with the work required for Gaussian elimination. In this series I will describe the methods in some detail, giving an intuitive explanation of why the methods are so efficient and describing modifications for nonlinear problems and the adaptive setting. The convergence proofs will be for the simplest cases in the finite difference and finite element frameworks. The prerequisites are modest, advanced calculus and advanced linear algebra should suffice.

ANALYSIS SEMINAR
TIME: 3:35 - 4:25 p.m.
ROOM: Ayres 114
SPEAKER: Mr. Zachary J. Smith
TITLE: Weakly-Factored Spaces and Their Duals II
This week we complete the analogy between H^1-BMO and the weakly factored Dirichlet space with the space \Chi, which is related to Dirichlet-Carleson measures.

Thursday, April 14

JUNIOR COLLOQUIUM
TIME: 1:25 - 2:25 p.m.
ROOM: Ayres 405
SPEAKER: Professor Judy Walker, University of Nebraska
TITLE: What color is my hat? And what does that have to do with my ipod?
ABSTRACT: As each of three people enter a room, either an orange hat or a white hat (with the color chosen randomly and independently) is placed on his head. Each person can see the other hats but not his own. They can discuss strategy before they enter the room, but after they've entered no communication is allowed. Once they've looked at the other hats, the players must simultaneously guess their own hat colors or pass. The group shares a prize if at least one person guesses correctly and no one guesses incorrectly. The "obvious" strategy (one person guesses "Orange" no matter what and the other two pass) yields a 50% success rate. Is there a better strategy? What if there are more than three players? We will use the theory of error-correcting codes to find the optimal strategy for this game in many situations.

Pizza will be available at 3:15 p.m.

COLLOQUIUM
TIME: 2:30 - 3:30 p.m.
ROOM: Ayres 405
SPEAKER: Karsten Grove, University of Notre Dame
TITLE: "Positive Curvature and Tits Geometry"
ABSTRACT: Polar actions form a simple yet rich collection of transformation groups extending cohomogeneity one actions, i.e., actions with 1-dimensional orbit space. In positive curvature the study of cohomogeneity one manifolds has lead to the discovery and construction of many new candidates and one new example. In contrast, for higher cohomogeneity it turns out that the problem is intimately related to Tits buildings, and we prove that all such actions of cohomogeneity at least 3 with positive curvature are equivalent to polar actions on rank one symmetric spaces.

All terms will be defined in the talk which describes joint work with F. Fang and G. Thorbergsson.

Please join us for refreshments at 3:15 p.m.

Friday, April 15

COLLOQUIUM
TIME: 3:35 - 4:35 p.m.
ROOM: Ayres 405
SPEAKER: Professor Judy Walker, University of Nebraska
TITLE: Codes on graphs: Shannon's challenge and beyond
ABSTRACT: Whenever information is transmitted across a channel, errors are bound to occur. It is the goal of coding theory to find efficient ways of adding redundancy to the information so that errors can be detected and even corrected. Coding theory began in 1948 with Shannon's groundbreaking result that efficient, reliable transmission of information is possible. This result was existential rather than constructive, however, and the challenge over the past half century has been to actually find the codes that Shannon proved must exist. In the past 10-15 years, it has been shown that certain graph-based codes come close to achieving Shannon capacity. Even with these recent advances, however, it is not clear whether Shannon's challenge has truly been answered. We will discuss the current situation as well as what the next big problems are for the field of coding theory.

Saturday, April 16

Fifth Annual UT Undergraduate Math Conference
The Fifth Annual UT Undergraduate Math Conference will be Saturday, April 16, 2011 in the University Center Shiloh Room. The invited speaker will be Michael Axtel of the University of St. Thomas (Minnesota). For specific details, see our conference website www.math.utk.edu/ugconf/

Past notices: