Un of Tenn | Math Department

Seminars and Colloquiums
for the week of November 9, 2009

Speaker:

Mr. Zhen Guan, Monday
Mr. Matt Turner, Monday
Professor Suzanne Lenhart, Tuesday
Ms. Erin Bodine, Tuesday
Mr. Jon Gray, Wednesday
Professor Stefan Richter, Wednesday
Professor Conrad Plaut, Thursday
Professor Mu-Tao Wang, Columbia University, Friday

Monday, November 9

COMPUTATIONAL & APPLIED MATH SEMINAR
TIME: 3:35 – 4:25 p.m.
ROOM: HBB 112
SPEAKER: Mr. Zhen Guan
TITLE: “Adaptive ODE solvers for stiff problems”
ABSTRACT: In this talk I will discuss two adaptive ODE solver and compare their results on stiff problem. First I will discuss the motivation, the approximation of the complex Ginzburg–Landau (CGL) equation. Then I will discuss the adaptive Runge-Kutta method and its potential disadvantages in this stiff problem. After that I will introduce the Gragg-Bulirsch-Stoer method. This method may provide a better result. At the end I will compare these two methods and discuss the future direction for an ideal solver for CGL equation.

PROBABILITY SEMINAR
TIME: 3:35 – 4:25 p.m.
ROOM: HBB 132
SPEAKER: Mr. Matt Turner
TITLE: “Infinitely divisible random measures on time and space:
Stochastic Integration. Part 2.”
ABSTRACT: This will be a two part talk introducing and characterizing stochastic
integration with respect to infinitely divisible random measures (IDRM) on time and space. In part 1, I will introduce infinitely divisible distributions, processes and random measures. Then, I will introduce stable random measures and provide an analog to the Ito isometry for stochastic integrals with respect to stable random measures. In part 2, I will characterize stochastic integration with respect to an arbitrary IDRM and apply these results to tempered stable random measures.

Tuesday, November 10

MATH ECOLOGY SEMINAR
TIME: 9:00-10:00 a.m.
ROOM: Temple 303
SPEAKER: Professor Suzanne Lenhart
TITLE: “Strategies for controlling exotic pests”

GTA SEMINAR
TIME: 3:35 p.m.
ROOM: Temple 303
SPEAKER: Ms. Erin Bodine
The 4th LaTeX Seminar will cover the use of Beamer to make presentations and posters.

Wednesday, November 11

COARSE GEOMETRY SEMINAR
TIME:  11:15 – 12:05 p.m.
ROOM:  HBB 112
SPEAKER:  Professor Jerzy Dydak
TITLE:   "Coarse embeddings of graphs into the Hilbert space"
ABSTRACT: We discuss obstructions to embeddings of graphs in to H. Expanders are the primary example.

ALGEBRA SEMINAR
TIME: 2:30 – 3:20 p.m.
ROOM: 1st Floor, Temple Court (Math Tutorial Center)
SPEAKER: Mr. Jon Gray
TITLE: “(Co/Bi/Hopf-) Algebras” III

ANALYSIS SEMINAR
TIME: 3:35 – 4:30 p.m.
ROOM: AC 113
SPEAKER: Professor Stefan Richter
TITLE: “Two-isometric operators and operator tuples on Hilbert spaces, III”

GEOMETRIC ANALYSIS SEMINAR (Optimal Transportation)
TIME: 4:30 – 5:30 p.m.
ROOM: HBB 102
SPEAKER: TBA
TITLE: TBA

Thursday, November 12

JUNIOR COLLOQUIUM
TIME: 3:35 – 4:35 p.m.
ROOM: HBB 102
SPEAKER: Professor Conrad Plaut, UTK
TITLE: “A pair of geometric inequalities”
ABSTRACT: We will consider two questions: (1) What is the maximum area that can be bounded by a closed curve of length 1 in the plane, and which curves, if any, realize this maximum? (2) What is the maximum area of a convex surface in 3-space having diameter 1, and which surfaces, if any, realize that maximum? (I will explain what a convex surface is—the concept is very simple and intuitive). The answer to the first question was known to the Greeks, although it wasn’t until the latter half of the 19th century that the statement was really proved, by Weierstrass. The answer to the second question is still unknown. In 1955 A.D. Alexandrov conjectured that the area is bounded above by pi/2, and he exhibited a very simple surface that realizes this area. But this surface, unlike the circle, is not smooth, and not even really a convex surface. At the present time it is not even known whether there is a maximum area, or, if there is one, if it is realized by a smooth surface. After almost 55 years this very interesting question is still waiting to be solved.
FOOD: Free Pizza in AC113 @3:15 p.m.

Friday, November 13

MATHEMATICS COLLOQUIUM
TIME: 3:35-4:35 p.m.
ROOM: HBB 102
SPEAKER: Professor Mu-Tao Wang, Columbia University
TITLE: “Isometric embeddings of surfaces and quasilocal gravitational energy”
ABSTRACT: In general relativity, the gravitational field is represented by the Lorentz metric of spacetime. Einstein's field equation relates the gravitation and matter fields. The total energy contained in a bounded region in the universe has contributions from both sources. Matter fields have energy density and the energy can be evaluated as a flux integral over the boundary. However, the equivalence principle prevents the existence of energy density for gravitation. On a large scale, the gravitation dominates but the measurement of the gravitational energy is extremely subtle as it depends of the geometric configuration which is distorted by the underlying presumably nonflat Lorentz metric. In this talk, I shall explain a new way to measure the total energy contained in a bounded region using tools from differential geometry and PDE's, in particular the isometric embedding of the boundary surface. This is a joint work with S. T. Yau at Harvard.

Refreshments at 3:15 in the basement.

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. Steve Wise.

Week of: