Seminars and Colloquiums
for the week of November 17, 2008
Speakers:
Mr. Justin Grieves, Monday
Mr. Justin Grieves & Mr. Zhiqiang Li, Monday
Mr. Michael Lawton , Tuesday
Assistant Professor Mrinal Raghupathi, Vanderbilt University, Wednesday
Mr. Derek Rose, Elec Engr & Comp Science, UTK, Thursday
Associate Professor Grozdena Todorova, Friday
Monday, November 17
PROBABILITY SEMINAR
TIME: 10:10 – 11:00 a.m.
ROOM: Ayres 209A
SPEAKER: Mr. Justin Grieves
TITLE: “Moderate Deviation of Intersection of Ranges of Random Walks in the Stable Case [A Preliminary Report]” (Continued)
DIFFERENTIAL EQUATIONS and
COMPUTATIONAL MATHEMICS SEMINAR
TIME: 3:35 – 4:25 p.m.
ROOM: Ayres 309A
SPEAKER: Mr. Justin Grieves
TITLE: “A Numeric Approach to Solving Stochastic Differential Equations”
SPEAKER: Mr. Zhiqiang Li
TITLE: “Numerical approximation for functionals of reflecting diffusion Processes”
Tuesday, November 18
MATH ECOLOGY SEMINAR
TIME: 10:00 – 10:50 a.m.
ROOM: Ayres 205
SPEAKER: Mr. Michael Lawton
TITLE: “ Spatial Disease Models - Metapopulations and Lattice-based models”
Wednesday, November 19
ANALYSIS SEMINAR
TIME: 3:35 – 4:30 p.m.
ROOM: Ayres 309B
SPEAKER: Assistant Professor Mrinal Raghupathi, Vanderbilt University
TITLE: "Representations of Logmodular Algebras"
ABSTRACT: It is still an open problem as to whether every representation of $H^\infty$, the algebra
of bounded analytic functions on the unit disk, dilates. The problem is relevant to the study of
nonselfadjoint operator algebras, and is rooted in developments in operator theory in the 1950s and 1960s.
In this talk I will try to provide some motivation as to why we would like to study this problem and
then present some joint work with Vern Paulsen on representations of noncommutative logmodular
algebras.
Thursday, November 20
JUNIOR COLLOQUIUM
TIME: 3:40 – 4:30 p.m.
ROOM: Ayres 214
SPEAKER: Mr. Derek Rose, Elec Engr & Comp Science, UTK
TITLE: "A Quick Introduction to Reinforcement Learning"
ABSTRACT: Reinforcement learning (RL) is an exciting and relatively new machine learning discipline,
which corresponds to a broad class of methods that allow a system to learn how to behave in
stochastic environments based on reward signals. A key concept in RL is that the intelligent agent
learns by itself, based on acquired experience, rather than by being explicitly instructed or
supervised. The talk will cover the basic concept pertaining to the theory and practice of RL.
Pizza will be served.
Friday, November 21
MATHEMATICS COLLOQUIUM
(promotion candidate)
TIME: 3:35 – 4:25 p.m.
ROOM: Ayres 214
SPEAKER: Associate Professor Grozdena Todorova
TITLE: “Critical Exponent for Nonlinear Wave Equations with Space-Dependent Potential”
ABSTRACT: We study the problems of global existence or finite-time blow up for small data solutions
of a class of nonlinear wave equations with spatial inhomogeneity of the potential in the dissipative
term. We show the existence of the threshold effect which separates out the two kinds of behavior.
Sharp critical exponent results will be presented in the case of slow and fast decaying potential.
They reflect the fact that increasing the decay rate of the potential gradually weakens
asymptotically parabolic effects of dissipative wave equations and we observe a transition to the
pure hyperbolic regime when the decay of the potential becomes sufficiently fast.
To get sharp critical exponent results, precise decay estimates for the corresponding linear problems
are needed. This is a delicate task in the case of a space dependent potential and has been an open
problem. Recently we have developed a technique which allows us to derive the optimal decay of
solutions for the linear problems with space dependent potential. We apply a modification of this
approach to the nonlinear problem to be able to solve the global existence part of the critical
exponent problem. We shall also discuss other interesting phenomena due to the presence of the
dissipative term.
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:
Past notices:
Seminars from 2007-2008 academic year
Seminars from 2006-2007 academic year