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Upcoming Seminars
MONDAY, March 3, 2008
GRADUATE STUDENT RESEARCH SEMINAR PSA 103 12:00 p.m.
Chris Severs, Department of Mathematics and Statistics
"A-Theory and the Associahedron"
ABSTRACT: The associahedron is a polytope that has many
combinatorial interpretations and generalizations. We have used
the A-Theory of Barcelo, et al., to explore the discrete
fundamental group of the associahedron. With the aid of
computer algebra software we have conjectured that the discrete
fundamental group, A_{1}^{n-1}, of the n-dimensional
Associahedron of Coxeter type-A has rank \binom{n+2}{4}. In
this talk we will present all needed background in A-Theory and
a description of the associahedron, as well as the methods used
in our proof of the conjecture.
This is joint work with Hélène Barcelo and Jacob White.
Bagels and juice will be served in PSA 103 at 11:50 a.m.
COLLOQUIUM (SCHOOL DIRECTOR CANDIDATE) PSF 101 1:15 p.m.
Jerry Bona, University of Illinois at Chicago
"Water Wave Theory and Some Applications"
ABSTRACT: The lecture will commence with a brief historical
perspective of the development of modern water wave theory. The
conversation will then turn to checking how well the theory
works in controlled, laboratory settings. Finally, applications
to sand bar formation and beach protection, tsunami propagation
and rogue wave formation will be outlined as time permits.
At the end of the talk, Dr. Bona will address his vision for
the new school.
Refreshments will be served in 2nd floor breezeway
at 1:00 p.m.
CRESMET COLLOQUIUM University Center 201 3:30 p.m.
1130 E. University Dr. (behind Chompies)
(Hosted by Center for Research on Education in Science,
Mathematics, Engineering and Technology)
Shlomo Vinner, former head of Science Education Departments at
Hebrew University, Jerusalem and Bern Gurion
University, Beer Sheva
"Mathematics Education - Procedures, Rituals and Man's Search
for Meaning"
ABSTRACT: An attempt is made to analyze mathematical behavior
from more general psychological perspectives. The mathematical
language is a special case of the human language which is a
form of expression. Many people use common language in a
meaningless way. The same is true about the mathematical
language. Rituals are other forms of expression. Many people
who study mathematics in a meaningless way very often identify
rituals in some mathematical contexts (procedures,
argumentation and proof). Thus, quite often, they behave in a
meaningless way as required by certain rituals. In some cases
this explains what I called in an earlier work pseudo
conceptual and pseudo analytical behaviour. On the other hand,
the community of the mathematics education struggle for
meaningful learning. This can be regarded as a special case of
Man's search for meaning. The general claims will be illustrated
by some examples from various mathematical contexts.
BRIEF BIO: He was a high school mathematics teacher for 10 years
while studying mathematics, physics and philosophy at the
Hebrew University. After finishing his Ph.D. in mathematics he
switched to mathematics education. His research interest was
mainly in mathematical concept formation, thought processes. In
recent years his main concern is in the question how can the
teaching of mathematics be used in order to promote educational
values, the ultimate goal of education.
COMPUTATIONAL AND APPLIED MATHEMATICS PROSEMINAR
GWC 487 4:30 p.m.
Russ Park, Department of Mathematics and Statistics
"Optimal Compression and Numerical Stability of Gegenbauer
Reconstructions" (oral exam)
ABSTRACT: Image reconstruction methods are characterized by the
source data space on which they operate, the range space and
the degree to which objectives such as artifact suppression,
compression and numerical stability are optimized. The
Gegenbauer reconstruction method operates on Fourier source
data, projecting it onto a finite set of Gegenbauer polynomials.
Gegenbauer data is then expanded on sub-domains of physical
space segmented by presumed jump discontinuities in the source
data. The absence of jump discontinuities within each sub-domain
assures spectral convergence as long as reconstruction
parameters lambda and m linearly track the resolution N as it
approaches infinity. The implicit benefit of Gegenbauer
reconstruction is source data compression, unfortunately the
process is also limited by numerical instability as either
lambda or m, or both, increase.
Early studies on this issue assumed lambda and m to be
linearly tied to N and then characterized the bounds of
instability as well as recommended safe reconstruction
parameter combinations. Subsequent work demonstrated how to
automatically predict the source data smoothness parameters, of
which apriori knowledge is required for accurate
reconstruction. This study performs asymptotic analyses on the
predicted error bounds as N goes to infinity while fixing
either m or lambda, leading to the discovery of reconstruction
parameters optimized for an objective of either compression or
numerical stability. Finally, the effectiveness of this new
approach is illustrated by extensive numerical experiments.
TUESDAY, March 4, 2008
MATHEMATICS AND COGNITION SEMINAR PSA 206 12:15 p.m.
Gregor Wolbring, Center for Nanotechnology in Society, ASU,
University of Calgary
"The Mathematics of Beyond-Species-Typical Functioning"
Cookies and coffee will be served at 12:00 p.m.
ANALYSIS / PDE SEMINAR ECG 315 2:00 p.m.
Tsuyoshi Yoseda, The University of Tokyo, Japan
"On Time Analyticity of the Navier-Stokes Equations in a
Rotating Frame with Spatially Almost Periodic Data"
APPLIED ANALYSIS AND PDE READING SEMINAR PSA 546 3:00 p.m.
For more information, contact Svetlana Roudenko.
WEDNESDAY, March 5, 2008
DISTINGUISHED LECTURE SERIES PSA 304 1:30 p.m.
Yakov Sinai, Princeton University
"Diagrams and Expansions of Solutions of the 3-dimensional
Navier-Stokes System"
ABSTRACT: I shall consider the Fourier transform of the 3-dim
Navier-Stokes system. There are some natural functional spaces
in which local existence theorems are valid. In the limiting
case of the so-called critical case the global existence
theorem is valid for small initial condition while the
situation with large initial condition is completely open. In
general, solutions can be represented as series of diagrams.
Some estimates of these diagrams will be presented. The whole
theory requires new notions of convolutions.
Refreshments will be served in PSA 546 at 2:30 p.m.
COMPUTATIONAL AND APPLIED MATHEMATICS PROSEMINAR
GWC 487 1:40 p.m.
Yin Zhang, Rice University
"Large-Scale L1-Related Minimization in Compressive Sensing
and Beyond"
ABSTRACT: Compressive sensing (CS) has recently been actively
studied because of its promises in many potential applications.
From CS and other related areas arise a number of large-scale
optimization problems with non-smooth regularization terms such
as L1-norm.
In this talk, we will consider several such formulations,
discuss algorithmic challenges involved, and introduce some
existing approaches. In particular, we will focus on
theoretical and numerical results for a fixed-point
continuation (FPC) algorithm. We will also briefly discuss
issues of exploiting problem structures.
NUMBER THEORY SEMINAR PSA 308 1:40 p.m.
Alejandra Alvarado, Department of Mathematics and Statistics
"Arithmetic Progressions on Curves"
ABSTRACT: An arithmetic progression is a sequence of numbers
such that the difference between any two consecutive numbers is
constant. When we talk about an arithmetic progression on a
curve F(x,y)=0, we mean an arithmetic progression in the x
coordinates. In this talk we will discuss APs on curves of
genus greater than zero. In particular, we will look at APs on
certain types of elliptic curves.
ECOSYSTEMS ENGINEERING SEMINAR ISTB2 229 4:40 p.m.
William Gustafson, Pacific Northwest National Laboratory
"Present and Future Possibilities for Numerical Atmospheric
Modeling"
ABSTRACT: The complexity and scale of the atmosphere makes
direct experimentation impossible for many questions facing
atmospheric scientists today. Specifically for physical
experiments addressing climate change, experimentation also
brings ethical implications that have yet to be definitely
resolved. So, atmospheric scientists use sophisticated
numerical models to represent reality with the goal of
predicting the nonlinear response of the system to various
scenarios representing anthropogenic influences. What physical
processes are included in today's atmospheric models? What are
the open questions currently being debated? And, how are these
models expected to evolve over the next decade? These questions
will be addressed in the context of the Weather Research and
Forecasting (WRF) model, which is a state-of-the-art regional
atmospheric model capable of simulating urban to global
meteorology and chemistry.
THURSDAY, March 6, 2008
DISTINGUISHED LECTURE SERIES PSA 206 4:00 p.m.
Yakov Sinai, Princeton University
"Singularities of Complex Solutions in the Equations of the
Fluid Dynamics and Renormalization Group Method"
ABSTRACT: In a series of joint papers with Dong Li we developed
a method which allows to construct solutions of Navier-Stokes
systems having singularities in finite time of real solutions
in Fourier space. The method is based on the renormalization
group theory.
Refreshments will be served in PSA 206 at 3:15 p.m.
FRIDAY, March 7, 2008
C*-ALGEBRA SEMINAR PSA 307 2:40 p.m.
Kamran Reihani, Department of Mathematics and Statistics
"Spectral Triples for Trees, II"
(Joint work with Matilde Marcolli)
MATH BIOLOGY SEMINAR ECG 237 3:40 p.m.
Azmy S. Ackleh, University of Louisiana at Lafayette
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