SEMINARS
Updated: 10-28-2009

   
OCTOBER 2009
   
Graduate Student Seminar
Topic: The Congruence Subgroup Problem for SL(n,Z)
Presenter: Daniel Shenfeld, Princeton University
Date:  Thursday, October 29, 2009, Time: 12:30 p.m., Location: Fine Hall 314
Abstract: The group SL(n, k) (k a field) is simple modulo its center, but for a ring A, SL(n, A) is not: the kernels of the maps SL(n,A)-> SL(n,A/I) (I<A an ideal) give many normal subgroups. The congruence subgroup problem asks whether all finite index normal subgroups of SL(n,A) are obtained in this way. I will discuss the case of SL(n,Z) and more generally, when A is the ring of integers of a number field, with some applications.
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: A brief survey of effective equidistribution results in Gamma\G
Presenter: Elon Lindenstrauss, Princeton University
Date:  Thursday, October 29, 2009, Time: 2:00 p.m., Location: Fine Hall 401
Abstract: Equidistribution results for orbits and more general configurations in Gamma\G are a central focus of the theory of flows on homogeneous spaces. A notable example that comes to mind is Ratner's equidistribution theorem. I will survey some old and new quantitive equidistribution results of this flavor by several authors.
   
Discrete Mathematics Seminar
Topic: The minimum number of monochromatic 4-term progressions
Presenter: Julia Wolf, Rutgers University
Date:  Thursday, October 29, 2009, Time: 2:15 p.m., Location: Fine Hall 224
Abstract: It is not difficult to see that whenever you 2-color the elements of Z/pZ, the number of monochromatic 3-term arithmetic progressions depends only on the density of the color classes. The analogous statement for 4-term progressions is false. We shall analyse the reasons for this, and subsequently derive bounds on the minimum number of monochromatic 4-term arithmetic progressions in any 2-coloring of Z/pZ. In the process we touch upon the subject of quadratic Fourier analysis as well as a closely related question in graph theory studied by Thomason et al.: What is the minimum number of monochromatic K_4s in any 2-coloring of K_n?
   
Algebraic Topology Seminar
Topic: On the KO-theory of toric spaces
Presenter: Tony Bahri, Rider University
Date:  Thursday, October 29, 2009, Time: 3:00 p.m., Location: Fine Hall 1201
Abstract: Central in toric geometry and topology are several important spaces which include moment-angle complexes, the Davis-Januszkiewicz space and toric manifolds. In any complex-oriented cohomology theory, the cohomology rings of many of these spaces have elegant descriptions in terms of the underlying combinatorics. For KO-theory however the situation is more complex. Even so, a surprising amount of the structure does survive from the complex-oriented case. A report of joint work in progress with: Luis Astey, Martin Bendersky, Fred Cohen, Don Davis, Matthias Franz, Sam Gitler, Mark Mahowald, Nigel Ray and Reg Wood.
   
Joint IAS/Princeton University Number Theory Seminar
Topic: Generalizations of the Sato-Tate conjecture
Presenter: David Geraghty, Harvard
Date:  Thursday, October 29, 2009, Time: 4:30 p.m., Location: Fine Hall 214
Abstract: I will discuss a recent joint work with Thomas Barnet-Lamb and Toby Gee in which we prove the Sato-Tate conjecture for non-CM regular algebraic cuspidal automorphic representations of GL_2 over a totally real field.
   
Topology Seminar
Topic: Link surgery, monopole Floer homology, and odd Khovanov homology
Presenter: Jonathan Bloom, Columbia University
Date:  Thursday, October 29, 2009, Time: 4:30 p.m., Location: Fine Hall 314
Abstract: I'll describe new bigraded invariants of a framed link in a 3-manifold, which arise as the pages of a spectral sequence generalizing the surgery exact triangle in monopole Floer homology. The construction relates the topology of link surgeries to the combinatorics of polytopes called graph associahedra. For a link in the 3-sphere, we obtain a sequence of bigraded vector spaces, interpolating between the reduced, Z/2Z Khovanov homology and a version of the monopole Floer homology of the branched double cover. This perspective also yields a simple, topological proof that odd Khovanov homology is mutation invariant. Paper reference: arxiv.org/abs/0903.3746, arxiv.org/abs/0909.0816
   
Differential Geometry and Geometric Analysis Seminar
Topic: Center of mass and constant mean curvature foliations in general relativity
Presenter: Lan-Hsuan Huang, Columbia University
Date:  Friday, October 30, 2009, Time: 3:00 p.m., Location: Fine Hall 314
Abstract: We will discuss the existence and uniqueness of the foliation by stable spheres with constant mean curvature for asymptotically flat manifolds satisfying the Regge-Teitelboim condition at infinity. We will first introduce the background and then discuss how the foliation relates to the concept of center of mass in general relativity.
   
Joint IAS/Princeton University Number Theory Seminar ***Please note special date, time, and location
Topic: Modularity lifting for n-dimensional ordinary Galois representations
Presenter: David Geraghty, Harvard
Date:  Friday, October 30, 2009, Time: 4:00 p.m., Location: Fine Hall 322
Abstract: I will discuss a generalization of the modularity lifting theorems of Clozel, Harris and Taylor to the case of ordinary Galois representations. The result is obtained by applying the Taylor-Wiles method (with innovations due to Kisin and Taylor) over a Hida family. A key step is to construct an appropriate ordinary lifting ring and determine its irreducible components.
   
NOVEMBER 2009
   
Geometry, Representation Theory, and Moduli Seminar
Topic: TBA
Presenter: L. Borisov, Rutgers University
Date:  Monday, November 2, 2009, Time: 4:30 p.m., Location: Fine Hall 314
   
Joint IAS/Princeton University Number Theory Seminar
Topic: Mean values with GL(2) times GL(3) functions
Presenter: M. Young, TAMU
Date:  Thursday, November 5, 2009, Time: 4:30 p.m., Location: IAS S-101
   
PACM Colloquium
Topic: Geometry and Analysis of point sets in high dimensions
Presenter: Mauro Maggioni, Duke University
Date:  Monday, November 9, 2009, Time: 4:00 p.m., Location: Fine Hall 214
Abstract: The analysis of high dimensional data sets is useful in a large variety of applications, from machine learning to dynamical systems: data sets are often modeled as low-dimensional, noisy data sets embedded in high-dimensional spaces; dynamical systems often have very high-dimensional state spaces but sometimes interesting dynamics occurs on low-dimensional sets. We discuss several problems associated with the analysis of the geometry of such sets, and with the approximation of functions on such sets, together with some solutions: in particular we discuss how to construct random walks on such data sets and perform multiscale analysis of them and their applications (especially to machine learning); how to construct robust coordinate systems for data sets; how to estimate reliably the intrinsic dimensionality of the data when only few noisy samples are available.
   
Group Actions Seminar
Topic: TBA
Presenter: Nimish Shah, Ohio State University
Date:  Tuesday, November 10, 2009, Time: 12:30 p.m., Location: Fine Hall 322
   
Algebraic Geometry Seminar
Topic: TBA
Presenter: Matt DeLand, Stony Brook University
Date:  Tuesday, November 10, 2009, Time: 4:30 p.m., Location: Fine Hall 322
   
Mathematical Physics Seminar
Topic: A variational model for crystals with defects
Presenter: Mathieu Lewin, Université de Cergy-Pontoise
Date:  Tuesday, November 10, 2009, Time: 4:30 p.m., Location: Jadwin 343
Abstract: This talk will be devoted to the reduced Hartree-Fock model for crystals with defects.
The main idea is to describe at the same time the electrons bound by the defect and the (nonlinear) behavior of the infinite crystal. This leads to a bounded-below nonlinear functional whose variable is however an operator of infinite-rank.
I will provide the correct functional setting for this functional, state the existence of global-in-time solutions to the associated time-dependent Schrödinger equation, and discuss the existence, the properties and the stability of bound states. In particular I will define the dielectric permittivity of the perfect crystal and relate this to some properties of ground states. This is a review of joint works with Eric Cancès and Amélie Deleurence (Ecoledes Ponts, Paris).
   
Department Colloquium
Topic: A model-theoretic approach to certain diophantine problems
Presenter: Jonathan Pila, University of Bristol
Date:  Wednesday, November 11, 2009, Time: 4:30 p.m., Location: Fine Hall 314
Abstract: I will describe some results and problems about the distribution of rational points on certain non-algebraic sets in real space. They find their natural setting in the model-theoretic notion of an `o-minimal structure over the real numbers'. I will describe a result joint with Alex Wilkie in this setting. A surprising strategy, proposed by Umberto Zannier, uses this result to approach diophantine problems in the Manin-Mumford-Andre-Oort circle of conjectures. I will describe some implementations of this strategy highlighting the use of o-minimality at different junctures, and discuss its prospects.
   
Discrete Mathematics Seminar
Topic: TBA
Presenter: Andrew King, Columbia University
Date:  Thursday, November 12, 2009, Time: 2:15 p.m., Location: Fine Hall 224
   
Joint IAS/Princeton University Number Theory Seminar
Topic: On the areas of rational triangles or How did Euler (and how can we) solve xyz(x+y+z) = a
Presenter: Noam Elkies, Harvard University
Date:  Thursday, November 12, 2009, Time: 4:30 p.m., Location: Fine Hall 214
Abstract: By Heron's formula there exists a triangle of area $\sqrt{a}$ all of whose sides are rational if and only if $a > 0$ and $xyz(x + y + z) = a$ for some rationals $x, y, z$. In a 1749 letter to Goldbach, Euler constructed infinitely many such $(x, y, z)$ for any rational $a$ (positive or not), remarking that it cost him much effort but not explaining his method. We suggest one approach, using only tools available to Euler, that he might have taken, and use it to construct several other infinite families of solutions. Then we reconsider the problem as a question in arithmetic geometry: $xyz(x+y+z) = a$ gives a K3 surface, and each family of solutions is a singular rational curve on that surface defined over {\bf Q}. The structure of that Néron--Severi group of that K3 surface explains why the problem is unusually hard. Along the way we also encounter the Niemeier lattices (the even unimodular lattices in ${\bf R}^{24}$) and the non-Hamiltonian Petersen graph.
   
Differential Geometry and Geometric Analysis Seminar
Topic: TBA
Presenter: Rick Schoen, Stanford University
Date:  Friday, November 13, 2009, Time: 3:00 p.m., Location: Fine Hall 314
   
Joint Columbia-Courant-Princeton University Algebraic Geometry Seminar *** Please note special date, time, and location
Topic: Analogue of the Narasimhan-Seshadri theorem in higher dimensions and holonomy
Presenter:

Vikraman Balaji, Chennai Mathematical Institute

Date:  Friday, November 13, 2009, Time: 3:00 p.m., Location: Fine Hall 214
Abstract: We will discuss some recent work on natural analogues of the Narasimhan-Seshadri theorem on higher dimensional varieties with some applications to stable bundles on surfaces. The classical result related stability of bundles on projective smooth curves with irreducible unitary representations of the fundamental group. Analogues of holonomy groups and their representations play the corresponding role.
   
Joint Columbia-Courant-Princeton University Algebraic Geometry Seminar *** Please note special date, time, and location
Topic: Mirror symetry for del Pezzo surfaces
Presenter:

Tony Pantev, University of Pennsylvania

Date:  Friday, November 13, 2009, Time: 4:30 p.m., Location: Fine Hall 214
Abstract: I will discuss the general mirror symmetry question for del Pezzo surfaces in a setup that goes beyond the Hori-Vafa ansatz. I will describe the mirror map explicitly and will describe non-trivial consequences of homological mirror symmetry that can be proven directly. This is a joint work with Auroux, Katzarkov and Orlov.
   
Analysis Seminar
Topic: Astala's conjecture on Hausdorff measure distortion under planar quasiconformal mappings and related removability problems
Presenter: Ignacio Uriarte-Tuero, Michigan State University
Date:  Monday, November 16, 2009, Time: 4:00 p.m., Location: Fine Hall 110
Abstract: In his celebrated paper on area distortion under planar quasiconformal mappings (Acta 1994) (for which he received the Salem prize), Astala proved that if $E$ is a compact set of Hausdorff dimension $d$ and $f$ is $K$-quasiconformal, then $fE$ has Hausdorff dimension at most $d' = \frac{2Kd}{2+(K-1)d}$, and that this result is sharp. He conjectured (Question 4.4) that if the Hausdorff measure $\mathcal{H}^d (E)=0$, then $\mathcal{H}^{d'} (fE)=0$. This conjecture was known to be true if $d'=0$ (obvious), $d'=2$ (Ahlfors), and $d'=1$ (Astala, Clop, Mateu, Orobitg and UT, Duke 2008.) The approach in the last mentioned paper does not generalize to other dimensions. UT showed that Astala's conjecture is sharp in the class of all Hausdorff gauge functions (IMRN, 2008). Lacey, Sawyer and UT jointly proved completely Astala's conjecture in all dimensions (Acta, 2009?) The proof uses Astala's 1994 approach, geometric measure theory, and new weighted norm inequalities for Calder\'{o}n-Zygmund singular integral operators which cannot be deduced from the classical Muckenhoupt $A_p$ theory. These results are intimately related to removability problems for various classes of quasiregular maps. I will particularly mention sharp removability results for bounded $K$-quasiregular maps recently obtained in joint work of Tolsa and UT. The talk will be self-contained.
   
PACM Colloquium
Topic: Testable New Theory about Early-Universe Density Fluctuations and Origins of Solar Systems: Applied-Probability and Quantum-Physics Aspects
Presenter: Erik Vanmarcke, Civil and Environmental Engineering
Date:  Monday, November 16, 2009, Time: 4:00 p.m., Location: Fine Hall 214
Abstract: The talk will summarize, with a focus on applied-probability aspects, the main findings, testable predictions and research opportunities stemming from a new probabilistic model of how complex patterns of energy-density fluctuations may have arisen during the inflation phase of the Big Bang. Based on first (quantum-physical) principles and requiring a minimum number of (observationally-accessible) parameters, the "embryonic inflation model" yields a coherent set of testable (hence falsifiable) hypotheses about the formation, evolution, composition, internal structure and cosmic environment of galaxies, stars and planets, and is consistent with key findings from observations of the Cosmic Microwave Background (CMB). Implying a robust alternative (and challenge) to the dual paradigm of spatially-uniform light-element primordial nucleosynthesis and stellar "recycling" of matter as the sole mechanism of heavy-element production, the theory holds the promise of integrating astrophysical and planetary sciences with cosmology and galaxy formation in a coherent evolutionary framework. Observations indicating overall cosmic flatness, the existence of an accelerating component, dark matter and dark energy all fit, in quantifiable and testable ways, into the framework of the theory.
   
Geometry, Representation Theory, and Moduli Seminar
Topic: TBA
Presenter: Z. Yun, IAS
Date:  Monday, November 16, 2009, Time: 4:30 p.m., Location: Fine Hall 314
   
Group Actions Seminar
Topic: Inhomogeneous quadratic forms
Presenter: Amir Mohammadi, University of Chicago
Date:  Tuesday, November 17, 2009, Time: 12:30 p.m., Location: Fine Hall 322
Abstract: We will address a recent join work with G. Margulis on a quantitative version of the Oppenheim conjecture for inhomogeneous quadratic forms. This generalizes the previous works of Eskin, Margulis and Mozes in the homogeneous setting also the work of J. Marklof.
   
Algebraic Geometry Seminar
Topic: TBA
Presenter: Paul Hacking, University of Massachusetts Amherst
Date:  Tuesday, November 17, 2009, Time: 4:30 p.m., Location: Fine Hall 322
   
Mathematical Physics Seminar
Topic: The emergence of a giant vortex in a fast rotating Bose gas.
Presenter: Jakob Yngvason, University of Vienna
Date:  Tuesday, November 17, 2009, Time: 4:30 p.m., Location: Jadwin 343
Abstract: A Bose gas in fast rotation normally exhibits a growing number of vortices of unit strength if the angular velocity is increased. In an anharmonic trap at sufficiently high velocity, however, a phase transition is expected: Vortices in the bulk should disappear and all vorticity become concentrated in a region where the density is very low. Moreover, the critical velocity for the transition is expected to increase with on the interaction strength in a definite manner. In the lecture rigorous results on this behavior within two-dimensional Gross-Pitaevskii theory will be presented. This is joint work with Michele Correggi and Nicolas Rougerie.
   
Department Colloquium
Topic: Abelian sandpile model and self-similar groups
Presenter: Tatiana Smirnova, University of Geneva
Date:  Wednesday, November 18, 2009, Time: 4:30 p.m., Location: Fine Hall 314
Abstract: The sandpile model was introduced in 1987 by physisists Bak, Tang and Wiesenfeld as a tool to study what they called {\it the self-organized criticality} - spontaneous appearance of power laws or fractal interfaces, observed in some natural phenomena. The mathematical study of the model was initiated a couple of years later by Deepak Dhar. It begins with a simple cellular automaton (also known in combinatorics under the name of {\it chip-firing game} on a finite graph, and leads to interesting long time and large volume limit dynamics when considered on increasing sequences of graphs. After an introduction to the Abelian sandpile model (ASM), I will show that the recent theory of self-similar groups (also known as automata groups) is a natural source of such families of graphs, giving rise to new interesting asymptotics and providing new evidence for the limit behaviour of the ASM.
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: TBA
Presenter: Lai-Sang Young, Courant Institute
Date:  Thursday, November 19, 2009, Time: 2:00 p.m., Location: Fine Hall 401
   
Discrete Mathematics Seminar
Topic: TBA
Presenter: Peter Winkler, Dartmouth College
Date:  Thursday, November 19, 2009, Time: 2:15 p.m., Location: Fine Hall 224
   
PACM Colloquium
Topic: Solving High-Dimensional Stochastic Optimization Problems using Approximate Dynamic Programming
Presenter: Warren Powell, ORFE
Date:  Monday, November 23, 2009, Time: 4:00 p.m., Location: Fine Hall 214
Abstract: There are many stochastic resource allocation problems arising in transportation, energy and health that involve high-dimensional state and action variables in the presence of di erent forms of uncertainty. These might involve discrete or continuous resources, and generally involve vectors of random variables that preclude exact computation of expectations. I will also describe our research into the important \exploration vs. exploitation" problem that arises in approximate dynamic programming, where we have the ability to choose the next state we will visit.
   
Geometry, Representation Theory, and Moduli Seminar
Topic: TBA
Presenter: D. Zakharov, Columbia University
Date:  Monday, November 23, 2009, Time: 4:30 p.m., Location: Fine Hall 314
   
Group Actions Seminar
Topic: TBA
Presenter: Zhiren Wang, Princeton University
Date:  Tuesday, November 24, 2009, Time: 12:30 p.m., Location: Fine Hall 322
   
Algebraic Geometry Seminar
Topic: TBA
Presenter: Tommase deFernex, University of Utah
Date:  Tuesday, November 24, 2009, Time: 4:30 p.m., Location: Fine Hall 322
   
Mathematical Physics Seminar
Topic: TBA
Presenter: Alexander Sodin, Tel Aviv University
Date:  Tuesday, November 24, 2009, Time: 4:30 p.m., Location: Jadwin 343
   
Department Colloquium
Topic: Concentration Compactness for critical Wave Maps
Presenter: Joachim Krieger, University of Pennsylvania
Date:  Wednesday, November 25, 2009, Time: 4:30 p.m., Location: Fine Hall 314
Abstract: This talk will discuss a recent result on global regularity and asymptotic behavior of large critical wave maps with hyperbolic target, obtained jointly with W. Schlag. The proof relies on an adaptation of the recently developed method of Kenig-Merle to the case of systems of wave equations, as well as the harmonic analytic methods devised by Klainerman-Machedon, Tataru and Tao.
   
PACM Colloquium
Topic: Looking over the painter’s shoulder
Presenter: Joris Dik, Delft University of Technology, Netherlands
Date:  Monday, November 30, 2009, Time: 4:00 p.m., Location: Fine Hall 214
Abstractt: Just microns below their paint surface lies a wealth of information on Old Master Paintings. Hidden layers can include the underdrawing, the underpainting or compositional alterations by the artist. All too often artists simply re-used their canvases and painted a new composition on top. Thus, a look /through /the paint layer provides a look /over/ the painter’s shoulder. I will discuss case different subsurface imaging techniques and present case studies from the work of Vincent van Gogh and Rembrandt.
   

DECEMBER 2009

   
Group Actions Seminar
Topic: TBA
Presenter: Martin Kassabov, Cornell University and IAS
Date:  Tuesday, December 1, 2009, Time: 12:30 p.m., Location: Fine Hall 322
   
Algebraic Geometry Seminar
Topic: TBA
Presenter: Ekaterina Amerik, IAS
Date:  Tuesday, December 1, 2009, Time: 4:30 p.m., Location: Fine Hall 322
   
Mathematical Physics Seminar
Topic: TBA
Presenter: Vieri Mastropietro, Univ. Rome II
Date:  Tuesday, December 1, 2009, Time: 4:30 p.m., Location: Jadwin 343
   
Discrete Mathematics Seminar *** Please note special day
Topic: TBA
Presenter: Maria Chudnovsky, Columbia University
Date:  Wednesday, December 2, 2009, Time: 2:15 p.m., Location: Fine Hall 224
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: Unbiased Random Perturbations of Navier-Stokes Equation
Presenter: Boris Rozovsky, Lefschetz Center for Dynamical Systems, Brown University
Date:  Thursday, December 3, 2009, Time: 2:00 p.m., Location: Fine Hall 401
Abstract: A random perturbation of a deterministic Navier-Stokes equation is considered in the form of an Stochastic PDE with Wick product in the nonlinear term. The equation is solved in the space of generalized stochastic processes using the Cameron-Martin version of the Wiener chaos expansion. The generalized solution is obtained as an inverse of solutions to corresponding quantized equations.
An interesting feature of this type of perturbation is that it preserves the mean dynam- ics: the expectation of the solution of the perturbed equation solves the underlying deterministic Navier-Stokes equation. From the stand point of a statistician it means that the perturbed model is unbiased. The talk is based on a joint work with R. Mikulevicius.
   
Differential Geometry and Geometric Analysis Seminar
Topic: Conformal Structure of Minimal Surfaces with Finite Topology
Presenter: Christine Breiner, MIT
Date:  Friday, December 4, 2009, Time: 3:00 p.m., Location: Fine Hall 314
Abstract: The recent construction of a genus-one helicoid verified the existence of a second example of a complete, embedded minimal surface with finite topology and infinite total curvature in $\mathbb{R}3$. We determine the conformal structure and asymptotic Weierstrass data of all surfaces with these properties. Using this structure and the asymptotics, in the case $g=1$ we establish the existence of an orientation preserving isometry. This is joint work with Jacob Bernstein
   
PACM Colloquium
Topic: Imaging Techniques and the Rejuvenation of Artwork
Presenter: Roy S. Berns, Munsell Color Science Laboratory, Chester F. Carlson Center for Imaging Science, Rochester Institute of Technology, USA
Date:  Monday, December 7, 2009, Time: 4:00 p.m., Location: Fine Hall 214
Abstract: Advances in digital imaging within the visible spectrum enable the accurate color rendering of artwork. It is possible to generate a colorimetric image with high spatial resolution and high image quality (appropriate sharpness and low noise). When the number of sensor channels exceeds three, it is also possible to generate spectral images. Spectral images can be used to calculate colorimetric images for any illuminant and observer pair, to evaluate color inconstancy, as an aid in retouching (i.e., restorative inpainting), for pigment mapping, and to improve printed reproductions. These digital images, of course, record the color and spectra of the artwork in its current condition. Depending on how the artwork has aged, its color may bear little resemblance to its appearance when first executed. This can dramatically affect the analysis of the painting in terms of its historical context and understanding the artist's working methods. A variety of techniques can be used to determine such color changes including analysing cross-sections, finding protected areas and identical materials that retain their color, early photographic records, and descriptions by art critics and connoisseurs at the time of creation. Having determined that a color change has occurred, it is possible to rejuvenate the colors of a digital image by using the principles of instrumental-based color matching. These principles are used to determine pigments and their concentrations that when mixed, match a particular color. This is equivalent to pigment mapping. The digital rejuvenation is performed by either replacing the spectral properties of the changed pigment with one that hasn't changed or increasing the concentration of a pigment that has faded. These rejuvenated images, while speculative, provide important and interesting new insights. This presentation will review research by the author in digital rejuvenation using examples by Vincent Van Gogh and Georges Seurat.
   
Group Actions Seminar
Topic: TBA
Presenter: Uri Shapira, Hebrew University
Date:  Tuesday, December 8, 2009, Time: 12:30 p.m., Location: Fine Hall 322
   
Algebraic Geometry Seminar
Topic: TBA
Presenter: Roya Beheshti Zavareh, Washington University in St. Louis
Date:  Tuesday, December 8, 2009, Time: 4:30 p.m., Location: Fine Hall 322
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: TBA
Presenter: Michael Boshernitzan, Rice University
Date:  Thursday, December 10, 2009, Time: 2:00 p.m., Location: Fine Hall 401
   
Differential Geometry and Geometric Analysis Seminar
Topic: TBA
Presenter: Song Sun, Wisconsin
Date:  Friday, December 11, 2009, Time: 3:00 p.m., Location: Fine Hall 314
   
Discrete Mathematics Seminar
Topic: TBA
Presenter: Alexandra Ovetsky Fradkin, Princeton University
Date:  Thursday, December 17, 2009, Time: 2:15 p.m., Location: Fine Hall 224
   
Topology Seminar
Topic: TBA
Presenter: Peter Ozsvath, Columbia University
Date:  Thursday, December 17, 2009, Time: 4:30 p.m., Location: Fine Hall 314