SEMINARS
Updated: 4-18-2007
   
APRIL 2007
   
Sato-Tate Seminar
Topic: Bigness and auxiliary primes
Presenter: Brian Conrad, University of Michigan and Columbia University
Date:  Wednesday, April 18, 2007, Time: 1:30 p.m., Location: Fine 314
   
Discrete Mathematics Seminar
Topic: Pfaffian orientations of graphs
Presenter: Serguei Norine, Georgia Tech
Date:  Wednesday, April 18, 2007, Time: 2:15 p.m., Location: Fine 224
Abstract: See http://www.math.princeton.edu/~bsudakov/norine2007-spring.pdf
   
Geometry, Representation Theory, and Moduli Seminar
Topic: The Gromov-Witten invariants of [Sym2 CP2]
Presenter: J. Wise, Brown University
Date:  Wednesday, April 18, 2007, Time: 3:00 p.m., Location: Fine 214
   
Department Colloquium
Topic: Billiards and dynamics over moduli space
Presenter: Curtis T McMullen, Harvard University
Date:  Wednesday, April 18, 2007, Time: 4:30 p.m., Location: Fine 314
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: Poincare Lectures I
Presenter: Aaron Naber, Princeton University
Date:  Thursday, April 19, 2007, Time: 2:00 p.m., Location: Fine 401
Abstract: We relate the recent advances made by Perelman in the Ricci Flow and their application to the proof of the Poincare Conjecture. The proof is broken into three parts: The existence and classification of singularity dilations of the Ricci Flow, the definition and long time existence of the Ricci Flow with Surgery, and the finite time extension of such a flow. After an overview of the proof we will focus on the singularity classification in dimension three.
   
Princeton University and Institute for Advanced Study Number Theory Seminar
Topic: On a conjecture of Greenberg on Iwasawa invariants of totally real number fields
Presenter: Conjeeveram Rajan, IAS
Date:  Thursday, April 19, 2007, Time: 4:30 p.m., Location: IAS SH-101
Abstract:

We show that Leopoldt's conjecture for totally real number fields implies Greenberg's conjecture on the uniform boundedness of the $p$-primary part of the class groups of the finite extensions along the cyclotomic tower of a totally real number field.

   
Topology Seminar
Topic: Minimal-complexity surfaces in pretzel link complements
Presenter: Joan Licata, Yale University
Date:  Thursday, April 19, 2007, Time: 4:30 p.m., Location: Fine 314
   
Geometric Flows and Related Topics Workshop
Topic: The hypoelliptic Dirac operator
Presenter: Jean-Michel Bismut, U Paris-Sud and NYU
Date:  Friday, April 20, 2007, Time: 2:00 p.m., Location: Fine 214
   
Geometric Flows and Related Topics Workshop
Topic: Holomorphic Kahler-Einstein metrics and Kahler-Ricci flow
Presenter: Jian Song, Johns Hopkins University
Date:  Friday, April 20, 2007, Time: 3:15 p.m., Location: Fine 314
   
Geometric Flows and Related Topics Workshop
Topic: Singularities of harmonic maps, minimal surfaces and mean curvature flow
Presenter: Neshan Wickramasekera, UCSD
Date:  Friday, April 20, 2007, Time: 4:30 p.m., Location: Fine 314
   
Geometric Flows and Related Topics Workshop
Topic: New Ricci flow invariant curvature conditions in large dimensions
Presenter: Burkhard Wilkiing, University of Munster
Date:  Saturday, April 21, 2007, Time: 10:00 a.m., Location: Fine 314
   
Geometric Flows and Related Topics Workshop
Topic: Curve shortening and the topology of closed geodesics on Finsler surfaces
Presenter: Sigurd Angenent, University of Wisconsin
Date:  Saturday, April 21, 2007, Time: 11:15 a.m., Location: Fine 314
   
Geometric Flows and Related Topics Workshop
Topic: A Harnack inequality for the conjugate heat equation under Ricci flow
Presenter: Qi Zhang, UC Riverside
Date:  Saturday, April 21, 2007, Time: 2:00 p.m., Location: Fine 314
   
Geometric Flows and Related Topics Workshop
Topic: Dimensional reduction and long-time behavior of Ricci flow
Presenter: John Lott, University of Michigan
Date:  Saturday, April 21, 2007, Time: 3:15 p.m., Location: Fine 314
   
Special Joint Analysis and Ergodic Theory Seminar
Topic: Limiting distributions of expanding translates of a curve on SO(n,1)/Γ
Presenter: Nimish A. Shah, Tata Institut
Date:  Monday, April 23, 2007, Time: 4:00 p.m., Location: Fine 110
Abstract: See http://www.math.princeton.edu/~seminar/2006-07-sem/nimish-abstract.pdf
   
PACM Colloquium
Topic: Heterogeneous Lipid Bilayers: Evolving Microstructures in Biology
Presenter: Mikko Haataja, MAE, Princeton University
Date:  Monday, April 23, 2007, Time: 4:00 p.m., Location: Fine 214
Abstract:

The design and processing of materials with novel physical and mechanical properties requires a fundamental understanding of the connections between processing, microstructure, and properties. For example, mechanical properties in pure metals and alloys can be varied by manipulating the polycrystalline grain size or the size of the compositional domains through heat treatment, while elastic strain provides a way to tune the optical properties of self-assembled quantum dots during growth. In an analogous manner, the biological function of cell membranes is strongly affected by the details of the local "microstructure".

Typically, microstructural evolution takes place across multiple length and time scales, ranging from atomistic to mesoscopic ones. In this talk I will describe our recent efforts in developing physically-based, coarse-grained continuum models, which bridge the atomistic and mesoscopic scales, to elucidate lateral organization and non-equilibrium dynamics of heterogeneous lipid bilayers. In particular, I will focus on spatially organized, dynamic heterogeneities in the local lipid composition ("lipid rafts") which have been implicated in many important cellular processes including signal transduction, membrane trafficking, cytoskeleton organization, and pathogen entry.

   
Algebraic Geometry Seminar
Topic: Free absolute Galois groups
Presenter: David Harbater, University of Pennsylvania
Date:  Tuesday, April 24, 2007, Time: 4:30 p.m., Location: Fine 322
Abstract: A conjecture of Shafarevich says that the absolute Galois group of the maximal abelian extension of the rationals is free. A function field analog of the conjecture, for curves over finite fields, was proven by F. Pop and the speaker, using patching methods in rigid or formal geometry. This talk considers a two-dimensional local analog, showing the freeness of the absolute Galois group of the maximal abelian extension of k((x,y)) for k separably closed. This relies on patching methods, the structure of profinite groups, and a result of Colliot-Thelene, Parimala and Ojanguren.
   
Operations Research and Financial Engineering Seminar
Topic: A Duality Theory for Set-Valued Convex Functions
Presenter: Andreas Hamel, University Halle-Wittenberg
Date:  Tuesday, April 24, 2007, Time: 4:30 p.m., Location: E-219, E-Quad
Abstract:

Duality for extended real-valued convex functions is a well-studied, even classical subject based on works of Fenchel, Moreau, Rockafellar, among many others. A corresponding satisfying theory for functions mapping into the power set of a partially ordered locally convex space is still missing. Such a theory seems to be very desirable since it has already been observed e.g. by Luc in 1989 that the dual of a convex vector optimization problem ’is set-valued in nature’. Moreover, the concept of convex set-valued risk measures has been defined recently in financial mathematics which asks for a corresponding dual representation theory.

We shall present a duality concept that is based on a new notion of affine minorants for set-valued functions and show that almost every concept (e.g. properness, sublinearity, conjugates, inf-convolution) and result (e.g. biconjugation and Fenchel-Rockafellar duality theorems) known in the scalar case can be formulated within this new framework. A special feature of the methodology is that proofs do not rely on the corresponding scalar theory – as in almost every duality theory for vector optimization problems. On the other hand, every main result can equivalently be expressed as a result for a family of scalar problems. Finally, we shall show the theory at work when applied to linear vector optimization problems and to set-valued risk measures.

   
Discrete Mathematics Seminar
Topic: TBA
Presenter: Assaf Naor, NYU
Date:  Wednesday, April 25, 2007, Time: 2:15 p.m., Location: Fine 224
   
Department Colloquium
Topic: TBA
Presenter: Jacob Rasmussen, Princeton University
Date:  Wednesday, April 25, 2007, Time: 4:30 p.m., Location: Fine 314
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: Poincare Lectures II
Presenter: Aaron Naber, Princeton University
Date:  Thursday, April 26, 2007, Time: 2:00 p.m., Location: Fine 401
Abstract: We relate the recent advances made by Perelman in the Ricci Flow and their application to the proof of the Poincare Conjecture. The proof is broken into three parts: The existence and classification of singularity dilations of the Ricci Flow, the definition and long time existence of the Ricci Flow with Surgery, and the finite time extension of such a flow. After an overview of the proof we will focus on the singularity classification in dimension three.
   
Topology Seminar
Topic: Heegaard Splittings and Hyperbolic Geometry
Presenter: Hossein Namazi, Princeton University
Date:  Thursday, April 26, 2007, Time: 4:30 p.m., Location: Fine 314
Abstract: How does a hyperbolic 3-manifold look like? We speak about an approach to answer this question which uses the combiatorial data provided by a Heegaard splitting.
   
Symplectic Geometry Seminar
Topic: Vanishing of the fundamental class of displaceable Lagrangian submanifolds
Presenter: Peter Albers, NYU
Date:  Friday, April 27, 2007, Time: 2:00 p.m., Location: Fine 214
Abstract: In this talk I will sketch a proof of the following theorem. The fundamental class of a displaceable monotone Lagrangian submanifold vanishes. This proof uses an geometric argument and Hamiltonian Floer homology. Afterwards I will put this into a more conceptual context involving Lagrangian and Hamiltonian Floer homology and their interplay. This yields another (slightly more general proof of the aforementioned theorem and some further corollaries concerned with topological properties of Lagrangian submanifolds.
   
Differential Geometry and Geometric Analysis Seminar
Topic: TBA
Presenter: Meijun Zhu, University of Oklahoma
Date:  Friday, April 27, 2007, Time: 3:00 p.m., Location: Fine 314
   
Differential Geometry and Geometric Analysis Seminar *** Please note special time
Topic: The Riemannian Penrose Inequality in dimensions less than 8
Presenter: Dan Lee, Duke University
Date:  Friday, April 27, 2007, Time: 4:00 p.m., Location: Fine 314
Abstract: The Riemannian Penrose Inequality was first proved in three dimensions in 1997 by G. Huisken and T. Ilmanen for the case of a single black hole.  In 1999, H. Bray extended this result to the general case of multiple black holes using a different technique.  I will discuss joint work with H. Bray on extending Bray's technique to dimensions less than 8.
   
MAY 2007
   
Algebraic Geometry Seminar
Topic: Gerby localization and GW invariants of [C^N/Z_r]
Presenter: Charles Cadman, University of Michigan
Date:  Tuesday, May 1, 2007, Time: 4:30 p.m., Location: Fine 322
Abstract: An important conjecture in Gromov-Witten theory relates the quantum potential of an orbifold with that of a crepant resolution of its coarse moduli space. Recent work has focused on orbifolds of the form [C^N/G], where G is a finite group acting linearly on C^N. I will discuss two approaches to computing the orbifold Gromov-Witten invariants, one of which is joint work with Arend Bayer and the other with Renzo Cavalieri.
   
Operations Research and Financial Engineering Seminar
Topic: TBA
Presenter: Rong Chen, University of Illinois at Chicago
Date:  Tuesday, May 1, 2007, Time: 4:30 p.m., Location: E-219, E-Quad
   
Department Colloquium
Topic: TBA
Presenter: Tamar Ziegler, University of Michigan
Date:  Wednesday, May 2, 2007, Time: 4:30 p.m., Location: Fine 314
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: Bulk Universality and Related Properties of Hermitian Matrix Models
Presenter: L.Pastur, Institute for Low Temperatures, Kharkiv, Ukraine
Date:  Thursday, May 3, 2007, Time: 2:00 p.m., Location: Fine 401
Abstract: We give a new proof of universality properties in the bulk of spectrum of the hermitian matrix models, assuming that the potential that determines the model is globally $C^{2}$ and locally $C^{3}$ function. The proof is based on the orthogonal polynomial techniques but does not use asymptotics of orthogonal polynomials. Rather, we obtain the $sin$-kernel as a unique solution of a certain non-linear integro-differential equation that follows from the determinant formulas for the correlation functions. We also present a simplified and strengthened version of the proof of existence and properties of the limiting Normalized Counting Measure of eigenvalues.
   
Topology Seminar
Topic: TBA
Presenter: Doug Park, University of Waterloo
Date:  Thursday, May 3, 2007, Time: 4:30 p.m., Location: Fine 314
   
Differential Geometry and Geometric Analysis Seminar
Topic: TBA
Presenter: Guozheng Lu, Wayne State University
Date:  Friday, May 4, 2007, Time: 3:00 p.m., Location: Fine 314
   
Operations Research and Financial Engineering Seminar
Topic: TBA
Presenter: Frank Heyde, MLU Halle-Wittenberg
Date:  Tuesday, May 8, 2007, Time: 4:30 p.m., Location: E-219, E-Quad
   
Ergodic Theory and Statistical Mechanics Seminar
Topic: Circle rotations and the shrinking target properties
Presenter: Jim Tseng, Brandeis University
Date:  Thursday, May 10, 2007, Time: 2:00 p.m., Location: Fine 401
Abstract: The shrinking target properties are related to recurrence. We will motivate and present definitions of these properties. We will also give a necessary and sufficient condition for a circle rotation to have the s-exponent monotone shrinking target property (sMSTP), and, thereby we generalize a result for s = 1 that was established by J. Kurzweil and rediscovered by B. Fayad. We will give a detailed sketch of the proof. Finally, we will apply our technique to give a new, very short, proof of the logarithm law for irrational rotations.
   
Symplectic Geometry Seminar
Topic: TBA
Presenter: Robert Lipshitz, Columbia University
Date:  Friday, May 11, 2007, Time: 2:00 p.m., Location: Fine 214
   
Differential Geometry and Geometric Analysis Seminar
Topic: TBA
Presenter: Jih-Hsin, Academica Sinica
Date:  Friday, May 11, 2007, Time: 3:00 p.m., Location: Fine 314