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OCTOBER 2010 |
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Statistical Mechanics Seminar |
Topic: |
From microscopic hamiltonian dynamics to heat equation |
Presenter: |
Stefano Olla, Universite Paris-Dauphine |
Date: |
Wednesday, October 20, 2010, Time: 2:00 p.m., Location: Jadwin Hall 343 |
Abstract: |
One of the main problems in non-equilibrium statistical mechanics is to derive, by space-time rescaling, macroscopic irreversible diffusive evolution for the co nserved quantities of an (large) hamiltonian system. I will describe the mathematical setup of the problem, and some recent progress when the hamiltonian dynamics is perturbed by energy conserving stochastic collisions. |
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Department Colloquium |
Topic: |
Rearrangement and convection |
Presenter: |
Yann Brenier, University of Nice Sophia Antipolis |
Date: |
Wednesday, October 20, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
Abstract: |
Rearrangement theory is about reorganizing a given function (or map) in some specific order (monotonicity, cycle monotonicity etc...). This is somewhat similar to the convection phenomenon in fluid mechanics, where fluid parcels are continuously reorganized in a stabler way (heavy fluid at bottom and light fluid at top). Convection theory is one of the most important piece of geo-sciences, related to weather forecasting, oceanography, volcanism, earthquake etc... In our talk, we make these analogies more precise by analyzing the Navier-Stokes equations with buoyancy and Coriolis forces. We will see how these approximations are related to the concept, well known in optimal transport theory, of rearrangement of maps as gradient of convex functions. |
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Symplectic Geometry Seminar |
Topic: |
Schrodinger equation, deformation theory and tt^* geometry |
Presenter: |
Huijun Fan, Beijing University |
Date: |
Thursday, October 21, 2010, Time: 1:30 p.m., Location: Fine Hall 601 |
Abstract: |
I will talk about my recent work on the deformation theory of Schrodinger equations. This is an attempt to construct the rigorous mathematical foundation for topological B model, which has tight relation to the deformation theory of complex structure and the singularity theory. |
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Ergodic Theory and Statistical Mechanics Seminar |
Topic: |
From random tilings to representation theory |
Presenter: |
Vadim Gorin, Moscow State University |
Date: |
Thursday, October 21, 2010, Time: 2:00 p.m., Location: Fine Hall 401 |
Abstract: |
Lozenge tilings of planar domains provide a simple, yet sophisticated model of random surfaces. Asymptotic behavior of such models has been extensively studied in recent years.
We will start from recent results about q-distributions on tilings of a hexagon or, equivalently, on boxed plane partitions. (This part is based on the joint work with A.Borodin and E.Rains).
In the second part of the talk we will explain how representation theory of the infinite-dimensional unitary group is related to random lozenge tilings with a certain Gibbs property. We will discuss applications of this correspondence and results on the classification of Gibbs measures on tilings of the half-plane. |
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Discrete Mathematics Seminar |
Topic: |
The size Ramsey number of a directed path |
Presenter: |
Ido Ben-Eliezer, Tel-Aviv University |
Date: |
Thursday, October 21, 2010, Time: 2:15 p.m., Location: Fine Hall 224 |
Abstract: |
Given a graph H, the size Ramsey number r_e(H,q) is the minimal number m for which there is a graph G with m edges such that every q-coloring of G contains a monochromatic copy of H. We study the size Ramsey number of the directed path of length n in oriented graphs, where no antiparallel edges are allowed. We give nearly tight bounds for every fixed number of colors. For the case of two colors we show that there are constants c_1,c_2 such that \frac{c_1 n^{2} \log n}{(\log\log n)^3} \leq r_e(P_n,2) \leq c_2 n^{2}(\log n)^2.
Joint work with Michael Krivelevich and Benny Sudakov. |
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Algebraic Topology Seminar |
Topic: |
One condition for rational hyperbolicity for moment angle complexes |
Presenter: |
Sam Gitler, CINESTAV/IAS |
Date: |
Thursday, October 21, 2010, Time: 3:00 p.m., Location: Fine Hall 322 |
Abstract: |
There is a conjecture in rational homotopy which states " If a finite dimensional space X has two indecomposable classes in the rational cohomology whose cup product is zero, then its rational homotopy has exponential growth , ie,it is hyperbolic" We verify this conjecture for the space X a moment angle complex" |
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Joint Princeton University and IAS Number Theory Seminar |
Topic: |
Expanding the scope of Hilbert irreducibility |
Presenter: |
Chris Hall, University of Wyoming |
Date: |
Thursday, October 21, 2010, Time: 4:30 p.m., Location: Fine Hall 214 |
Abstract: |
If K is the rational function field K=Q(t), then a polynomial f in K[x] can be regarded as a one-parameter family of polynomials. If f is irreducible, then a basic form of Hilbert's irreducibility theorem states that there are infinitely many parameters in Q for which the corresponding polynomial is also irreducible. Moreover, if one exploits conjectures of Mordell and Lang (proved by Faltings) one can frequently prove stronger statements, e.g. that there are only finitely many reducible specializations where the parameter lies in a quadratic extension of Q.
In this talk we will introduce an analogous theorem for an abelian variety A/K regarded as a one-parameter family of abelian varieties. More precisely, if A is (geometrically) simple and non-isotrivial over K, we will sketch an argument which shows that there are only finitely many parameters defined over a number field of bounded degree for which the corresponding abelian variety is not simple. Faltings' theorems again play a key role, but as we will explain, recent advances in expander graphs play a significant role as well. |
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Topology Seminar |
Topic: |
On local combinatorial formulae for Pontryagin classes |
Presenter: |
Alexander Gaifullin, Moscow State, Steklov Institute |
Date: |
Thursday, October 21, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
Abstract: |
The talk will be devoted to the problem of combinatorial computation of the rational Pontryagin classes of a triangulated manifold. This problem goes back to the famous work by A. M. Gabrielov, I. M. Gelfand, and M. V. Losik (1975). Since then several different approaches to combinatorial computation of the Pontryagin classes have been suggested. However, these approaches require a combinatorial manifold to be endowed with some additional structure such as smoothing or certain its discrete analogue. We suggest a new approach based on the concept of a universal local formula. This approach allows us to construct an explicit combinatorial formula for the first Pontryagin class that can be applied to any combinatorial manifold without any additional structure. |
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Differential Geometry and Geometric Analysis Seminar |
Topic: |
Lower Ricci Curvature, Convexity and Applications |
Presenter: |
Aaron Naber, MIT |
Date: |
Friday, October 22, 2010, Time: 3:00 p.m., Location: Fine Hall 314 |
Abstract: |
We prove new estimates for tangent cones along minimizing geodesics in GH limits of manifolds with lower Ricci curvature bounds. We use these estimates to show convexity results for the regular set of such limits. Applications include the proofs of several conjectures dating back to the work of Cheeger/Colding and the ruling out of certain limit spaces, including the so called generalized trumpet spaces. We construct new examples which exhibit various new behaviors and show sharpness of the new theorems. This work is joint with Toby Colding. |
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Analysis Seminar ***Please note special time |
Topic: |
Well-posedness theory for compressible Euler equations in a physical vacuum |
Presenter: |
Juhi Jang, University of California, Riverside |
Date: |
Monday, October 25, 2010, Time: 2:30 p.m., Location: Fine Hall 314 |
Abstract: |
An interesting problem in gas and fluid dynamics is to understand the behavior of vacuum states, namely the behavior of the system in the presence of vacuum. A particular interest is so called physical vacuum which naturally arises in physical problems. The main difficulty lies in the fact that the physical systems become degenerate along the boundary. I'll present the well-posedness result of 3D compressible Euler equations for polytropic gases. This is a joint work with Nader Masmoudi. |
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PACM Colloquium |
Topic: |
Feedback, Lineages and Cancer |
Presenter: |
John Lowengrub, University of California - Irvine |
Date: |
Monday, October 25, 2010, Time: 4:00 p.m., Location: Fine Hall 214 |
Abstract: |
A multispecies continuum model is developed to simulate the dynamics of cell lineages in solid tumors. The model accounts for spatiotemporally varying cell proliferation and death mediated by the heterogeneous distribution of oxygen and soluble chemical factors. Together, these regulate the rates of self-renewal and differentiation of the different cells within the lineages. As demonstrated in the talk, the feedback processes are found to play a critical role in tumor progression and the development of morphological instability. |
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Mathematical Physics Seminar |
Topic: |
Trace Formulas for Large Random d-Regular Graphs |
Presenter: |
Idan Oren, The Weizmann Institute |
Date: |
Tuesday, October 26, 2010, Time: 4:30 p.m., Location: Jadwin 343 |
Abstract: |
Trace formulas for d-regular graphs are derived and used to express the spectral density in terms of the periodic walks on the graphs under consideration. The trace formulas depend on a parameter (w) which can be tuned continuously to assign different weights to different periodic orbit contributions. At the special value w = 1, the only periodic orbits which contribute are the non back- scattering orbits, and the smooth part in the trace formula coincides with the Kesten-McKay expression. As (w) deviates from unity, non vanishing weights are assigned to the periodic walks with back-scatter, and the smooth part is modified in a consistent way. The trace formulas presented in this talk can be used as tools for showing the connection between the spectral properties of d-regular graphs and the theory of random matrices. |
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Statistical Mechanics Seminar |
Topic: |
Characterization of Lee-Yang polynomials |
Presenter: |
David Ruelle, IHES, France |
Date: |
Wednesday, October 27, 2010, Time: 2:00 p.m., Location: Jadwin Hall 343 |
Abstract: |
I shall give a characterization of the multi-affine polynomials in n variables that occur in the proof of the Lee-Yang Circle Theorem. In particular, it will be seen that the spin interactions for which the Circle Theorem holds at all temperatures must be the ferromagnetic pair interactions originally considered by Lee and Yang (i.e., for non-pair interactions, the theorem fails at some temperature!). |
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Algebraic Topology Seminar |
Topic: |
Algebraic structures from operads and moduli spaces |
Presenter: |
Ralph Kaufmann, IAS |
Date: |
Thursday, October 28, 2010, Time: 3:00 p.m., Location: Fine Hall 322 |
Abstract: |
Some classical algebraic structures like Gerstenhaber's bracket on the Hochschild complex have an operadic origin. We discuss generalizations of these operations coming from different operadic type settings. This includes geometric constructions from moduli spaces and master equations appearing in string topology and in a "pedestrian" version of string field theory. |
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Joint Princeton University and IAS Number Theory Seminar |
Topic: |
Constructing Abelian varieties over Qbar not isogenous to a Jacobian |
Presenter: |
Jacob Tsimerman, Princeton University |
Date: |
Thursday, October 28, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
Abstract: |
We discuss the following question of Nick Katz and Frans Oort: Given an Algebraically closed field K, is there an Abelian variety over K of dimension g which is not isogenous to a Jacobian? For K the complex numbers its easy to see that the answer is yes for g>3 using measure theory, but over a countable field like Qbar new methods are required. Building on work of Chai-Oort, we show that, as expected, such Abelian varieties exist for K=Qbar and g>3. We will explain the proof as well as its connection to the Andre Oort conjecture. |
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Topology Seminar |
Topic: |
Fox re-embedding and Bing submanifolds |
Presenter: |
Kei Nakamura, Temple University |
Date: |
Thursday, October 28, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
Abstract: |
Let M be an orientable closed connected 3-manifold, and Y be a connected compact 3-manifold. We show that the following two conditions are equivalent: (i) Y can be embedded in M so that the closure of the complement of the image of Y is a union of handlebodies; and (ii) Y can be embedded in M so that every embedded closed loop in M can be isotoped to lie within the image of Y. Our result can be regarded as a common generalization of Fox's reimbedding theorem (1948) and Bing's characterization of 3-sphere (1958), as well as more recent results of Hass and Thompson (1989) and Kobayashi and Nishi (1994). |
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Differential Geometry and Geometric Analysis Seminar |
Topic: |
TBA |
Presenter: |
Jie Qing, UC Santa Cruz |
Date: |
Friday, October 29, 2010, Time: 3:00 p.m., Location: Fine Hall 314 |
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Ergodic Theory and Statistical Mechanics Seminar *** Please note special date and time*** |
Topic: |
Diffusive or superdiffusive asymtotics for periodic and non-periodic Lorentz processes |
Presenter: |
Domokos Szasz, Budapest University of Technology and Economics |
Date: |
Friday, October 29, 2010, Time: 3:00 p.m., Location: Fine Hall 401 |
Abstract: |
After the first success in establishing the diffusive, Brownian limit of planar, finite-horizon, periodic Lorentz processes, in 1981 Sinai turned the interest toward studying models when periodicity is hurt, in particular, to locally perturbed Lorentz processes. The 1981 solution for a random-walk-model - by Telcs and the speaker - only led in 2009 to that for the locally perturbed, finite-horizon Lorentz process (by Dolgopyat, Varju and the present author). Beside reporting on these results we also analyze the first steps in extending the limits obtained for the periodic Lorentz process to locally perturbed periodic or quasi-periodic ones (results by Nandori, Paulin, Varju and the speaker). |
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NOVEMBER 2010 |
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Analysis Seminar |
Topic: |
TBA |
Presenter: |
Natasa Pavlovic, University of Texas at Austin |
Date: |
Monday, November 8, 2010, Time: 4:00 p.m., Location: Fine Hall 314 |
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PACM Colloquium |
Topic: |
Novel Phenomena and Models of Active Fluids |
Presenter: |
Michael Shelley, Courant Institute |
Date: |
Monday, November 8, 2010, Time: 4:00 p.m., Location: Fine Hall 214 |
Abstract: |
Fluids with suspended microstructure - complex fluids - are common actors in micro- and biofluidics applications and can have fascinating dynamical behaviors. A new area of complex fluid dynamics concerns "active fluids" which are internally driven by having dynamic microstructure such as swimming bacteria. Such motile suspensions are important to biology, and are candidate systems for tasks such as microfluidic mixing and pumping. To understand these systems, we have developed both first-principles particle and continuum kinetic models for studying the collective dynamics of hydrodynamically interacting microswimmers. The kinetic model couples together the dynamics of a Stokesian fluid with that of an evolving "active" stress field. It has a very interesting analytical and dynamical structure, and predicts critical conditions for the emergence of hydrodynamic instabilities and fluid mixing. These predictions are verified in our detailed particle simulations, and are consistent with current experimental observation. |
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Algebraic Geometry Seminar |
Topic: |
4-dimensional symplectic holomorphic contractions |
Presenter: |
Marco Andreatta, Trento |
Date: |
Tuesday, November 9, 2010, Time: 4:30 p.m., Location: Fine Hall 322 |
Abstract: |
In the talk I will consider birational projective morphisms from smooth holomorphic symplectic fourfolds into affine normal varieties. The ultimate goal will be to classify such maps. For the moment I can present special features of them and discuss some important examples. |
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Mathematical Physics Seminar |
Topic: |
TBA |
Presenter: |
Clément Hongler, Columbia University |
Date: |
Tuesday, November 9, 2010, Time: 4:30 p.m., Location: Jadwin 343 |
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Statistical Mechanics Seminar |
Topic: |
Bethe-Ansatz for the two species totally asymmetric diffusion model |
Presenter: |
Birgit Kauffmann, Purdue University |
Date: |
Wednesday, November 10, 2010, Time: 2:00 p.m., Location: Jadwin Hall 343 |
Abstract: |
We study the two species asymmetric diffusion model that describes two species and vacancies diffusing asymmetrically on a one-dimensional lattice. Our method is the algebraic Bethe Ansatz. We will explain this technique which we use to find the finite-size scaling behavior of the lowest lying eigenstates of the quantum Hamiltonian describing the model. This allows us to extract the dynamical critical exponent. |
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Department Colloquium |
Topic: |
Metaphors in systolic geometry |
Presenter: |
Larry Guth, Toronto University |
Date: |
Wednesday, November 10, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
Abstract: |
The systolic inequality says that any Riemannian metric on an n-dimensional torus with volume 1 contains a non-contractible closed curve with length at most C(n) - a constant depending only on n. One remarkable feature of the inequality is it holds for such a wide class of metrics. It's much more general than an inequality that holds for all metrics obeying a certain curvature condition.
The systolic inequality is a difficult theorem, and each proof is guided by a metaphor that connects the systolic inequality to a different area of geometry or topology. In this talk, I will explain three metaphors. They connect the systolic inequality to minimal surface theory, topological dimension theory, and scalar curvature. |
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Ergodic Theory and Statistical Mechanics Seminar |
Topic: |
TBA |
Presenter: |
Percy Wong, Princeton University |
Date: |
Thursday, November 11, 2010, Time: 2:00 p.m., Location: Fine Hall 401 |
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Discrete Mathematics Seminar |
Topic: |
TBA |
Presenter: |
Oleg Pikhurko, Carnegie Mellon |
Date: |
Thursday, November 11, 2010, Time: 2:15 p.m., Location: Fine Hall 224 |
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Princeton University and IAS Number Theory Seminar |
Topic: |
Periods of special cycles and derivatives of L-series |
Presenter: |
Shou-Wu Zhang, Columbia University |
Date: |
Thursday, November 11, 2010, Time: 4:30 p.m., Location: Fine Hall 214 |
Abstract: |
In this talk, I will state some conjectures and examples concerning the central derivatives of automorphic L-series in terms of heights of special cycles on Shimura varieties. |
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Topology Seminar |
Topic: |
Transverse homology |
Presenter: |
Lenny Ng, Duke University |
Date: |
Thursday, November 11, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
Abstract: |
Knot contact homology is a combinatorial Floer-theoretic knot invariant derived from Symplectic Field Theory. I'll discuss the geometry behind this invariant and a new filtered version, transverse homology, which turns out to be a fairly effective invariant of transverse knots |
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Differential Geometry and Geometric Analysis Seminar |
Topic: |
TBA |
Presenter: |
Olivaine De Queiroz, Universidade Estadual De Campinas |
Date: |
Friday, November 12, 2010, Time: 3:00 p.m., Location: Fine Hall 314 |
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PACM Colloquium |
Topic: |
A New Formalism for Electromagnetic Scattering in Complex Geometry |
Presenter: |
Leslie Greengard, Courant Institute |
Date: |
Monday, November 15, 2010, Time: 4:00 p.m., Location: Fine Hall 214 |
Abstract: |
We will describe some recent, elementary results in the theory of electromagnetic scattering in R3. There are two classical approaches that we will review - one based on the vector and scalar potential and applicable in arbitrary geometry, and one based on two scalar potentials, due to Lorenz, Debye and Mie, valid only in the exterior (or interior) of a sphere. In extending the Lorenz-Debye-Mie approach to arbitrary geometry, we have encountered some new mathematical questions involving differential geometry, partial differential equations and numerical analysis. This is joint work with Charlie Epstein. |
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Algebraic Geometry Seminar |
Topic: |
TBA |
Presenter: |
Tamás Szamuely, Hungarian Academy and University of Pennsylvania |
Date: |
Tuesday, November 16, 2010, Time: 4:30 p.m., Location: Fine Hall 322 |
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Department Colloquium |
Topic: |
Acoustical spacetime geometry and shock formation |
Presenter: |
Demetri Christodoulou, ETH |
Date: |
Wednesday, November 17, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
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Ergodic Theory and Statistical Mechanics Seminar |
Topic: |
TBA |
Presenter: |
Percy Wong, Princeton University |
Date: |
Thursday, November 18, 2010, Time: 2:00 p.m., Location: Fine Hall 401 |
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Discrete Mathematics Seminar |
Topic: |
TBA |
Presenter: |
Noga Alon, Tel-Aviv University and IAS |
Date: |
Thursday, November 18, 2010, Time: 2:15 p.m., Location: Fine Hall 224 |
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Princeton University and IAS Number Theory Seminar |
Topic: |
TBA |
Presenter: |
Tasho Kaletha, Princeton University and IAS |
Date: |
Thursday, November 18, 2010, Time: 4:30 p.m., Location: IAS S-101 |
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Topology Seminar |
Topic: |
TBA |
Presenter: |
Igor Rivin, Temple University |
Date: |
Thursday, November 18, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
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Differential Geometry and Geometric Analysis Seminar |
Topic: |
Laplace eigenvalues via asymptotic separation of variables |
Presenter: |
Chris Judge, Indiana University |
Date: |
Friday, November 19, 2010, Time: 3:00 p.m., Location: Fine Hall 314 |
Abstract: |
We study the behavior of eigenvalues under geometric perturbations using a method that might be called asymptotic separation of variables. In this method, we use quasi-mode approximations to compare the eigenvalues of a warped product and another metric that is asymptotically close to a warped product. As one application, we shoe that the generic Euclidean triangle has simple Laplace spectrum. This is joint work with Luc Hillairet. |
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Analysis Seminar |
Topic: |
TBA |
Presenter: |
Vincent Moncrief, Yale University |
Date: |
Monday, November 22, 2010, Time: 4:00 p.m., Location: Fine Hall 314 |
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PACM Colloquium |
Topic: |
Wavelet Frames and Applications |
Presenter: |
Zuowei Shen, National University of Singapore |
Date: |
Monday, November 22, 2010, Time: 4:00 p.m., Location: Fine Hall 214 |
Abstract: |
This talk focuses on the tight wavelet frames derived from multiresolution analysis and their applications in imaging sciences. One of the major driven forces in the area of applied and computational harmonic analysis over the last two decades is to develop and understand redundant systems that have sparse approximations of different classes of functions. Such redundant systems include wavelet frame, ridgelet, curvelet, shearlet and so on. In this talk, we will first give a brief survey on the development of the unitary extension principle and its generalizations. The unitary extension principle and its extensions give systematical constructions of wavelet frames from multiresolution analysis that can be used in various problems in imaging science. Then we will focus on applications of wavelet frames. Especially, we will discuss frame based image analysis and restorations, which includes image inpainting, image denosing, image deblurring and blind deblurring, image decomposition, and image segmentation. |
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Analysis Seminar |
Topic: |
TBA |
Presenter: |
Colin Guillarmou, Universite de Nice Sophia-Antipolis |
Date: |
Monday, November 29, 2010, Time: 4:00 p.m., Location: Fine Hall 314 |
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DECEMBER 2010 |
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Department Colloquium |
Topic: |
Natural maps old and new |
Presenter: |
Gerard Besson, Grenoble |
Date: |
Wednesday, December 1, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
Abstract: |
In 1995, G. Courtois, S. Gallot and myself constructed a family of maps with very good properties regarding volume elements between certain manifolds. We used it to give an alternative proof of Mostow's rigidity for rank one closed symmetric spaces as well as a rigidity result for their geodesic flow, conjectured by A. Katok. Various modifications of the original construction have been made since yielding new results in different settings. We shall describe the basic construction, the modifications, some applications and open questions. |
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Ergodic Theory and Statistical Mechanics Seminar |
Topic: |
TBA |
Presenter: |
Zhiren Wang
, Princeton University |
Date: |
Thursday, December 2, 2010, Time: 2:00 p.m., Location: Fine Hall 401 |
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Princeton University and IAS Number Theory Seminar |
Topic: |
TBA |
Presenter: |
Christopher Skinner, Princeton University and IAS |
Date: |
Thursday, December 2, 2010, Time: 4:30 p.m., Location: Fine Hall 214 |
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Topology Seminar |
Topic: |
TBA |
Presenter: |
Sa'ar Hersonsky, University of Georgia |
Date: |
Thursday, December 2, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
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Differential Geometry and Geometric Analysis Seminar |
Topic: |
TBA |
Presenter: |
Gilles Courtois, École/ Polytechnique/ |
Date: |
Friday, December 3, 2010, Time: 3:00 p.m., Location: Fine Hall 314 |
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PACM Colloquium |
Topic: |
Diffusions Interacting Through Their Ranks, and the Stability of Large Equity Markets |
Presenter: |
Ioannis Karatzas, Columbia University |
Date: |
Monday, December 6, 2010, Time: 4:00 p.m., Location: Fine Hall 214 |
Abstract: |
We introduce and study ergodic multidimensional diusion processes interacting through their ranks. These interactions give rise to invariant measures which are in broad agreement with stability properties observed in large equity markets over long time-periods. The models we develop assign growth rates and variances that depend on both the name (identity) and the rank (according to capitalization) of each individual asset. Such models are able realistically to capture critical features of the observed stability of capital distribution over the past century, all the while being simple enough to allow for rather detailed analytical study. The methodologies used in this study touch upon the question of triple points for systems of interacting diusions; in particular, some choices of parameters may permit triple (or higher-order) collisions to occur. We show, however, that such multiple collisions have no eect on any of the stability properties of the resulting system. This is accomplished through a detailed analysis of intersection local times. The theory we develop has connections with the analysis of Queueing Networks in heavy traffic, as well as with models of competing particle systems in Statistical Mechanics, such as the Sherrington-Kirkpatrick model for spin-glasses. |
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Princeton University and IAS Number Theory Seminar |
Topic: |
TBA |
Presenter: |
Benedict Gross, Harvard University |
Date: |
Thursday, December 9, 2010, Time: 4:30 p.m., Location: IAS S-101 |
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Algebraic Geometry Seminar |
Topic: |
TBA |
Presenter: |
Izzet Coskun, UIC |
Date: |
Tuesday, December 14, 2010, Time: 4:30 p.m., Location: Fine Hall 322 |
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Joint Princeton University and IAS Number Theory Seminar |
Topic: |
TBA |
Presenter: |
Henryk Iwaniec, Rutgers University |
Date: |
Thursday, December 16, 2010, Time: 4:30 p.m., Location: Fine Hall 214 |
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Topology Seminar |
Topic: |
TBA |
Presenter: |
Andy Cotton-Clay, Harvard University |
Date: |
Thursday, December 16, 2010, Time: 4:30 p.m., Location: Fine Hall 314 |
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