Current Seminars
updated 11/26/ 2002

Week of  November 26 - November 29, 2002
Algebraic Geometry Seminar
Topic: The Nash conjecture on arc families of singularities
Presenter: János Kollár, Princeton University
Date: Tuesday, November 26, 2002, Time: 4:30 p.m., Location: Fine Hall 322
Week of December 2 - December 6, 2002
Analysis Seminar
Topic: TBA
Presenter:  Mihaela Iftime,  Northeastern University
Date:  Monday, December 2, 2002, Time: 4:00 p.m., Location: Fine Hall 314
PACM Colloquium
Topic: Nonlinear Scroedinger equations as models of superfluidity
Presenter:  Natalia Berloff, University of Cambridge
Date:  Monday, December 2, 2002, Time: 4:00 p.m., Location: Fine Hall 214
Abstract: Quantum effects dominate the behaviour of liquid helium and other Bose-Einstein condensed fluids. These effects, which include the existence of discrete quantized vortices and the quantization of hydrodynamic circulation, place severe restrictions on the types of flow that can take place in the superfluid phase. Turbulent flows in such systems are also of great interest, not only in their own right, but also because they often appear to share important characteristics with those found in classical fluids.  The Gross-Pitaevskii (GP) equation, also known in nonlinear optics as the defocusing nonlinear Schroedinger equation, is used to elucidate different aspects of superfluid behaviour: the motion, interactions, annihilations, nucleation and reconnections of vortex lines, vortex rings, and vortex loops; the motion of impurities and their capture by vortex lines. New variations of the GP equation that are more faithful to real helium II are also considered.
Arnold's Diffusion Seminar
Topic: TBA
Presenter:  K. Khanin,  Cambridge University
Date:  Tuesday, December 3, 2002, Time: 4:00 p.m., Location: Fine Hall 401
Algebraic Geometry Seminar
Topic: Galois groups of function fields
Presenter: Yuri Tschinkel, Princeton University
Date: Tuesday, December 3, 2002, Time: 4:30 p.m., Location: Fine Hall 322
Statististical Mechanics Seminar
Topic: Phase separation in the Falicov-Kimball Model
Presenter: Pedro Goldbaum,   Princeton University
Date Wednesday, December 4, 2002, Time: 2:00 p.m., Location: Jadwin 343
Abstract: The proof of phase separation of the two kinds of fermions in the Falicov-Kimball model will be discussed. This segregated phase away from half-filling results from strong fermion correlations and is in contrast to the crystalline phase which displays long range order at half-filling. Recent calculations of a new coefficient for the segregation energy will also be discussed.
Department Colloquium
Topic: $H^{1/2}$ with values into $S^1$ and the Ginzburg-Landau model in 3-d
Presenter:  Haim Brezis,  Rutgers University and Paris VI
Date:  Wednesday, December 4, 2002, Time: 4:30 p.m., Location: Fine Hall 314
Abstract: Please click here to view abstract
Discrete Mathematics Seminar
Topic: TBA
Presenter:  Peter Winkler, Bell Labs
Date:  Thursday, December 5, 2002, Time: 2:15  p.m., Location: Fine Hall 224
Joint Princeton University/IAS Number Theory Seminar
Topic: Shioda-Inose structures of one parameter families of K3 surfaces
Presenter:  Ling Long,  IAS
Date:  Thursday, December 5,  2002:  Time:  4:30, Location:  Fine Hall 322
Abstract: Based on a special structure for certain  K3 surfaces with large Picard number, the Shioda-Inose structure, we develop an algorithm to solve some arithmetic problems. For example, given a one parameter family of algebraic elliptic  K3 surfaces with generic Picard number 19,  we can use this algorithm to identify fibers whose groups of global sections (with respect to a fixed fibration) having larger rank. As a further result, we can obtain some identities involving character sums.
Topology Seminar *** Please note change in time
Topic: Ending laminations and the classification of hyperbolic 3-manifolds
Presenter:  Yair Minsky, SUNY at Stonybrook
Date:  Thursday, December 5, 2002:  Time:  4:30 p.m., Location:  Fine Hall 314
Geometric Analysis  Seminar
Topic: TBA
Presenter:  Andrea Malchiodi, IAS
Date:  Friday, December 6, 2002, Time: 3:00 p.m., Location: Fine Hall 314
Week of December 9 - December 13, 2002
Analysis Seminar
Topic: TBA
Presenter:  Vincent Moncrief,  Yale University
Date:  Monday, December 9, 2002, Time: 4:00 p.m., Location: Fine Hall 314
Algebraic Geometry Seminar
Topic: Jets, arcs and minimal log discrepancies
Presenter:  Mircea Mustata, Clay and Harvard University
Date:  Tuesday, December 10, 2002, Time: 4:30 p.m., Location: Fine Hall 322
Department Colloquium
Topic: Gauge Symmetry Breaking
Presenter:  Ed Witten,  Institute for Advanced Study
Date:  Wednesday, December 11, 2002, Time: 4:30 p.m., Location: Fine Hall 314
Abstract: I will describe the gauge symmetry breaking that is observed in superconductors and has an analog in four-manifold theory, and the gauge symmetry breaking in elementary particle physics that physicists are still aiming to understand more fully.
Discrete Mathematics Seminar
Topic: A generalisation of a conjecture of Erdos and Rothschild
Presenter:  Peter Keevash, Princeton University
Date:  Thursday, December 12, 2002, Time: 2:15  p.m., Location: Fine Hall 224
Abstract: Please click here to view abstract
Joint Princeton University/IAS Number Theory Seminar
Topic: Automorphic representations of a symplectic group
Presenter:  Yuval Flicker,  Ohio State University
Date:  Thursday, December 12,  2002:  Time:  4:30, Location:  Fine Hall 322
Abstract: I would like to describe the admissible and automorphic representations of PGSp(2) in terms of liftings related to PGL(4), PGL(2)xPGL(2), SO(4), stated using character relations. This permits a definition of packets, proof of multiplicity one, listing all counter-examples to Ramanujan's conjecture, and potential applications toShimura varieties.
Topology Seminar *** Please note change in time
Topic: Negative curvature and exotic smooth surfaces
Presenter:  Tom Farrell, State University of New York at Binghamton
Date:  Thursday, December 12, 2002:  Time:  4:30p.m., Location:  Fine Hall 314