# Upcoming Seminars & Events

## Primary tabs

November 24, 2014
3:15pm - 4:30pm
##### TBA - Hintz
###### Analysis Seminar
Speaker: Peter Hintz , Stanford University
Location:
Fine Hall 314
November 24, 2014
4:30pm - 5:30pm
##### Eigenvector Centralities for Temporal Networks
###### PACM/Applied Mathematics Colloquium

Motivated by a series of examples (the U.S. Ph.D. exchange in mathematics, co-starring relationships among top-billed actors in Hollywood, and co-citations between U.S. Supreme Court decisions), we study the general problem of calculating eigenvector centralities as generalized to temporal directed network data. We investigate a parsimonious extension of hub and authority scores to "multilayer" situations where multiple slices of network data connect similar groups of agents in different settings. By varying the coupling between layers, we develop a family of centrality measures whose values are localized in time in one extreme (weakly coupled) and constant across time in the other (strongly coupled). By deriving the first terms of the singular perturbation expansion in the strongly-coupled singular limit of this framework, we derive expressions for principled specification of the time-averaged centrality and the biggest centrality movers over the time period.   This work is in collaboration with Sean Myers, Dane Taylor, Elizabeth Leicht, Aaron Clauset and Mason Porter.

Speaker: Peter Mucha , University of North Carolina
Location:
Fine Hall 214
November 25, 2014
4:00pm - 5:30pm
##### Interface dynamics for incompressible flows
###### Minerva Distinguished Visitor Lectures

The goal of these lectures is to present the main ideas and arguments of recent results concerning global solutions and finite time singularities for interface dynamics. In particular those contour dynamics that are given by basic fluid mechanics systems; Euler´s equation, Darcy´s law and the Quasi-geostrophic equation. These give rise to problems such as water wave, Muskat, and the evolution of sharp fronts of temperature.

Speaker: Diego Cordoba Gazolaz, Princeton University
Location:
Fine Hall 110
December 1, 2014
4:30pm - 5:30pm
##### When Exactly Do Quantum Computers Provide a Speedup?
###### PACM/Applied Mathematics Colloquium

Twenty years after the discovery of Shor's factoring algorithm, I'll survey what we now understand about the structure of problems that admit quantum speedups.  I'll start with the basics, discussing the hidden subgroup, amplitude amplification, adiabatic, and linear systems paradigms for quantum algorithms.  Then I'll move on to some general results, obtained by Andris Ambainis and myself over the last few years, about quantum speedups in the black-box model.  These results include the impossibility of a superpolynomial quantum speedup for any problem with permutation symmetry, and the largest possible separation between classical and quantum query complexities for any problem.

Speaker: Scott Aaronson , MIT
Location:
Fine Hall 214
December 2, 2014
2:00pm - 3:00pm
##### TBA - Nori
###### Algebraic Geometry Seminar
Speaker: Mahdav Nori , University of Chicago
Location:
IAS Room S-101
December 2, 2014
4:00pm - 5:30pm
##### Interface dynamics for incompressible flows
###### Minerva Distinguished Visitor Lectures

The goal of these lectures is to present the main ideas and arguments of recent results concerning global solutions and finite time singularities for interface dynamics. In particular those contour dynamics that are given by basic fluid mechanics systems; Euler´s equation, Darcy´s law and the Quasi-geostrophic equation. These give rise to problems such as water wave, Muskat, and the evolution of sharp fronts of temperature.

Speaker: Diego Cordoba Gazolaz, Princeton University
Location:
Fine Hall 110
December 3, 2014
11:00am - 12:30pm
##### TBA - McLean
###### Algebraic Geometry Seminar

Speaker: Mark McLean , Stony Brook University
Location:
IAS Room S-101
December 4, 2014
2:00pm - 3:30pm
###### Ergodic Theory & Statistical Mechanics
Speaker: Benoit Pausader , Princeton University
Location:
Fine Hall 601
December 4, 2014
3:00pm - 4:00pm
##### On the number of rich lines in truly high dimensional sets
###### Discrete Mathematics Seminar

We prove a new upper bound on the number of r-rich lines (lines with at least r points) in a truly' d-dimensional configuration of points v_1,...,v_n over the complex numbers. More formally, we show that, if the number of r-rich lines is significantly larger than n^2/r^d then there must exist a large subset of the points  contained in a hyperplane. We conjecture that the factor r^d can be replaced with a tight r^{d+1}. If true,  this would generalize the classic Szemeredi-Trotter theorem  which gives a bound of n^2/r^3 on the number of r-rich lines in a planar configuration. This conjecture was shown to hold in R^3 in a seminal work of Guth and Katz (2010) and was recently proved  over R^4 (under some additional restrictions) by Solomon and Sharir.  Although our bound is not optimal, it is the first to hold in arbitrary dimension. For the special case of arithmetic progressions (r collinear points that are evenly distanced) we give a bound that is tight up to low order terms, showing that a d-dimensional grid achieves the largest number of r-term progressions. Joint work with Sivakanth Gopi (Princeton).

Speaker: Zeev Dvir, Princeton University
Location:
Fine Hall 224
December 4, 2014
3:00pm - 4:00pm
##### TBA - Patel
###### Algebraic Topology Seminar
Speaker: Amit Patel, IAS
Location:
Fine Hall 314
December 4, 2014
4:30pm - 5:30pm
##### Mean Curvature Flow of Cones
###### Joint Princeton Rutgers Geometric PDEs Seminar

For smooth initial hypersurfaces one has short time existence and uniqueness of solutions to Mean Curvature Flow.  For general initial data Brakke showed that varifold solutions exist, but that they need not be unique if the initial data are non smooth.  In this talk I will discuss the multitude of solutions to MCF that exist if the initial hypersurface is a cone that is smooth except at the origin.  Some of the examples go back to older work with Chopp, Ilmanen, and Velazquez, other examples are recent.

Speaker: Sigurd Angenent, University of Wisconsin, Madison
Location:
Fine Hall 214
December 4, 2014
4:30pm - 5:30pm
##### Level raising mod 2 and arbitrary 2-Selmer ranks
###### Princeton University/IAS Number Theory Seminar

We prove a level raising mod p=2 theorem for elliptic curves over Q, generalizing theorems of Ribet and Diamond-Taylor. As an application, we show that the 2-Selmer rank can be arbitrary in level raising families. We will begin by explaining our motivation from W. Zhang's approach to the p-part of the BSD conjecture. Explicit examples will be given to illustrate different phenomena compared to odd p. This is joint work with Bao V. Le Hung.

Speaker: Chao Li , Harvard University
Location:
IAS Room S-101
December 4, 2014
4:30pm - 6:00pm
##### Interface Singularities for the Euler Equations
###### Analysis of Fluids and Related Topics

The fluid interface  `splash'' singularity was introduced by Castro, C\'{o}rdoba,  Fefferman, Gancedo, \& G\'{o}mez-Serrano.  A splash singularity occurs when a fluid interface remains locally smooth but self-intersects in finite time.   In this talk, I will very briefly discuss how we construct splash singularities for the one-phase 3-D Euler and Navier-Stokes equations.  I will then discuss the problem of two-phase Euler flow.   Recently, Fefferman, Ionescu, and Lie have shown that a locally smooth vortex sheet cannot self-intersect in finite time.   I will explain our proof of this result, which is based on elementary arguments and some precise blow-up rates for the gradient of the velocity of the fluid through which the interfaces tries to self-intersect.   This is joint work with D. Coutand.

Speaker: Steve Shkoller , UC Davis
Location:
Fine Hall 322
December 4, 2014
4:30pm - 5:30pm
##### Heegaard Floer homologies and cuspidal curves
###### Topology Seminar
Speaker: Maciej Borodzik, University of Warsaw
Location:
Fine Hall 314
December 4, 2014
5:45pm - 6:45pm
##### Geometry of the space of probability measures
###### Joint Princeton Rutgers Geometric PDEs Seminar

The space of probability measures, on a compact Riemannian manifold, carries the Wasserstein metric coming from optimal transport. Otto found a remarkable formal Riemannian metric on this infinite-dimensional space. It is a challenge to make rigorous sense of the ensuing formal calculations, within the framework of metric geometry. I will describe what is known about geodesics, curvature, tangent spaces (cones) and parallel transport.

Speaker: John Lott, University of California, Berkeley
Location:
Fine Hall 214
December 5, 2014
1:30pm - 2:30pm
##### TBA - Xu
###### Symplectic Geometry Seminar
Speaker: Guangbo Xu , UCI
Location:
Fine Hall 322
December 5, 2014
2:00pm - 3:00pm
##### TBA - Saint-Raymond
###### Analysis Seminar

This is a joint Analysis - Analysis of Fluids and Related Topics seminar.

Speaker: Laure Saint-Raymond , ENS, France
Location:
Fine Hall 214
December 5, 2014
2:00pm - 3:00pm
##### TBA - Saint-Raymond
###### Analysis of Fluids and Related Topics

This is a joint Analysis of Fluids and Related Topics - Analysis seminar.

Speaker: Laure Saint-Raymond , ENS, France
Location:
Fine Hall 214
December 5, 2014
3:00pm - 4:00pm
##### TBA - Streets
###### Differential Geometry & Geometric Analysis Seminar
Speaker: Jeff Streets, University of California Irvine
Location:
Fine Hall 314
December 5, 2014
4:00pm - 5:30pm
##### Interface dynamics for incompressible flows
###### Minerva Distinguished Visitor Lectures

The goal of these lectures is to present the main ideas and arguments of recent results concerning global solutions and finite time singularities for interface dynamics. In particular those contour dynamics that are given by basic fluid mechanics systems; Euler´s equation, Darcy´s law and the Quasi-geostrophic equation. These give rise to problems such as water wave, Muskat, and the evolution of sharp fronts of temperature.

Speaker: Diego Cordoba Gazolaz, Princeton University
Location:
Fine Hall 110