# Upcoming Seminars & Events

## Primary tabs

April 17, 2014
2:00pm - 3:30pm
##### Effective Ratner Theorem for ASL(2,R) and gaps in n^(1/2) modulo 1
###### Ergodic Theory & Statistical Mechanics

Let G=SL(2, R) \ltimes R^2 and \Gamma= SL(2, Z) ltimes Z^2. We prove a rate of equidistribution for the orbits of a certain 1-dimensional unipotent flow of \Gamma \quot G, which projects to a closed horocycle in the unit tangent bundle to the modular surface.

Speaker: Ilya Vinogradov , University of Bristol
Location:
Fine Hall 601
April 17, 2014
3:00pm - 4:00pm
##### Slices of co-operations for KGL
###### Algebraic Topology Seminar

The classic structure of the co-operations KU(KU) of topological K-theory as a Hopf algeboid is due to Adams.  In joint work with Pelaez, we determine the analogous structure for algebraic K-theory KGL, regarded as a motivic spectrum.  Applying the motivic slice filtration, we solve a problem of Voevodsky.

Speaker: Chuck Weibel, IAS
Location:
Fine Hall 214
April 17, 2014
4:30pm - 5:30pm
##### Non-simple genus minimizers in lens spaces
###### Topology Seminar

When does a knot in a 3-manifold have the smallest genus amongst all knots homologous to it? This is a basic but largely unexplored problem, and addressing it for lens spaces is closely connected with the Berge conjecture, which posits when surgery along a knot in the three-sphere can produce a lens space.

Speaker: Josh Greene, Boston College
Location:
Fine Hall 314
April 17, 2014
4:30pm - 5:30pm
##### Unique Ergodicity and Mixing for the Degenerately forced Boussinesq Equations and related systems
###### Analysis of Fluids and Related Topics

We establish the existence, uniqueness and attraction properties of an ergodic invariant measure for the Boussinesq Equations in the presence of a degenerate stochastic forcing acting only in the temperature equation and only at the largest spatial scales. The central challenge is to establish time asymptotic smoothing properties of the Markovian dynamics corresponding to this system.

Speaker: Nathan Glatt-Holtz , Virginia Tech
Location:
Fine Hall 322
April 17, 2014
4:30pm - 5:30pm
##### Epipelagic representations and rigid local systems
###### Princeton University/IAS Number Theory Seminar

Reeder and Yu have constructed in a uniform way certain supercuspidal representations of p-adic groups called "epipelagic representations", using invariant theory studied by Vinberg et al.

Speaker: Zhiwei Yun , Stanford University
Location:
Fine Hall 214
April 18, 2014
3:00pm - 4:00pm
##### Berger decomposition, Weitzenbock formula and canonical metrics on four-manifolds
###### Differential Geometry & Geometric Analysis Seminar

In this talk we will first provide an alternative proof of the Weitzenbock formula using Berger curvature decomposition, as applications we will discuss rigidity of Einstein four-manifolds under some positive curvature
conditions. At the end we will discuss the Weitzenbock formula for generalized quasi-Einstein metrics on four-manifolds.

Speaker: Peng Wu , Cornell University
Location:
Fine Hall 314
April 18, 2014
4:15pm - 5:15pm
##### Bounds on the Bondi mass in perturbations of the Schwarzschild exteriors
###### Differential Geometry & Geometric Analysis Seminar

Please note special time (4:15).   We consider vacuum perturbations of the Schwarzschild black hole exteriors and derive bounds on the Bondi mass and energy at past null infinity in terms of the area of certain carefully chosen sections of the apparent horizon.  The method relies on a perturbation argument; in particular it only requires a slab of space-time around a smooth nul

Speaker: Spyros Alexakis, University of Toronto
Location:
Fine Hall 314
April 18, 2014
4:30pm - 5:30pm
##### TBA - Okounkov
###### Minerva Distinguished Visitor Lectures
Speaker: Andrei Okounkov, Columbia University
Location:
Fine Hall 214
April 21, 2014
3:15pm - 4:15pm
##### Recent progress on the Landis conjecture
###### Analysis Seminar

PLEASE CLICK ON SEMINAR TITLE FOR COMPLETE ABSTRACT. In the late 60's, E.M. Landis conjectured that if $\Delta u+Vu=0$ in $\mathbb{R}^n$ with $\|V\|_{L^{\infty}(\mathbb{R}^n)}\le 1$ and $\|u\|_{L^{\infty}(\mathbb{R}^n)}\le C_0$ satisfying $|u(x)|\le C\exp(-C|x|^{1+})$, then $u\equiv 0$.

Speaker: Jeen-Nan Wang , National Taiwan University
Location:
Fine Hall 314
April 21, 2014
3:30pm - 4:30pm
##### A transition formula for mean values of Dirichlet polynomials
###### Princeton University/IAS Number Theory Seminar

Please note special day (Monday) and location.

Speaker: Tom Zhang , IAS and University of New Hampshire
Location:
IAS Room S-101
April 21, 2014
4:30pm - 5:30pm
##### Curvature suppresses the Rayleigh-Taylor instability
###### PACM/Applied Mathematics Colloquium

PLEASE CLICK ON COLLOQUIUM TITLE FOR EACH COMPLETE ABSTRACT. Naima Hammoud's abstract: Thin films on curved surfaces are widely observed in coating and painting processes and wetting problems.
Haoshu Tian's abstract: The default of one bank can cause other banks to default through two channels: financial contagion in the inter-bank liability network and fire sale in the asset selling market. When the defaulted bank cannot fully pay its debt, the loss is transmitted to other banks.

Speaker: Naima Hammoud & Haoshu Tian - PACM Graduate Students, Princeton University
Location:
Fine Hall 214
April 22, 2014
4:30pm - 5:30pm
##### Birational geometry of moduli of stable rational curves
###### Algebraic Geometry Seminar

I will report on joint work with Castravet on birational geometry of moduli of stable rational curves with n punctures. In particular, we show that it is not a Mori Dream Space when n is at least 134, answering a question of Hu and Keel.

Speaker: Jenia Tevelev , University of Massachusetts
Location:
Fine Hall 322
April 23, 2014
4:30pm - 6:00pm
##### TBA - Li
###### Department Colloquium
Speaker: Winnie Li , Penn State University
Location:
Fine Hall 314
April 24, 2014
2:00pm - 3:30pm
##### TBA - Avdeeva
###### Ergodic Theory & Statistical Mechanics
Speaker: Maria Avdeeva , Princeton University
Location:
Fine Hall 601
April 24, 2014
3:00pm - 4:00pm
##### TBA - Bendersky
###### Algebraic Topology Seminar
Speaker: Martin Bendersky, City University of New York (CUNY)
Location:
Fine Hall 214
April 24, 2014
4:30pm - 6:00pm
##### TBA - Filmus
###### Discrete Mathematics Seminar
Speaker: Yuval Filmus , IAS
Location:
Fine Hall 224
April 24, 2014
4:30pm - 5:30pm
##### TBA - Culler
###### Topology Seminar
Speaker: Lucas Culler, MIT
Location:
Fine Hall 314
April 24, 2014
4:30pm - 5:30pm
##### TBA - Boxer
###### Princeton University/IAS Number Theory Seminar
Speaker: George Boxer , Harvard University
Location:
IAS Room S-101
April 24, 2014
4:30pm - 5:30pm
##### On active scalar equations with nonlocal velocity.
###### Analysis of Fluids and Related Topics

The problem of finite-time singularity versus global regularity for active scalar equations with nonlocal velocities has attracted much attention in recent years. In this talk, I will discuss some recent results in this direction.

Speaker: Hongjie Dong , Brown University
Location:
Fine Hall 322
April 25, 2014
3:00pm - 4:00pm
##### Structure of measures in Lipschitz differentiability spaces
###### Differential Geometry & Geometric Analysis Seminar

This talk will present results showing the equivalence of two very different ways of generalising Rademacher's theorem to metric measure spaces. The first was introduced by Cheeger and is based upon

Speaker: David Bate , University of Chicago
Location:
Fine Hall 314