# Seminars & Events for 2015-2016

May 5, 2016
4:30pm - 5:30pm
##### Rational curves on elliptic surfaces
###### Princeton University/IAS Number Theory Seminar

Given a non-isotrivial elliptic curve E over K=Fq(t), there is always a finite extension L of K which is itself a rational function field such that E(L) has large rank.

Speaker: Douglas Ulmer, Georgia Institute of Technology
Location:
IAS Room S-101
May 5, 2016
4:30pm - 5:30pm
###### Topology Seminar

We shall discuss long time existence and convergence properties of Yang-Mills gradient flow over closed, four-dimensional manifolds and applications to Morse theory for the quotient space of connections modulo gauge transformations.

Speaker: Paul Feehan , Rutgers/IAS
Location:
Fine Hall 314
May 6, 2016
3:00pm - 4:00pm
##### Volumes of minimal hypersurfaces and stationary geodesic nets
###### Differential Geometry & Geometric Analysis Seminar

We will prove an upper bound for the volume of a minimal hypersurface in a closed Riemannian manifold conformally equivalent to a manifold with Ric > -(n-1). In the second part of the talk we will construct a sweepout of a closed 3-manifold with positive Ricci curvature by 1-cycles of controlled length and prove an upper bound for the length of a stationary geodesic net.

Speaker: Yevgeny Liokumovich , Imperial College London
Location:
Fine Hall 314
May 7, 2016
9:00am - 6:00pm
##### Tokyo-Princeton algebraic geometry conference
###### Special Events and Conferences
Speaker: Various,
Location:
Fine Hall 314
May 8, 2016
9:00am - 6:00pm
##### Tokyo-Princeton algebraic geometry conference
###### Special Events and Conferences
Speaker: Various,
Location:
Fine Hall 314
May 9, 2016
9:00am - 6:00pm
##### Tokyo-Princeton algebraic geometry conference
###### Special Events and Conferences
Speaker: Various,
Location:
Fine Hall 314
May 9, 2016
2:30pm - 3:30pm
##### Optimal detection of weak principal components in high-dimensional data
###### PACM IDeAS

Please note special day (Monday).   Principal component analysis is a widely used method for dimension reduction. In high dimensional data, the signal'' eigenvalues corresponding to weak principal components (PCs) do not necessarily separate from the bulk of the noise'' eigenvalues.

Speaker: Edgar Dobriban, Stanford University
Location:
TBD
May 9, 2016
3:15pm - 4:30pm
##### Stability and instability results for scalar waves on general asymptotically flat spacetimes
###### Analysis Seminar

In the first part of this talk, we will prove a logarithmic decay result for solutions to the scalar wave equation $\square_{g}\psi=0$ on general asymptotically flat spacetimes $(\mathcal{M},g)$, possibly bounded by an event horizon with positive surface gravity and having a small ergosphere, provided a uniform energy boundedness estimate holds on $(\mathcal{M},g)$.

Speaker: Georgios Moschidis , Princeton University
Location:
Fine Hall 110
May 10, 2016
9:00am - 2:00pm
Speaker: ,
Location:
Fine Hall 314
May 10, 2016
2:00pm - 3:30pm
##### Quantum ergodicity and Benjamini-Schramm convergence of hyperbolic surfaces
###### Ergodic Theory & Statistical Mechanics

Please note special day (Tuesday).   Quantum Ergodicity Theorem of Shnirelman, Zelditch and Colin de Verdière is an equidistribution result of eigenfunctions of the Laplacian in large frequency limit on a Riemannian manifold with an ergodic geodesic flow.

Speaker: Tuomas Sahlsten, Univeristy of Bristol
Location:
Fine Hall 601
May 10, 2016
4:30pm - 5:30pm
##### On the Hilbert Property and the fundamental group of algebraic varieties
###### Princeton University/IAS Number Theory Seminar

Please note special day (Tuesday).    This concerns recent work with P. Corvaja in which we relate the Hilbert Property for an algebraic variety (a kind of axiom linked with Hilbert Irreducibility, relevant e.g. for the Inverse Galois Problem) with the fundamental group of the variety. In particular, this leads to new examples (of surfaces) of failure of the Hilbert Property.

Speaker: Umberto Zannier , SNS Pisa
Location:
Fine Hall 214
May 11, 2016
2:30pm - 3:30pm
##### On the Solution of Elliptic Partial Differential Equations on Regions with Corners
###### PACM IDeAS

The solution of elliptic partial differential equations on regions with non-smooth boundaries (edges, corners, etc.) is a notoriously refractory problem.

Speaker: Kirill Serkh, Yale University
Location:
Fine Hall 224
May 12, 2016
2:00pm - 3:30pm
##### Ratner's theorems and applications
###### Ergodic Theory & Statistical Mechanics

In the early 1980s, Marina Ratner published three papers about horocycle flows on the unit tangent bundle of a surface of constant negative curvature with finite volume. In the early 1990s, by expanding the ideas from her study of horocycle flows, Ratner proved a series of beautiful results about unipotent flows on homogeneous spaces.

Speaker: Wen-Liang Tseng , National Taiwan University
Location:
Fine Hall 601
May 16, 2016
9:00am - 5:00pm
##### Women and Math - Princeton Day
###### Special Events and Conferences
 10:30—11:30 AM: Speaker:   Zoltán Szabó, Professor of Mathematics, Princeton University Title:           “Floer homology invariants for knots.”
Speaker: Various,
Location:
Fine Hall 314
May 18, 2016
2:30pm - 3:30pm
##### Randomized Algorithms for Matrix Decomposition
###### PACM IDeAS

Matrix decompositions, and especially SVD, are very important tools in data analysis. When big data is processed, the computation of matrix decompositions becomes expensive and impractical. In recent years, several algorithms, which approximate matrix decomposition, have been developed. These algorithms are based on metric conservation features for linear spaces of random projections.

Speaker: Yariv Aizenbud, Tel Aviv University
Location:
Fine Hall 224
May 19, 2016
4:30pm - 5:30pm
##### On p-torsion in class groups of number fields
###### Princeton University/IAS Number Theory Seminar

Gauss famously investigated class numbers of quadratic fields, in particular characterizing the 2-divisibility of the class number for such fields. In general, it is expected that for a number field of any degree, and any rational prime p, the p-torsion part of the class group  should be arbitrarily small, in a suitable sense, relative to the absolute discriminant of the field.

Speaker: Lillian Pierce, Duke University
Location:
Fine Hall 214
May 19, 2016
4:30pm - 5:30pm
##### The Dirichlet problem for the constant mean curvature equation in Sol$_3$
###### Differential Geometry & Geometric Analysis Seminar

Please note different day (Thursday).   The Dirichlet problem for CMC surfaces with infinite boundary data was first studied for minimal graphs in $\mathbb{R}^3$ by Jenkins and Serrin and then by Sprück for CMC $H$ surfaces.

Speaker: Patricia Klaser , UFRGS-Brazil
Location:
Fine Hall 314
May 20, 2016
3:00pm - 4:00pm
##### Uniqueness of immersed spheres in three-manifolds. Proof of a conjecture by Alexandrov
###### Differential Geometry & Geometric Analysis Seminar

In this talk we generalize Hopf's famous classification of constant mean curvature spheres in R^3 to the general situation of classes of surfaces modeled by arbitrary elliptic PDEs in arbitrary three-manifolds, with the only hypothesis of the existence of a family of "candidate surfaces". In this way, we prove that any immersed sphere in such a class of surfaces is a candidate sphere.

Speaker: Pablo Mira , Universidad Politécnica de Cartagena
Location:
Fine Hall 314
May 20, 2016
4:15pm - 5:15pm
##### Min-max theory in Gaussian space and Entropy Conjecture
###### Differential Geometry & Geometric Analysis Seminar

Please note additional talk and special time (4:15).   Minimal surfaces are critical points of the area functional. The min-max theory is a variational theory for constructing saddle point type, unstable minimal surfaces. In this talk, we will introduce a min-max theory in a specific space--the Gaussian probability space.

Speaker: Xin Zhou , MIT
Location:
Fine Hall 314
May 26, 2016
4:30pm - 5:30pm
##### Divisibility of coefficients of modular forms
###### Princeton University/IAS Number Theory Seminar

I will explain two recent results concerning non-zero coefficients of modular forms modulo a prime p. The first result, a joint work with K. Soundararajan, gives an asymptotic equivalent for the number of such coefficients. The second is concerned with the set of primes which are indices of non-zero coefficients.

Speaker: Joel Bellaiche , Brandeis University
Location:
Fine Hall 214