Previous Conferences & Workshops

May
05
2020

Computer Science/Discrete Mathematics Seminar II

Recent Progress on Cutting Planes Proofs
Noah Fleming
10:30am|https://theias.zoom.us/j/360043913

 

Proof Complexity studies the length of proofs of propositional tautologies in various restricted proof systems. One of the most well-studied is the Cutting Planes proof system, which captures reasoning which can be expressed using linear...

May
04
2020

Analysis Seminar

Exponential mixing of 3D Anosov flows
11:00am|https://theias.zoom.us/j/562592856

We show that a topologically mixing C^\infty Anosov flow on a 3 dimensional compact manifold is exponential mixing with respect to any equilibrium measure with Holder potential. This is a joint work with Masato Tsujii.

May
04
2020

Computer Science/Discrete Mathematics Seminar I

Local Statistics, Semidefinite Programming, and Community Detection
Prasad Raghavendra
11:00am|https://theias.zoom.us/j/360043913

We propose a new hierarchy of semidefinite programming relaxations for inference problems. As test cases, we consider the problem of community detection in block models. The vertices are partitioned into k communities, and a graph is sampled...

May
01
2020

Joint IAS/Princeton/Montreal/Paris/Tel-Aviv Symplectic Geometry Zoominar

Zoll contact forms are local maximisers of the systolic ratio
Alberto Abbondandolo
9:00am|https://princeton.zoom.us/j/745635914

 

A central question from systolic geometry is to find upper bounds for the systolic ratio of a Riemannian metric on a closed $n$-dimensional manifold, i.e. the ratio of the $n$-th power of the shortest length of closed geodesics by the volume...

Apr
30
2020

Joint IAS/Princeton University Number Theory Seminar

Eulerianity of Fourier coefficients of automorphic forms
Henrik Gustafsson
4:30pm|https://theias.zoom.us/j/959183254

The factorization of Fourier coefficients of automorphic forms plays an important role in a wide range of topics, from the study of L-functions to the interpretation of scattering amplitudes in string theory. In this talk I will present a transfer...

Apr
30
2020

Theoretical Machine Learning Seminar

Latent Stochastic Differential Equations for Irregularly-Sampled Time Series
David Duvenaud
3:00pm|Remote Access Only - see link below

Much real-world data is sampled at irregular intervals, but most time series models require regularly-sampled data. Continuous-time models address this problem, but until now only deterministic (ODE) models or linear-Gaussian models were efficiently...

Apr
29
2020

Mathematical Conversations

Musings about a 10-year collaboration with biological morphologists, or how to make biologists comfortable with fiber bundles.
5:30pm|Remote Access Only

In the course of this collaboration, both sides learned about the other field; to my surprise, the biologists learned to "speak" some mathematics. Also, when they saw how we approached answering their initial questions, the questions changed. And...

Apr
28
2020

Analysis Seminar

Ellipses of small eccentricity are determined by their Dirichlet (or, Neumann) spectra
Steven Morris Zelditch
11:00am|https://theias.zoom.us/j/562592856

In 1965, M. Kac proved that discs were uniquely determined by their Dirichlet (or, Neumann) spectra. Until recently, disks were the only smooth plane domains known to be determined by their eigenvalues. Recently, H. Hezari and I proved that ellipses...

Apr
28
2020

Computer Science/Discrete Mathematics Seminar II

A Framework for Quadratic Form Maximization over Convex Sets
10:30am|https://theias.zoom.us/j/360043913

We investigate the approximability of the following optimization problem, whose input is an
n-by-n matrix A and an origin symmetric convex set C that is given by a membership oracle:
"Maximize the quadratic form as x ranges over C."

This is a rich...

Apr
27
2020

Computer Science/Discrete Mathematics Seminar I

Graph and Hypergraph Sparsification
Luca Trevisan and Kobbi Nissim
11:00am|https://theias.zoom.us/j/360043913

 

A weighted graph H is a sparsifier of a graph G if H has much fewer edges than G and, in an appropriate technical sense, H "approximates" G. Sparsifiers are useful as compressed representations of graphs and to speed up certain graph algorithms...