Previous Conferences & Workshops

Oct
28
2020

Mathematical Conversations

Wild low-rank maps
5:30pm|Remote Access

In 1979, Kaufman constructed a remarkable surjective Lipschitz map from a cube to a square whose derivative has rank $1$ almost everywhere. In this talk, we will present some higher-dimensional generalizations of Kaufman's construction that lead to...

Oct
28
2020

Geometric and Modular Representation Theory Seminar

Derived Equivariant Cohomology of the affine Grassmannian and Bezrukavnikov and Finkelberg’s equivalences
3:00pm|Simonyi Hall 101 and Remote Access

This is the third talk in a series of three talks on the derived Satake equivalence. I will give an overview of the article of Bezrukavnikov and Finkelberg which explains how the equivariant derived category of the affine Grassmannian can be...

Oct
28
2020

Stability and Testability

Stability, testability and property (T)
Oren Beker
11:00am|Remote Access

We show that if $G=\langle S | E\rangle$ is a discrete group with Property (T) then $E$, as a system of equations over $S$, is not stable (under a mild condition). That is, $E$ has approximate solutions in symmetric groups $Sym(n)$, $n \geq 1$, that...

Oct
27
2020

Computer Science/Discrete Mathematics Seminar II

On the extension complexity of random polytopes
10:30am|Simonyi 101 and Remote Access

Sometimes, it is possible to represent a complicated polytope as a projection of a much simpler polytope. To quantify this phenomenon, the extension complexity of a polytope P is defined to be the minimum number of facets in a (possibly higher...

Oct
26
2020

Analysis Seminar

Kolmogorov, Onsager and a stochastic model for turbulence
4:30pm|Remote Access

We will briefly review Kolmogorov’s (41) theory of homogeneous turbulence and Onsager’s (49) conjecture that in 3-dimensional turbulent flows energy dissipation might exist even in the limit of vanishing viscosity. Although over the past 60 years...

Oct
26
2020

Members’ Seminar

Paper Moebius Bands
2:00pm|Simonyi Hall 101 and Remote Access

You can make a paper Moebius band by starting with a $1$ by $L$ rectangle, giving it a twist, and then gluing the ends together. The question is: How short can you make $L$ and still succeed in making the thing? This question goes back to B. Halpern...

Oct
26
2020

Computer Science/Discrete Mathematics Seminar I

Fractionally Log-Concave and Sector-Stable Polynomials: Counting Planar Matchings and More
Nima Anari
11:15am|Remote Access - see Zoom link below

We introduce two new notions for polynomials associated with discrete set-valued probability distributions. These notions generalize well-studied properties like real-stability and log-concavity, but unlike them robustly degrade under a number of...