Past Events

The word complexity function p(n) of a subshift X measures the number of n-letter words appearing in sequences in X, and X is said to have linear complexity if p(n)/n is bounded. It's been known since work of Ferenczi that linear word complexity...

We say that a knot is slice if it bounds a smooth disk in 4-ball and ribbon if it bounds a ribbon disk in 3-sphere. Ribbon knots are always slice, while it is unknown whether the converse, also known as the slice-ribbon conjecture, is true. The...

Cell locomotion is essential for early development, angiogenesis, tissue regeneration, the immune response, and wound healing in multicellular organisms, and plays a very deleterious role in cancer metastasis in humans. Locomotion involves the...

We will explore how a Fourier optimization framework may be used to study two classical problems in number theory involving Dirichlet characters: The problem of estimating the least character non-residue; and the problem of estimating the least prime...

The memory capacity of a statistical model is the largest size of generic data that the model can memorize and has important implications for both training and generalization. In this talk, we will prove a tight memory capacity result for two-layer...

A polytope is the convex hull of finitely many points. A polytope is simplicial if all of its faces are simplices. What partial information about a simplicial polytope P is enough to uniquely determine P (up to certain equivalences)? We will discuss...

The formalization of string diagrams, in a 1991 paper by Andre Joyal and Ross Street, was a seminal event. They defined a basic diagrammatic language and proved its validity for rigorous mathematics in any monoidal category, and in doing so they laid...

The even filtration, introduced by Hahn-Raksit-Wilson, is a canonical filtration attached to a commutative ring spectrum which measures its failure to be even. Despite its simple definition, the even filtration recovers many arithmetically important...

In this seminar we recall the spectral partitioning method based on a Fiedler vector, i.e., an eigenvector corresponding to the second smallest eigenvalue of the Laplacian matrix of a graph. This problem corresponds to the minimization of a quadratic...

The derivation of effective macroscopic theories approximating microscopic systems of interacting particles is a major question in non-equilibrium statistical mechanics. For non-interacting particles this is a relatively easy task. However when...