Seminars Sorted by Series

Diophantine approximation deals with quantitative and qualitative aspects of approximating numbers by rationals. A major breakthrough by Kleinbock and Margulis in 1998 was to study Diophantine approximations for manifolds using homogeneous dynamics...

Let $f: \mathbf C^2 \rightarrow \mathbf \C^2$ be a polynomial transformation. The dynamical degree of $f$ is defined as $\lim_n (\text{deg} f^n)^{1/n}$, where $\text{deg} f^n$ is the degree of the $n$-th iterate of $f$. In 2007, Favre and Jonsson...

Following Birkhoff's proof of the Pointwise Ergodic Theorem, it has been studied whether convergence still holds along various subsequences. In 2020, Bergelson and Richter showed that under the additional assumption of unique ergodicity, pointwise...

Ever since Furstenberg proved his multiple recurrence theorem, the limiting behaviour of multiple ergodic averages along various sequences has been an important area of investigation in ergodic theory. In this talk, I will discuss averages along...

We will discuss a version of the Green--Tao arithmetic regularity lemma and counting lemma which works in the generality of all linear forms. In this talk we will focus on the qualitative and algebraic aspects of the result.

In these two talks, I will discuss the structure of certain varieties that depend functorially on the choice of a finite-dimensional vector space. Examples include the variety of d-way tensors of "slice rank" at most k and the variety of degree-d...

In these two talks, I will discuss the structure of certain varieties that depend functorially on the choice of a finite-dimensional vector space. Examples include the variety of d-way tensors of "slice rank" at most k and the variety of degree-d...

In model theory Fraisse limits are certain highly homogeneous countable structures -- examples include the rational numbers as the unique dense linear order without endpoints, and the Rado graph as the "unique infinite random graph".  I will discuss...

The goal of this learning seminar is to explain some of the core model theoretic notions which are behind Tao’s algebraic regularity lemma about definable graphs in finite fields (Tao 2012).

We will assume minimal knowledge of model theory and...

We will survey general definitions and facts about ultrafilters, and how the algebraic operations on the integers extend to the space of ultrafilters. We will also discuss some applications in combinatorial number theory and ergodic theory.

The inverse theorem for the Gowers U^{s+1}-norms has a central place in modern additive combinatorics, but all known proofs of it are difficult and most do not give effective bounds.

Over this seminar and the next, I will give an outline of a proof...

The inverse theorem for the Gowers U^{s+1}-norms has a central place in modern additive combinatorics, but all known proofs of it are difficult and most do not give effective bounds.

Over this seminar and the next, I will give an outline of a proof...

The "intersectivity lemma" states that if a ∈ (0,1) and A_n, n ∈ N,  are measurable sets in a probability space (X,m) satisfying  m(A_n) ≥ a for all n, then there exist a subsequence n_k, k ∈ N, which has positive upper density and such that the...

The notion of strong stationarity was introduced by Furstenberg and Katznelson in the early 90's in order to facilitate the proof of the density Hales-Jewett theorem. It has recently surfaced that this strong statistical property is shared by...

A density theorem for L-functions is quantitative measure of the possible failure of the Riemann Hypothesis. In his 1990 ICM talk, Sarnak introduced the notion of density theorems for families of automorphic forms, measuring the possible failure of...

Sets of recurrence were introduced by Furstenberg in the context of ergodic theory and have an equivalent combinatorial characterization as intersective sets, an observation which has led to interesting connections between these areas.

Originally...

In 1976, Gérard Rauzy proved a characterization of deterministic numbers: y is deterministic iff for any normal number x, x+y is also normal. During my lecture I willdiscuss  how normal and deterministic numbers behave under arithmetic operations. ...

I'll introduce o-minimality from a user's perspective assuming zero background. I'll talk about some of the main examples of o-minimal structures: as a user of o-minimality your first goal is to find out whether your favorite set lives in one of...

I'll focus specifically on point counting results in o-minimal structures. I'll start with the classical theorem of Pila and Wilkie and move on to improved versions that only hold in the "sharp" variant of o-minimality.

A Hodge structure is a certain linear algebraic datum.  Importantly, the cohomology groups of any smooth projective algebraic variety come equipped with Hodge structures which encode the integrals of algebraic differential forms over topological...

Differential Galois groups are algebraic groups that describe symmetries of some systems of differential equations. The solutions considered can live in any differential field and thus a natural framework to consider such symmetries is the setting...

A Hodge structure is a certain linear algebraic datum.  Importantly, the cohomology groups of any smooth projective algebraic variety come equipped with Hodge structures which encode the integrals of algebraic differential forms over topological...

The goal of these lectures is to present the fundamentals of Simpson’s correspondence, generalizing classical Hodge theory, between complex local systems and semistable Higgs bundles with vanishing Chern classes on smooth projective varieties.

Ben Bakker explained to us how to construct moduli spaces of polarized Hodge structures, and then produced period maps associated to families of smooth projective varieties. However, in practice one often encounters a family of smooth varieties...

In 2011 Bourgain and Rudnick showed that if $\gamma$ is a curve of non-vanishing curvature on the 2d standard flat torus, then there are no Laplace eigenfunctions of arbitrarily large eigenvalues containing $\gamma$ in their nodal set. We show that...

Every o-minimal structure determines a collection of "tame" or "definable" subsets of $bbR^n$. We can then ask about the fragment of complex geometry present in the structure: Which holomorphic functions are definable, and which spaces are cut out...

During the 2026-27 academic year the School will have a special program on Conformally Symplectic Dynamics and Geometry. Michael Hutchings, University of California, Berkeley will be the Distinguished Visiting Professor.

The purpose of this special...