Seminars Sorted by Series

In 2017 Lucio Galeati understood that a suitable scaling limit of certain hyperbolic PDEs with noise may lead to deterministic parabolic equations. Since then, in collaboration with Lucio and Dejun Luo, we have understood the phenomenon from several...

Given a polynomial $P$ of constant degree in $d$ variables and consider the oscillatory integral \[I_P = \int_{[0,1]^d} e(P(\xi)) \, \mathrm{d}\xi.\] Assuming the number $d$ of variables is also fixed, what is a good upper bound of $|I_P|$? In this...

We consider a system of $N$ particles evolving according to the gradient flow of their Coulomb or Riesz interaction, or a similar conservative flow, and possible added random diffusion. By Riesz interaction, we mean inverse power $s$ of the distance...

The study of hyperkaehler manifolds of lowest dimension (and of gauge theory on them) leads to a chain of generalizations of the notion of a quiver: quivers, bows, slings, and monowalls. This talk focuses on bows, their representations, and...

In this talk, we will discuss some joint work with Alexandru Ionescu on the nonlinear inviscid damping near point vortex and monotone shear flows in a finite channel. We will put these results in the context of long time behavior of 2d Euler...

Consider a point particle flying freely on the torus and elastically bouncing back from the boundary of fixed smooth convex obstacles. This is the celebrated Sinai billiard, a rare example of a deterministic dynamical system where rigorous results...

Mean curvature flow (MCF) is a geometric heat equation where a submanifold evolves to minimize its area. A central problem is to understand the singularities that form and what these imply for the flow. I will talk about joint work with Toby Colding...

Korevaar and Schoen introduced, in a seminal paper in 1993, the notion of `Dirichlet energy’ for a map from a smooth Riemannian manifold to a metric space. They used such concept to extend to metric-valued maps the regularity theory by Eells-Sampson...

A vast array of physical phenomena, ranging from the propagation of waves to the location of quantum particles, is dictated by the behavior of Laplace eigenfunctions. Because of this, it is crucial to understand how various measures of eigenfunction...

In the last two decades great progress has been made in the study of dispersive and wave equations. Over the years the toolbox used in order to attack highly nontrivial problems related to these equations has developed to include a collection of...

Joint work with Luc Hillairet (Orléans) and Emmanuel Trélat (Paris). A 3D closed manifold with a contact distribution and a metric on it carries a canonical contact form. The associated Reeb flow plays a central role for the asymptotics of the...

I will discuss the construction of continuous solutions to the incompressible Euler equations that exhibit local dissipation of energy and the surrounding motivations. A significant open question, which represents a strong form of the Onsager...

We present a new approach to some of the universality limits that arise in orthogonal polynomials. For example, we show that if w is a fixed weight positive a.e. in [-1,1], and w satisfies a Dini condition in some subinterval of (-1,1), then there...

An outstanding problem in "Quantum Chaos" is to understand the complexity of highly excited quantum states, and in particular of eigenfunctions of the Laplacian on a compact manifold. One attribute that can be studied is complexity of the nodal set...

We want to describe the eigenmodes of the Laplace-Beltrami operator on a compact Riemannian manifold of negative curvature, in the high-energy limit. In this aim, we study the semiclassical measures (a.k.a. quantum limits) associated with (infinite)...

In this talk I will go over a new approach to the Beurling-Selberg extremal problem for even functions based on the solution for the Gaussian and tempered distribution arguments. This provides interesting applications to analytic number theory...

Loop-erased random walk (LERW) is a random self-avoiding curve obtained by erasing the loops of a random walk according to chronological order. Studying LERW on the two-dimensional integer lattice, Schramm introduced a model of one-parameter planar...

We consider a system of trapped spinless bosons interacting with a repulsive potential and subject to rotation. In the limit of rapid rotation and small scattering length, we show that the ground state energy converges to that of a simplified model...

Abstract - TristanRoy.pdf

Over the past decades, much attention has been devoted to the detection of small inhomogeneities in materials or tissues, using non-invasive techniques, primarily electromagnetic wave-fields. The characterization of the signature of small inclusions...

Concentration phenomena for Laplacian eigenfunctions can be studied by obtaining estimates for their $L^{p}$ growth. By considering eigenfunctions as quasimodes (approximate eigenfunctions) within the semiclassical framework we can extend such...

I will discuss the problem of determining the number of infinite-volume ground states in the Edwards-Anderson (nearest neighbor) spin glass model on Z^D for D \geq 2. There are no complete results for this problem even in D=2. I will focus on this...

This talk will be a progress report on an ongoing research project which is joint work with Ajay Chandra and Gianluca Guadagni and which concerns a p-adic analog of the Brydges-Mitter-Scoppola phi-4 model with fractional Laplacian in 3 dimensions...

Band matrices are a class of random operators with rows and columns indexed by elements of the d-dimensional lattice, and random entries H(u, v) which are small when the distance between u and v on the lattice is larger than W. We shall discuss the...

As originally proposed by Anderson (1958), a quantum system of many local degrees of freedom with short-range interactions and static disorder may fail to thermally equilibrate, even with strong interactions and high excitation energy density. This...

Deift--Simon and Poltoratskii--Remling proved upper bounds on the measure of the absolutely continuous spectrum of Jacobi matrices. Using methods of classical approximation theory, we give a new proof of their results, and generalize them in several...

We develop the droplet scaling theory for the low temperature critical behavior of two-dimensional Ising spin glasses. The models with integer bond energies vs. continuously-distributed bond energies are in the same universality class in a regime of...

Using the spectral multiplicities of the standard torus, we endow the Laplace eigenspace with Gaussian probability measure. This induces a notion of a random Gaussian Laplace eigenfunctions on the torus. We study the distribution of nodal length of...