Seminars Sorted by Series

Algebro-Geometric Derived Categories and Applications

Apr
29
2008

Algebro-Geometric Derived Categories and Applications

Categorification of quantum groups and Floer theory
Hao Zheng
2:00pm|S-101

This talk is concerned with categorification of quantum Kac-Moody algebras and their integrable representations. First, I show how to fulfill the task by using sheaf theory. Then I will argue that the constructions could be well understood and...

May
07
2008

Algebro-Geometric Derived Categories and Applications

Representations of Rational Cherednik Algebras and Miracles of Science
10:30am|S-101

I will report on a work in progress joint with Andrei Okounkov. We extend the methods developed in an earlier work with Mirkovic and Rumynin on modular representations of semi-simple Lie algebras to representation of symplectic reflection algebras...

Allen-Cahn/Ginzburg-Landau Reading group

Allen-Cahn/Ginzburg-Landau Reading Group

Amplitudes and Combinatorics Synergy Event

Oct
03
2024

Amplitudes and Combinatorics Synergy Event

10:00am|Rubenstein Commons | Meeting Room 5

Summary: This event aims to foster collaboration between combinatorialists and amplitudologists in two ways: first by bridging language and concept barriers, and second by highlighting open problems of mutual interest. 

Schedule:  Available here

Conta...

Oct
03
2024

Amplitudes and Combinatorics Synergy Event

10:00am|Rubenstein Commons | Meeting Room 5

Summary: This event aims to foster collaboration between combinatorialists and amplitudologists in two ways: first by bridging language and concept barriers, and second by highlighting open problems of mutual interest. 

Schedule:  Available here

Conta...

Analysis and Beyond: Celebrating Jean Bourgain’s Work and Its Impact

Analysis and Mathematical Physics

Oct
05
2022

Analysis and Mathematical Physics

Lipschitz Rigidity for Scalar Curvature
4:30pm|Simonyi 101 and Remote Access

Lower scalar curvature bounds on spin Riemannian manifolds exhibit remarkable rigidity properties determined by spectral properties of Dirac operators. For instance, a fundamental result of Llarull states that there is no smooth Riemannian metric on...

Oct
12
2022

Analysis and Mathematical Physics

Density Lower Bounds for Topologically Non-Trivial Minimal Cones
4:30pm|Simonyi 101 and Remote Access

I will discuss how to use mean curvature flow to give nearly optimal lower bounds on the density of topologically non-trivial minimal hypercones in low dimensions. This compliments work of Ilmanen-White who gave analogous bounds for topologically...

Oct
19
2022

Analysis and Mathematical Physics

On the Stability of the Fractional Caffarelli-Kohn-Nirenberg Inequality
4:30pm|Simonyi 101 and Remote Access

In this talk I will present a general framework to establish the stability of  inequalities of the form >= F(u); where L is a positive linear operator and F is a 2-homogeneous nonlinear functional.

We will then see how this framework can be...

Nov
02
2022

Analysis and Mathematical Physics

Geometric Measure Theory on Non Smooth Spaces with Lower Ricci Curvature Bounds
Daniele Semola
4:30pm|Simonyi 101 and Remote Access

There is a celebrated connection between minimal (or constant mean curvature) hypersurfaces and Ricci curvature in Riemannian Geometry, often boiling down to the presence of a Ricci term in the second variation formula for the area. The first goal...

Nov
16
2022

Analysis and Mathematical Physics

Branched Regularity Theorems for Stable Minimal Hypersurfaces Near Classical Cones of Density Q+1/2
4:30pm|Simonyi 101 and Remote Access

The presence of branch points and so-called density gaps heavily complicates the regularity theory for minimal submanifolds or, more precisely, stationary integral varifolds. Density gaps illustrate a mismatched symmetry between nearby varifolds...

Nov
30
2022

Analysis and Mathematical Physics

Decay for the Teukolsky Equation on Subextremal Kerr Black Holes
Rita Teixeira da Costa
3:00pm|Simonyi 101 and Remote Access

The Teukolsky equation is one of the fundamental equations governing linear gravitational perturbations of the Kerr black hole family as solutions to the vacuum Einstein equations. We show that solutions arising from suitably regular initial data...

Dec
07
2022

Analysis and Mathematical Physics

Three Things About Polynomials
4:30pm|Simonyi 101 and Remote Access

I will talk about three interesting ingredients that goes into the results on H\"{o}rmander type operators I presented at Princeton (joint with Shaoming Guo and Hong Wang). They are all related to algebraic or geometric properties of multivariate...

Dec
14
2022

Analysis and Mathematical Physics

Additive Energy of Regular Measures in One and Higher Dimensions, and the Fractal Uncertainty Principle
3:00pm|Simonyi 101 and Remote Access

We obtain new bounds on the additive energy of (Ahlfors-David type) regular measures in both one and higher dimensions, which implies expansion results for sums and products of the associated regular sets, as well as more general nonlinear functions...

Dec
14
2022

Analysis and Mathematical Physics

Classical Turbulence as Quantum Geometry
Alexander Migdal
4:30pm|Simonyi 101 and Remote Access

The loop equation for circulation PDF as functional of the loop shape is derived from the Hopf equation. This equation is $\textbf{exactly}$ equivalent to the Schrödinger equation in loop space, with viscosity playing the role of Planck's constant...

Jan
18
2023

Analysis and Mathematical Physics

Regularity of Vortex and SQG Patches
3:00pm|Simonyi Hall 101 and Remote Access

I will review some recent progress on regularity properties of vortex and SQG patches. In particular, I will present an example of a vortex patch with continuous initial curvature that immediately becomes infinite but returns to $(C^2)$ class at all...

Feb
08
2023

Analysis and Mathematical Physics

On Co-dimension One Stability of the Soliton for the 1D Focusing Cubic Klein-Gordon Equation
3:00pm|Simonyi Hall 101 and Remote Access

Solitons are particle-like solutions to dispersive evolution equations whose shapes persist as time evolves. In some situations, these solitons appear due to the balance between nonlinear effects and dispersion, in other situations their existence...

Feb
15
2023

Analysis and Mathematical Physics

Degenerate Dispersion and Illposedness for Generalized SQG Equations
Dr. In-Jee Jeong
3:00pm|Simonyi Hall 101 and Remote Access

Given a linear equation whose principal term is given by a degenerate dispersive pseudo-differential operator, we provide a framework for the construction of degenerating wave packet solutions. As an application, we prove strong ill-posedness for...

Feb
22
2023

Analysis and Mathematical Physics

A tricritical point in the Blume-Capel model
Trishen Gunaratnam
3:00pm|Simonyi Hall 101 and Remote Access

This talk will be about a ferromagnetic spin system called the Blume-Capel model. It was introduced in the '60s to model an exotic multi-critical phase transition observed in the magnetisation of uranium oxide. Mathematically speaking, the model can...

Mar
08
2023

Analysis and Mathematical Physics

The adjoint Brascamp-Lieb inequality
3:00pm|Simonyi Hall 101 and Remote Access

The Brascamp-Lieb inequality is a fundamental inequality in analysis, generalizing more classical inequalities such as Holder's inequality, the Loomis-Whitney inequality, and Young's convolution inequality: it controls the size of a product of...

Mar
22
2023

Analysis and Mathematical Physics

Diffusion and Mixing for Two-dimensional Hamiltonian Flows
Michele Coti-Zelati
3:00pm|Simonyi Hall 101 and Remote Access

We consider general two-dimensional autonomous velocity fields and prove that their mixing and dissipation features are limited to algebraic rates. As an application, we consider a standard cellular flow on a periodic box, and explore potential...

Apr
05
2023

Analysis and Mathematical Physics

Scattering for nonlinear wave equations
3:00pm|Simonyi Hall 101 and Remote Access

We construct solutions with prescribed radiation fields for wave equations with polynomially decaying sources close to the lightcone. In this setting, which is motivated by semi-linear wave equations satisfying the weak null condition, solutions to...

Apr
12
2023

Analysis and Mathematical Physics

Generalized Entropy Methods and Stability in Sobolev and Related Inequalities
Jean Dolbeault
3:00pm|Simonyi Hall 101 and Remote Access

This lecture is devoted to a survey on explicit stability results in Gagliardo-Nirenberg-Sobolev and logarithmic Sobolev inequalities. Generalized entropy methods based on carré du champ computations and nonlinear diffusion flows can be used for...

Apr
26
2023

Analysis and Mathematical Physics

Global Stability of Kaluza-Klein Spacetimes
Zoe Wyatt
3:00pm|Simonyi Hall 101 and Remote Access

Spacetimes formed from the cartesian product of Minkowski space and a flat torus play an important role as toy models for theories of supergravity and string theory. In this talk, I will discuss an upcoming work, joint with Huneau and Stingo...

May
03
2023

Analysis and Mathematical Physics

The Alt-Phillips Functional for Negative Powers
Daniela De Silva
3:00pm|Simonyi Hall 101 and Remote Access

We discuss a one-phase degenerate free boundary problem which arises from the minimization of the so-called Alt-Phillips functional $$\int_\Omega (|\nabla u|^2 + u^\gamma \chi_{\{u>0\}}) dx$$ for $\gamma \in (-2,0).$ We establish partial regularity...

May
17
2023

Analysis and Mathematical Physics

Resonances as a Computational Tool
Katharina Schratz
3:00pm|Simonyi Hall 101 and Remote Access

A large toolbox of numerical schemes for dispersive equations has been established, based on different discretization techniques such as discretizing the variation-of-constants formula (e.g., exponential integrators) or splitting the full equation...

Oct
20
2023

Analysis and Mathematical Physics

Lipschitz Graphs in Carnot Groups
2:30pm|Simonyi Hall 101 and Remote Access

Submanifolds with intrinsic Lipschitz regularity in Carnot groups (i.e.,
stratified groups endowed with a sub-Riemannian structure) can be
introduced using the theory of intrinsic Lipschitz graphs started years
ago by B. Franchi, R. Serapioni and F...

Oct
27
2023

Analysis and Mathematical Physics

Frobenius-Type Results on Submanifolds and Currents
2:30pm|Simonyi Hall 101 and Remote Access

The question of producing a foliation of the n-dimensional Euclidean space with k-dimensional submanifolds which are tangent to a prescribed k-dimensional simple vectorfield is part of the celebrated Frobenius theorem: a decomposition in smooth...

Nov
03
2023

Analysis and Mathematical Physics

Optimization Problem Over the Space of Functions with Second Order Bounded Variation
Camillo Brena
2:30pm|Simonyi Hall 101 and Remote Access

This talk is a discussion about the extremal points of the unit ball with respect to the Hessian-Schatten variation seminorm, i.e. the total variation of the second distributional differential with respect to the Schatten matrix norm. The main...

Nov
10
2023

Analysis and Mathematical Physics

Probabilistic Scaling, Propagation of Randomness and Invariant Gibbs Measures
Andrea Nahmod
2:30pm|Simonyi Hall 101 and Remote Access

In this talk, we will start by describing how classical tools from probability offer a robust framework to understand the dynamics of waves via appropriate ensembles on phase space rather than particular microscopic dynamical trajectories. We will...

Dec
08
2023

Analysis and Mathematical Physics

The Influence of Edges in First-Passage Percolation on Z^d
2:30pm|Simonyi Hall 101 and Remote Access

We study the probability that a geodesic passes through a prescribed edge in first-passage percolation on Z^d. Benjamini, Kalai and Schramm conjectured that this probability tends to zero as the length of the geodesic tends to infinity, as long as...

Dec
15
2023

Analysis and Mathematical Physics

PDE and Discrete Models of 2D Quantum Materials
2:30pm|Simonyi Hall 101 and Remote Access

We consider 2D quantum materials (non-magnetic and constant magnetic field cases), modeled by a continuum Schroedinger operator, whose potential is a sum of translates of an atomic well, centered on the vertices of a discrete subset of the plane...

Jan
26
2024

Analysis and Mathematical Physics

Hawking Mass Monotonicity for Initial Data Sets
2:30pm|Simonyi Hall 101 and Remote Access

An interesting feature of General Relativity is the presence of singularities which can occur in even the simplest examples such as the Schwarzschild spacetime. However, in this case the singularity is cloaked behind the event horizon of the black...

Feb
02
2024

Analysis and Mathematical Physics

Robin Harmonic Measure in Rough Domains
2:30pm|Simonyi Hall 101 and Remote Access

I will describe the construction of a harmonic measure that reproduces a harmonic function from its Robin boundary data, which is a combination of the value of the function and its normal derivative. I shall discuss the surprising fact that this...

Feb
09
2024

Analysis and Mathematical Physics

Existence of Four Minimal Spheres in S^3 with a Bumpy Metric
2:30pm|Simonyi Hall 101 and Remote Access

In 1982, S. T. Yau conjectured that there exists at least four embedded minimal 2-spheres in the 3-sphere with an arbitrary metric. In this talk, we will show that this conjecture holds true for bumpy metrics and metrics with positive Ricci...

Feb
16
2024

Analysis and Mathematical Physics

Quantitative Regularity Theory for the Axisymmetric Navier-Stokes Equations
2:30pm|Simonyi Hall 101 and Remote Access

In the search for possible blow-up of the incompressible Navier-Stokes equations, there has been much recent attention on the class of axisymmetric solutions with swirl. Several interesting structures of this system have led to regularity criteria...