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• Organizational meeting

  Speaker: Applied PDE group (University of Maryland, College Park) -
  

  When: Mon, August 31, 2020 - 3:00pm
  Where: Online seminar -- Email Jacob Bedrossian for a zoom link
  
• Escaping Wells and Related Content

  Speaker: Nick Paskal (University of Maryland, College Park) -
  

  When: Mon, September 14, 2020 - 3:00pm
  Where: Online
  
• Global well-posedness for focusing NLS on semiperiodic space

  Speaker: Zehua Zhao (University of Maryland, College Park) -
  

  When: Mon, September 21, 2020 - 3:00pm
  Where: Online
  
• An introduction to Geometric Measure Theory I

  Speaker: Antonio De Rosa (University of Maryland, College Park) -
  

  When: Mon, September 28, 2020 - 3:00pm
  Where: Online
  

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  Abstract: Contact Jacob Bedrossian, for zoom link
  
• Existence and uniqueness of global solutions for the Vlasov-Poisson-Fokker-Planck system

  Speaker: Stavros Papathanasiou (University of Maryland, College Park) -
  

  When: Mon, October 5, 2020 - 3:00pm
  Where: Online
  

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  Abstract: https://umd.zoom.us/j/98137029467?pwd=VmlXajFSY1MzNmhCeXR2VndEWWJQQT09
  
• An introduction to Geometric Measure Theory II

  Speaker: Antonio de Rosa (University of Maryland, College Park) -
  

  When: Mon, October 12, 2020 - 3:30pm
  Where: Online
  

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  Abstract: Zoom link: https://umd.zoom.us/j/98137029467?pwd=VmlXajFSY1MzNmhCeXR2VndEWWJQQT09
  
• Passive scalar turbulence and Lagrangian chaos pt. I

  Speaker: Jacob Bedrossian (University of Maryland) -
  

  When: Mon, October 19, 2020 - 3:00pm
  Where: Online
  

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  Abstract: https://umd.zoom.us/j/98137029467?pwd=VmlXajFSY1MzNmhCeXR2VndEWWJQQT09
  
• Lagrangian chaos and passive scalar turbulence

  Speaker: Jacob Bedrossian () -
  

  When: Mon, October 26, 2020 - 3:00pm
  Where: Online
  

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  Abstract: https://umd.zoom.us/j/98137029467?pwd=VmlXajFSY1MzNmhCeXR2VndEWWJQQT09
  
• Introduction to fully nonlinear elliptic equations

  Speaker: Yijing Wu (University of Maryland) -
  

  When: Mon, November 2, 2020 - 3:00pm
  Where: Online
  

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  Abstract: https://umd.zoom.us/j/98137029467?pwd=VmlXajFSY1MzNmhCeXR2VndEWWJQQT09
  
• Equilibration of attraction-repulsion models in collective dynamics

  Speaker: Ruiwen Shu (UMD) -
  

  When: Mon, November 9, 2020 - 3:00pm
  Where: Online
  

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  Abstract: In this talk I will discuss some recent results related to the large time behavior of first order models with pairwise attraction and repulsion. The first part concerns the Newtonian repulsion with confinement (joint work with Eitan Tadmor). We prove the uniqueness of steady states for convex radial confining potentials, and prove an algebraic equilibration rate by constructing a Lyapunov-type functional. The uniqueness result is extended to the attraction-repulsion case with Newtonian repulsion and near-quadratic attraction. The second part concerns general attraction-repulsion (joint work with Jose Carrillo). For potentials satisfying the linear interpolation convexity (LIC), we prove the radial symmetry of Wasserstein-$\infty$ local minimizers. With some further assumptions, we prove the uniqueness of Wasserstein-$\infty$ local minimizers. When applying to power-law potentials, it implies that the steady state constructed in Carrillo-Huang 16' is indeed the unique local minimizer.
  
  https://umd.zoom.us/j/98137029467?pwd=VmlXajFSY1MzNmhCeXR2VndEWWJQQT09
  
• Control problems in infinite dimensional spaces with applications to SPDE

  Speaker: Chi-Hao Wu (UMD) -
  

  When: Mon, November 16, 2020 - 3:00pm
  Where: Zoom -- Email for link
  

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  Abstract: In this talk I will talk about a framework for studying approximate controllability in infinite dimensional spaces. As an application, I will talk about how this framework can be used to deduce the topological irreducibility of SPDE, which is closely related to the unique ergodicity. This talk is based on the work by Glatt-Holtz, Herzog and Mattingly.
  
• Fractional Stokes operator on a bounded domain: Relation to fractional Sobolev spaces

  Speaker: Pranava Jayanti (University of Maryland, College Park) -
  

  When: Mon, December 7, 2020 - 3:00pm
  Where: Online
  
• Organizational meeting

  Speaker: Applied PDE group (University of Maryland, College Park) -
  

  When: Mon, February 1, 2021 - 3:00pm
  Where: Online seminar -- Email Antonio De Rosa for a zoom link
  
• Introduction to Almgren-Pitts min-max theory

  Speaker: Antonio De Rosa (UMD) - https://sites.google.com/view/antonioderosa/home
  

  When: Mon, February 15, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: I will present the Almgren-Pitts min-max theory to search for minimal hypersurfaces in a closed manifold .
  
• Introduction to Velocity Averaging

  Speaker: David Levermore (UMD) -
  

  When: Mon, February 22, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: TBA
  
• On the structure of a two fluid system with Coulomb interactions

  Speaker: Manoussos Grillakis (UMD) -
  

  When: Mon, March 1, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: I will look at two fluids which interact via a non-local potential. There is a certain structure which allows us to compare smooth solutions to nearby rougher ones. The idea, due to C. Dafermos, is to use the energy of the difference as a measure of the distance between two solutions. I will explain what is the structure that allows you to do this and why this is a natural consequence of a Geometric principle. This is joint work (in progress) with A. Tzavaras.
  
• Compensated compactness hyper-viscosity and open questions

  Speaker: Eitan Tadmor (UMD) -
  

  When: Mon, March 8, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: I will describe how the compensated compactness theory of Tartar-Murat can be used in two separate cases, to construct solutions for nonlinear scalar conservation laws without spatial BV bounds.
  The first case deals with 1D equations. The classical method is based on vanishing viscosity limits. I will focus on hyper-viscosity limits, showing that compensated compactness based on one entropy production bound yields convergence. The convergence of spectral viscosity and finite volume approximations are prototype examples for such BV-free constructions.
  A second case deals with solutions of 2D scalar equations: I will show that a judicious choice of two entropies entropy bounds will suffice.
  
• Rough Paths and Rough Integrals

  Speaker: Ran Tao (UMD) -
  

  When: Mon, March 22, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: I will give a brief introduction to the concept of the rough path and the rough integral and how they are associated with controlled differential equations and stochastic differential equations
  
• An isoperimetric problem with a competing nonlocal term

  Speaker: Yijing Wu (UMD) -
  

  When: Mon, March 29, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: We are interested in the isoperimetric problem in which the classical perimeter competes with a nonlocal interaction term. While the perimeter tries to aggregate the set E into a ball, the nonlocal term has the opposite effect. This competition leads to a non trivial problem in which even the existence of minimizers is not obvious. We will discuss some results on the classical Gamow’s liquid drop model of an atomic nucleus, and the problem when the usual perimeter is competing with a nonlocal singular term comparable to a fractional perimeter.
  
• BMO^{-1} and the Navier-Stokes equations

  Speaker: Stavros Papathanasiou (UMD) -
  

  When: Mon, April 5, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: TBA
  
• Dynamics of Particles on a Curve with Pairwise Hyper-singular Repulsion

  Speaker: Ruiwen Shu (UMD) -
  

  When: Mon, April 12, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: We investigate the large time behavior of $N$ particles restricted to a smooth closed curve in $\mathbb{R}^d$ and subject to a gradient flow with respect to Euclidean hyper-singular repulsive Riesz $s$-energy with $s>1$. We show that regardless of their initial positions, for all $N$ and time $t$ large, their normalized Riesz $s$-energy will be close to the $N$-point minimal possible energy. Furthermore, the distribution of such particles will be close to uniform with respect to arclength measure along the curve.
  
• Hormander's condition for hypoellipticity and Malliavin calculus

  Speaker: Chi-Hao Wu (UMD) -
  

  When: Mon, April 19, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: TBA
  
• Faraday waves in soft elastic solids

  Speaker: Giulia Bevilacqua (Politecnico di Milano) -
  

  When: Mon, May 10, 2021 - 3:00pm
  Where: Contact Antonio De Rosa
  

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  Abstract: Recent experiments have observed the emergence of standing waves at the free surface of elastic bodies attached to a rigid oscillating substrate and subjected to critical values of forcing frequency and amplitude. This phenomenon, known as Faraday instability, is now well understood for viscous fluids but surprisingly eluded any theoretical explanation for soft solids.
  In this talk, we characterize Faraday waves in soft incompressible slabs using the Floquet theory to study the onset of harmonic and subharmonic resonance eigenmodes. We consider a ground state corresponding to a finite homogeneous deformation of the elastic slab. We transform the incremental boundary value problem into an algebraic eigenvalue problem characterized by the three dimensionless parameters, that characterize the interplay of gravity, capillary and elastic waves. Remarkably, we found that Faraday instability in soft solids is characterized by a harmonic resonance in the physical range of the material parameters. This seminal result is in contrast to the subharmonic resonance that is known to characterize viscous fluids, and opens the path for using Faraday waves for a precise and robust experimental method that is able to distinguish solid-like from fluid-like responses of soft matter at different scales.