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All Colloquia & Seminars

Current Seminars

  1. Water waves and other interface problems (Part 1): Long time dynamics of space periodic water waves

    Location: MSRI: Online/Virtual
    Speakers: Massimiliano Berti (International School for Advanced Studies (SISSA/ISAS))

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657

    Abstract:

    In this seminar I will describe the existence of time quasi-periodic traveling solutions for the water waves equations of a bi-dimensional fluid, periodic in the space variable, with constant vorticity under the action of gravity and eventually capillary forces at the free surface.

    Updated on May 07, 2021 04:50 PM PDT

Upcoming Seminars

  1. Graduate Student Working Group: No Pure Capillary Solitary Waves Exist in 2D Finite Depth & Linear Instability in Fluid Free Surface Problems

    Location: MSRI: Online/Virtual
    Speakers: Xiao Liu (Georgia Institute of Technology), Ben Pineau (University of California, Berkeley)

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657


    Ben Pineau (University of California, Berkeley)

    Title:  No Pure Capillary Solitary Waves Exist in 2D Finite Depth

    Abstract:  We prove that the 2D finite depth capillary water wave equations admit no solitary wave solutions (with appropriate averaged decay at infinity). This closes the existence/non-existence problem for solitary water waves in 2D, under the classical assumptions of incompressibility and irrotationality, and with the physical parameters being gravity, surface tension and the fluid depth.

    Xiao Liu (Georgia Institute of technology)

    Title: Linear Instability in Fluid Free Surface Problems

    Abstract: We consider a class of shear flows in 2d capillary gravity water wave problem with flat bottom. We analyze in details the eigenvalue distribution of linearized system and the linear flow it generates. This is a joint work with Chongchun Zeng.

    Updated on May 07, 2021 08:43 AM PDT
  2. Euler/Navier Stokes (Part 1): Convergence of the vanishing viscosity limit for one-dimensional compressible fluids

    Location: MSRI: Online/Virtual
    Speakers: Matthew Schrecker (King's College London)

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657

    Abstract: The compressible Euler equations, modelling the flow of an inviscid gas, are well known to exhibit a number of complex phenomena that make the questions of well- or ill-posedness difficult to resolve in general. In particular, the presence and formation of shock waves in solutions to the Euler equations makes the question of which class of functions to look for solutions a subtle one. One conjectured class for possible well-posedness is that of the vanishing viscosity limit from the compressible Navier-Stokes equations. In this talk, I will present recent work (joint with Simon Schulz) on the existence of solutions to the 1D isentropic Euler equations in this class of solutions and draw connections to several other related works.

    Updated on May 06, 2021 09:22 AM PDT
  3. Euler/Navier Stokes (Part 2): Lagrangian Interior Regularity Result for the Incompressible Rotational Free Boundary Euler Equation with Surface Tension

    Location: MSRI: Online/Virtual
    Speakers: Amjad Tuffaha (American University of Sharjah)

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657

    Lagrangian Interior Regularity Result for the Incompressible Rotational Free Boundary Euler Equation with Surface Tension

    We investigate existence of local-in-time solutions to the Free boundary incompressible Euler equations with surface tension under minimal regularity assumptions on the initial data. We study the Lagrangian formulation of the system and do not assume irrotationality on the initial data. This is joint work with  Marcelo Disconzi and Igor Kukavica.

     

    Updated on May 07, 2021 07:39 AM PDT
  4. Fellowship of the Ring, National Seminar:

    Location: MSRI: Online/Virtual

    To attend this seminar, you must register in advance, by clicking HERE.

    Updated on Jan 11, 2021 04:36 PM PST
  5. Applied fluids: Mathematical modeling of aquifers

    Location: MSRI: Online/Virtual
    Speakers: Catherine Choquet (Université de La Rochelle)

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657

    Contamination of soil and groundwater is a major concern that affects all populated areas. However, this subject is not known for mathematical challenges in fluid dynamics, probably because the dynamics of water in an aquifer is extremely slow. But this slowness is precisely a problem because groundwater pollution can be rapid and its remediation very long. A challenge is therefore to develop models to monitor the vulnerability of aquifers in a context of very heterogeneous time scales.

    A large amount of research has been conducted on each of the involved processes (for example, geological, physical, or chemical), so that it may be argued that the corresponding model is already available. Nevertheless, there is such a wide variety of processes (chemical, hydrogeological, and anthropic) acting in such a wide range of temporal and geometrical length scales that the combination of the corresponding model components, if regarded as toolboxes in a software application, is, at best, computationally expensive. And unfortunately, our mathematical skills to manage the corresponding systems of nonlinear, degenerate and strongly coupled pdes are also weak.

    In this talk we present some recent developments and open problems for the mathematical handling (modelling, numerical recipes and theory!) of groundwater. We derive and analyse nonlinear moving boundary problems describing the exchanges between the overland and the underground water, saltwater intrusion in coastal areas, agricultural, industrial, or sewage pollution…

     

    Updated on May 07, 2021 08:03 AM PDT
  6. Water waves and other interface problems (Part 1): Flexural-gravity waves generated by moving loads on ice plates

    Location: MSRI: Online/Virtual
    Speakers: Emilian Parau (University of East Anglia)

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657

     

    Three-dimensional waves generated by moving loads on top of floating ice plates are investigated. The ice plates are modelled using the thin plate theory. Different viscoelastic models for the ice will be presented and wave patterns will be calculated. Nonlinear steady waves will be computed using boundary integral methods. Fully dispersive weakly nonlinear equations will also be derived and comparisons of solutions with field observations will be provided. Other related flows will be discussed.

    Updated on May 10, 2021 03:13 PM PDT
  7. Fellowship of the Ring, National Seminar:

    Location: MSRI: Online/Virtual

    To attend this seminar, you must register in advance, by clicking HERE.

    Updated on Jan 11, 2021 04:37 PM PST
  8. Applied fluids: Modelling Compressible Two-Phase Flow across Scales using Sharp and Diffuse Interface Ideas

    Location: MSRI: Online/Virtual
    Speakers: Christian Rohde (Universität Stuttgart)

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657

    Abstract: In the lecture we will consider the multi-scale modeling and  numerics for compressible two-phase flow. A sharp-interface approach appears to be adequate on a continuum scale where phase boundaries are fully resolved. This results in a concept using the compressible Euler equations in the bulk domains and understanding the phase boundary as a  discontinuous (shock) wave. We propose a numerical algorithm that relies on new exact solutions of special Riemann problems accounting for molecular-scale information to determine the phase dynamics.  
    Two-phase flow with topological changes can hardly be accessed by the  sharp-interface ansatz. In the second part of the lecture we will therefore present a class of diffuse-interface models that build on the  classical compressible Navier-Stokes-Korteweg model. We will show that these models can provide the basis for reliable computations of  convection-dominated  processes (e.g. droplet collision). Moreover, this diffuse-interface ansatz is compatible with homogenization techniques. Therefore we will conclude the lecture with a discussion of up-scaling compressible two-phase flow in porous media.

    Updated on May 10, 2021 02:48 PM PDT
  9. Euler/Navier Stokes (Part 1): Recent results on the instability of boundary layer models

    Location: MSRI: Online/Virtual
    Speakers: David Gerard-Varet (Université de Paris XI)

    To participate in this seminar, please register here: https://www.msri.org/seminars/25657

    Many hydrodynamic instabilities take place near a solid boundary at high Reynolds number. This reflects into the mathematical theory of the classical Prandtl model for the boundary layer: it exhibits high frequency instabilities, limiting its well-posedness to infinite regularity (Gevrey) spaces. After reviewing shortly this fact, we will turn to the Triple Deck model, an improvement of the Prandtl system that is commonly accepted to be more stable. We will show that this is actually wrong, and that the recent result of analytic well-posedness by Iyer and Vicol is more or less optimal.
    This is based on joint work with Helge Dietert.

    Updated on Apr 23, 2021 09:25 AM PDT
  10. Fluid Dynamics Farewell Tea

    Location: MSRI: Online/Virtual
    Updated on Apr 22, 2021 10:28 AM PDT
  11. Fellowship of the Ring, National Seminar:

    Location: MSRI: Online/Virtual

    To attend this seminar, you must register in advance, by clicking HERE.

    Updated on Jan 11, 2021 04:37 PM PST
  1. 2021 African Diaspora Joint Mathematics Workshop

    The African Diaspora Joint Mathematics Workshop (ADJOINT) will take place at the Mathematical Sciences Research Institute in Berkeley, CA from June 21 to July 2, 2021.

    ADJOINT is a two-week summer activity designed for researchers with a Ph.D. degree in the mathematical sciences who are interested in conducting research in a collegial environment.  

    The main objective of ADJOINT is to provide opportunities for in-person research collaboration to U.S. mathematicians, especially those from the African Diaspora, who will work in small groups with research leaders on various research projects. 

    Through this effort, MSRI aims to establish and promote research communities that will foster and strengthen research productivity and career development among its participants. The ADJOINT workshops are designed to catalyze research collaborations, provide support for conferences to increase the visibility of the researchers, and to develop a sense of community among the mathematicians who attend. 

    The end goal of this program is to enhance the mathematical sciences and its community by positively affecting the research and careers of African-American mathematicians and supporting their efforts to achieve full access and engagement in the broader research community. 

    Each summer, three to five research leaders will each propose a research topic to be studied during a two-week workshop.

    During the workshop, each participant will: 

    • conduct research at MSRI within a group of four to five mathematicians under the direction of one of the research leaders 
    • participate in professional enhancement activities provided by the onsite ADJOINT Director 
    • receive funding for two weeks of lodging, meals and incidentals, and one round-trip travel to Berkeley, CA 

    After the two-week workshop, each participant will:

    • have the opportunity to further their research project with the team members including the research leader 
    • have access to funding to attend conference(s) or to meet with other team members to pursue the research project, or to present results 
    • become part of a network of research and career mentors

    Updated on Mar 11, 2021 01:48 PM PST

Past Seminars

  1. Seminar ADJOINT Research Seminar: Validated Computation of Special Mathematical Functions

    The advent of reliable computing machines, computer algebra systems, and multiple precision computational packages diminished the need for tables of reference values for computing function values by interpolation, but today's numerical analysts, scientific researchers, and software developers still need a way to confirm the accuracy of numerical algorithms that compute mathematical function values. The field of validated computation of mathematical functions explores the development of multiple precision codes that compute certifiably accurate function values that can be used to test the accuracy of function data from personal, commercial, or publicly available codes. We discuss the analysis used to obtain reliable error bounds for floating point approximations and describe the implementation of the work in a publicly available beta site. 

    Updated on Mar 23, 2021 09:01 AM PDT
There are more then 30 past seminars. Please go to Past seminars to see all past seminars.