Time: 1:40-2:40 pm Wednesdays
Room: PSA 102
(unless otherwise specified)

Contact:  Slim Ibrahim - ibrahim@math.asu.edu

Spring 2006

Fall 2005

Spring 2005

Fall 2004

DATE

SPEAKER

TOPIC/ABSTRACT

September 27  

Slim Ibrahim
(Math. & Stat., ASU)

Title:  Singular sets and uniqueness of weak solutions of the Navier-Stokes system  

Abstract:
Tis talk is devoted to the class of ``suitable weak solutions" of the Navier -Stokes system. These are of great interest due to the "smallness" of their singular sets. I will discuss different schemes of construction of such solutions and I will stress on the fact that the well known Hopf's method of Galerkin approximation is not yet known to lead to suitability.
             

October 4      

  Slim Ibrahim
(Math. & Stat., ASU)
           

Title: Singular sets and uniqueness of weak solutions of the Navier-Stokes system. Part II      

Abstract: I will discuss the uniqueness of weak solutions to the Navier-Stokes system under assumptions about their singular sets.
First, we show that two weak solutions with the same initial state should coincide, once their (space-time) singular sets are disjoint. This includes the Serrin's weak-strong uniqueness result. When two weak solutions have the same singular set, we will discuss different extra assumptions to get the uniquness.    

October 11     

  Sergei Suslov
(Math. & Stat., ASU)
         

Title: Fundamental Equations of Quantum Mechanics I     

Abstract: A short review of the Schroedinger, Pauli and Dirac equations of quantum mechanics will be given together with some examples of their solutions.    

October 18     

  A. Mahalov & B. Nicolaenco
(Math. & Stat., ASU)
         

Title: 3D Navier-Stokes and Euler Equations with Uniformly Large Initial Vorticity:
Global Regularity and Three-dimensional Euler Dynamics      

Abstract:   

October 25     

  Sergei Suslov
(Math. & Stat., ASU)
         

Title: Fundamental Equations of Quantum Mechanics II     

Abstract: A short review of the Schroedinger, Pauli and Dirac equations of quantum mechanics will be given together with some examples of their solutions.   

November 1     

  Sergei Nikitin
(Math. & Stat., ASU)
         

Title: Generalized persistency of excitation     

Abstract: Many problems of system identification, learning, adaptation, parameter estimation and design of feedback controls can be reduced to linear feedback stabilization of a time-dependent vector. Due to such wide range of applications the result on stabilization should be valid for a wide variety of time-dependent vector fields. However the classical version, known as persistency of excitation imposes the restrictions that proved to be a burden for solutions of many important problems. In pursuit to overcome those restrictions the researchers constructed a number of improvements for the classical persistency of excitation conditions. The literature devoted to this subject is so vast that an attempt to survey the results of this field would lead to a one semester course instead of one seminar. The main topic of the talk is to formulate and prove a generalized version of persistence of excitation conditions. The main result of the talk was partially published in "International Journal of Mathematics and Mathematical Sciences", see Volume 2006, ArticleID 34569, pages 1-6.    

November 8     

  Matthias Hieber
(Technical University Darmstadt)
         

Title: The Navier-Stokes flow past rotating obstacles     

Abstract: