Mathematisches Forschungskolloquium 2019

  • PD Dr. Wolfram Just (Queen Mary University of London)
    "Transfer operator technique for analytic maps - Or: Chaos in the Hilbert space"
    11.04.2019, 16:00 Uhr, Raum 427 (Ulmenstr. 69, Haus 3)
    Kolloquiumsleiter: Prof. Dr. Jens Starke
  • Prof. Dr. Eduard Feireisl (Akademie der Wiss., Prag)
    "On weak--weak uniqueness for the isentropic Euler system"
    Abstract: We discuss uniqueness of certain weak solutions in the class of general (measure--valued) solutions for the isentropic Euler system. The weak solution is unique provided it belongs to a certain Besov class and its symmetric gradient satisfies a one--sided Lipschitz condition.
    10.04.2019, 15:00 Uhr,  HS 125 (Ulmenstr. 69, Haus 3)
    ​​​​​​Kolloquiumsleiter: Prof. Dr. Peter  Takac, Ph. D.
  • Prof. John Hogan (University of Bristol, UK)
    "The rough with the smooth; regularization of the Painlevé paradox"
    Abstract: When a piece of chalk is pushed across a blackboard, it can jump and judder, often accompanied by an unpleasant screeching noise. This unwanted phenomenon occurs in many engineering applications, including robotic manipulators. In 1905, Painlevé showed that the governing rigid body equations can produce a paradox: when the coefficient of friction exceeds a critical value, the rod appears to be driven the rigid surface.  In an attempt to resolve this paradox, a jump in vertical velocity called impact without collision (IWC), has been proposed. But this approach can itself produce contradictions. A more consistent approach is to relax the rigid body assumption in the neighbourhood of the contact point, by assuming compliance there. This regularization produces a singularly perturbed problem. In this talk, I will show that the compliant problem has three major  phases: the frictional torque compresses the compliant surface until the rod stops sliding, then the rod sticks, before finally leaving the surface. The rigid body problem has one non-hyperbolic point. Using blowup, I will show that the compliant problem has a canard at this point. 
    Joint work with Kristian Kristiansen (DTU). 
    21.03.2019, 13:00 Uhr, HS 326 (Ulmenstr. 69, Haus 3)
    Kolloquiumsleiter: Prof. Dr. Jens Starke
  • Dr. Konstantinos Spiliotis (National Technical University of Athens, Greece)
    "Equation Free Computations on Neuronal Networks: From Neuronal Interactions To Emergent Brain Dynamics."
    Abstract
    14.03.2019, 10:00 Uhr, Raum 427 (Ulmenstr. 69, Haus 3)
    Kolloquiumsleiter: Prof. Dr. Jens Starke
  • Prof. Dr. Faruk Gologlu (Charls University Prague)
    "Families which are not equivalent to APN permutations"
    Abstract: Almost Perfect Nonlinear (APN) functions are important in cryptography. We will present theoretical results on inequivalence of APN functions to permutations including Gold and Kasami families. We also present results which explain why it wasn't possible to generalize  the Kim function which is equivalent to the only known APN permutation on an even extension degree.
    12.03.2019, 14:00 Uhr, HS 228 (Ulmenstr. 69, Haus 3)
    Kolloquiumsleiter: Prof. Dr. Gohar Kyureghyan
  • Dr. Annalisa Iuorio (TU Wien)
    "Geometric Singular Perturbation Analysis of a Model for Micro-Electro Mechanical Systems (MEMS)"
    Abstract
    07.03.2019, 14:00 Uhr, HS 326 (Ulmenstr. 69, Haus 3)
    Kolloquiumsleiter: Prof. Dr. Jens Starke
  • Prof. Dr. Thomas Sunn Pedersen (Max-Planck-Institut für Plasmaphysik, IPP)
    "Neural Networks for the W7-X Experiment"

    23.01.2019, 15:00 Uhr, HS 228 (Ulmenstr. 69, Haus 3)
    Kolloquiumsleiter: Prof. Dr. Roger Labahn