Organizers: Patrick Brosnan, Sandra Cerrai, and Vadim Kaloshin
Wednesday @ 3:15pm, Tea 2:45pm - 3:15 pm in room 3201
Math 3206 (Note: For the first part of Fall 2016, this room will be under construction, so the colloquium is temporarily moved to BPS 1250.)
From time to time special colloquia are held on other days, sometimes as part of conferences.
Other special colloquia are the Aziz Lectures and Avron Douglis Memorial Lectures.

Archives: 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017

  • A natural probabilistic model on the integers and its relation to Dickman-type distributions and Buchstab’s function

    Speaker: Ross Pinsky (Department of Mathematics, Technion) -

    When: Wed, September 7, 2016 - 3:15am
    Where: BPS 1250

    View Abstract

    Abstract: For each natural number N, let p_N denote the nth prime number, and let Omega_N denote the set of positive integers all of whose prime factors are less than or equal to p_N. Let P_N denote the probability measure on Omega_N for which P_N(n) is proportional to n. This measure turns out to have some very useful and interesting properties which are related to the theory of additive arithmetic functions.
    After recalling and discussing briefly some seminal results of this theory, such as those of Erdos-Wintner, Kac-Erdos and Hardy-Ramanujan, we will investigate P_N more closely. This will lead us to the Dickman function and "smooth" numbers, which are numbers without large prime factors, and to the Buchstab function and "rough" numbers, which are numbers without small prime factors. These two functions satisfy differential-delay equations. We obtain a new representation of the Buchstab function.
  • Path integral-based inference of PDEs and bond energies and mobility in Dynamic Force Spectroscopy

    Speaker: Tom Chou (University of California, Los Angeles) -

    When: Fri, September 16, 2016 - 3:15pm
    Where: BPS 1250

    View Abstract

    Abstract: A Bayesian interpretation is given for regularization terms for parameter functions in inverse problems. Fluctuations about the extremal solution depend on the regularization terms - which encode prior knowledge - provide quantification of uncertainty. After reviewing a general path-integral framework, we discuss an application that arises in molecular biophysics: The inference of bond energies and bond coordinate mobilities from dynamic force spectroscopy experiments.
  • Prange Prize Lecture: Some Intersections of Art and Science

    Speaker: Frank Wilczek (MIT) -

    When: Tue, September 20, 2016 - 4:00pm
    Where: 1412 Toll Physics
  • Introduction to rough paths techniques and applications

    Speaker: Samy Tindel (Purdue University) -

    When: Wed, September 21, 2016 - 3:15pm
    Where: BPS 1250

    View Abstract

    Abstract: The so-called rough paths theory can be seen as a technique which allows to define very general noisy differential systems with a minimum amount of probability structure.
    I will first give an introduction and some motivation for this area of research, and also highlight some of the main applications to stochastic differential equations and stochastic partial differential equations. Then I’ll try to explain the main mechanisms behind the rough paths method. I will eventually give some results about noisy differential systems which can be achieved from the rough paths perspective.

  • Held for department meeting

    Speaker: UMCP Math () -

    When: Fri, September 23, 2016 - 3:15pm
  • Held for department meeting

    Speaker: () -

    When: Wed, September 28, 2016 - 3:15pm
  • Held for department meeting

    Speaker: Hold () -

    When: Fri, October 14, 2016 - 3:15pm
    Where: Chem and Bio 0112
  • Held for department meeting

    Speaker: Held for Department Meeting (UMCP) -

    When: Wed, October 19, 2016 - 3:15pm
  • Held for department meeting

    Speaker: Held for Department Meeting (UMD) -

    When: Fri, October 21, 2016 - 3:15pm
  • Held Department

    Speaker: Held for Department Meeting () -

    When: Wed, October 26, 2016 - 3:15pm
  • Held For Department Meeting

    Speaker: Held for Department Meeting (UMD) -

    When: Mon, November 7, 2016 - 3:15pm
    Where: TBA
  • Held for Dept. Meeting

    Speaker: Held (UMD) -

    When: Wed, November 30, 2016 - 3:15pm
    Where: TBA
  • Local and Global Harmonic Analysis

    Speaker: Steve Zelditch (Northwestern University) -

    When: Fri, December 2, 2016 - 3:15pm
    Where: Room 0112 in the Chemistry/Biochemistry Building

    View Abstract

    Abstract: Harmonic analysis is about eigenfunctions of the Laplacian on Riemannian manifolds. It begins with Fourier analysis on Euclidean space or tori and proceeds to other metrics and manifolds. Local Harmonic analysis is about the analysis of eigenfunctions on `small balls' of radius equal to a few hundred wavelengths. Global Harmonic analysis uses the wave equation and geodesic flow. A well-known case is quantum chaos, which studies the effect of ergodicity of the geodesic flow on the structure of eigenfunctions. This talk is about recent results on nodal sets of eigenfunctions obtained by both local and global methods.
  • Modeling traffic flow on a network of roads (Aziz Lecture)

    Speaker: Alberto Bressan (Department of Mathematics, Penn State University) -

    When: Fri, December 9, 2016 - 3:15pm
    Where: CSIC 4122

    View Abstract

    Abstract: The talk will present various PDE models of traffic flow on a network of roads. These comprise a set of conservation laws, determining the density of traffic on each road, together with suitable boundary conditions, describing the dynamics at intersections.
    While conservation laws determine the evolution of traffic from given initial data, actual traffic patterns are best studied from the point of view of optimal decision problems, where each driver chooses his/her departure time and the route taken to reach destination. Given a cost functional depending on the departure and arrival times, a relevant mathematical problem is to determine (i) global optima, minimizing the sum of all costs to all drivers, and (ii) Nash equilibria, where no driver can lower his own cost by changing departure time or
    route to destination.
    Several results and open problems will be discussed.
  • Telegraph process with elastic boundary

    Speaker: Shelemyahu Zacks (SUNY Binghamton) -

    When: Wed, January 25, 2017 - 3:15pm
    Where: Kirwan Hall 3206

    View Abstract

    Abstract: A particle moves on the real line starting at the origin. It moves up for a random length of time at velocity V(t)=1. At that point it moves down at velocity V(t)=-1, for a random
    time. This alternately renewal process is a basic Telegraph process. The first time the particle returns to the origin it is absorbed with probability p or reflected up with probability 1-p. If the particle is reflected a new renewal cycle starts.
    We develop the distribution of cycle length and its moment. The distribution of the time till absorption and its moments.

  • A toy model for three-dimensional conformal probability

    Speaker: Abdelmalek Abdesselam (University of Virginia) -

    When: Wed, February 1, 2017 - 3:15pm
    Where: Kirwan Hall 3206

    View Abstract

    Abstract: The use of hierarchical or dyadic toy models is a common theme in analysis. The basic idea is to replace the real line by the leafs of an infinite tree. In harmonic analysis for instance, this can be done by replacing Fourier series with Walsh series. Results such as the Carleson-Hunt Theorem are still nontrivial in the hierarchical (Walsh)
    setting but they come in a cleaner form than in the Euclidean (Fourier) setting, thus allowing one to focus
    on the essential difficulties. I will present an elementary introduction to a similar hierarchical toy model for the simplest conformal quantum field theory in three dimensions. The latter corresponds to the critical scaling limit of the Ising model with long-range interactions. It has also been the subject of very recent investigations by physicists from the area known as the conformal bootstrap. The most elegant formulation of this toy model is in terms of
    p-adic numbers but my talk should be accessible to a wider audience with no prior knowledge of p-adics nor conformal quantum field theory.

  • TBA

    Speaker: David Donoho (FFT Talk) (Stanford) -

    When: Fri, February 17, 2017 - 3:15pm
    Where: TBA
  • TBA

    Speaker: Kavita Ramanan (Division of Applied Mathematics, Brown University) -

    When: Wed, March 1, 2017 - 3:15pm
    Where: Kirwan Hall 3206
  • TBA (Orr)

    Speaker: Daniel Orr (Virginia Tech) -

    When: Wed, March 29, 2017 - 3:15pm
    Where: MTH 0403
  • TBA

    Speaker: Yan Guo (Division of Applied Mathematics, Brown University) -

    When: Wed, April 5, 2017 - 3:15pm
    Where: Kirwan Hall 3206
  • TBA (Kirwan Undergraduate Lecture)

    Speaker: Indrid Daubechies (Duke University) -

    When: Fri, April 28, 2017 - 3:15pm
    Where: TBA

    View Abstract

    Abstract: TBA