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

  • Generative Adversarial Networks - RIT on Applied Harmonic Analysis

    Speaker: Dongmian Zou (UMD) -

    When: Mon, April 24, 2017 - 11:00am
    Where: MATH 2400
  • Wall-crossing for genus zero K-theoretic quasimap theory - Algebra-Number Theory

    Speaker: Fenglong You (Ohio State University) - https://math.osu.edu/people/you.111

    When: Mon, April 24, 2017 - 2:00pm
    Where: Kirwan Hall 1311

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    Abstract: For each positive rational number epsilon, we define K-theoretic epsilon-stable quasimaps to certain GIT quotients W//G. For epsilon>1, this recovers the K-theoretic Gromov-Witten theory of W//G introduced in more general context by Givental and Y.-P. Lee.

    For arbitrary \epsilon_1 and \epsilon_2 in different stability chambers, these K-theoretic quasimap invariants are expected to be related by wall-crossing formulas. We prove wall-crossing formulas for genus zero K-theoretic quasimap theory when the target W// G admits a torus action with isolated fixed points and isolated one-dimensional orbits.

  • An Ordered Line Integral Method for Hamilton-Jacobi Type Equations - RIT on Applied PDE

    Speaker: Daisy Dahiya (University of Maryland ) -

    When: Mon, April 24, 2017 - 3:00pm
    Where: Kirwan Hall 1311
  • Square roots of Thompson's group F - Geometry-Topology

    Speaker: Thomas Koberda (University of Virginia) - http://faculty.virginia.edu/Koberda/

    When: Mon, April 24, 2017 - 3:15pm
    Where: Kirwan Hall 1313

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    Abstract: I will discuss square roots of Thompson's group F, which are certain two-generator subgroups of the homeomorphism group of the interval, the squares of which generate a copy of Thompson's group F. We prove that these groups may contain nonabelian free groups, they can fail to be smoothable, and can fail to be finitely presented. This represents joint work with Y. Lodha.
  • On rank and isomorphism of von Neumann special flows - Dynamics

    Speaker: Anton Solomko (University of Bristol, UK) - https://people.maths.bris.ac.uk/~as14789/index.html

    When: Tue, April 25, 2017 - 2:00pm
    Where: Kirwan Hall B0427

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    Abstract: A von Neumann flow is a special flow over an irrational rotation of the circle and under a piecewise smooth roof function with a non-zero sum of jumps. Such flows appear naturally as special representations of Hamiltonian flows on the torus with critical points. We consider the class of von Neumann flows with one discontinuity. I will show that any such flow has infinite rank and that the absolute value of the jump of the roof function is a measure theoretic invariant. The main ingredient in the proofs is a Ranter type property of parabolic divergence of orbits of two nearby points in the flow direction.
    Joint work with Adam Kanigowski.
  • Limiting Configurations of Solutions of Hitchin Equation - Student Geometry and Topology

    Speaker: Xuesen Na (UMD) -

    When: Tue, April 25, 2017 - 3:00pm
    Where: Kirwan Hall 1310
  • The prescribed Ricci curvature problem on homogeneous spaces - Informal Geometric Analysis

    Speaker: Artem Pulemotov (University of Queensland) -

    When: Tue, April 25, 2017 - 4:00pm
    Where: Kirwan Hall 1308

    View Abstract

    Abstract: We will discuss the problem of recovering an invariant Riemannian metric on a compact homogeneous space from its Ricci curvature
  • On Stochastic Brinkman-Forchheimer Anisotropic 3D Navier-Stokes Equations - Probability

    Speaker: Annie Millet (Université Paris 1 Panthéon Sorbonne) - http://www.proba.jussieu.fr/dw/doku.php?id=users:millet:index

    When: Wed, April 26, 2017 - 11:00am
    Where: Kirwan Hall 3206
  • An afternoon in honor of Sergei Novikov (notice special schedule) - Dynamics

    When: Wed, April 26, 2017 - 2:00pm
    Where: MATH 3206

    View Abstract

    Abstract: see https://www-math.umd.edu/research/conferences/afternoon-of-geometric-analysis.html
  • On the Novikov higher signature conjecture: history and development - Lie Groups and Representation Theory

    Speaker: Gennadi Kasparov (Vanderbilt)

    When: Wed, April 26, 2017 - 2:00pm
    Where: Kirwan Hall 3206

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    Abstract: This is part of the Novikov celebration.
    The Novikov higher signature conjecture played and continues to play an important role in the development of several areas of mathematics: topology, geometric group theory, K-theory of C*-algebras. I will give a brief exposition of the history and progress in research related with the Novikov conjecture up to the most recent results.
  • Descriptive Set Theory: III - Student Logic Seminar

    Speaker: Douglas Ulrich (UMCP) -

    When: Wed, April 26, 2017 - 2:00pm
    Where: Math 1310
  • A discrete analog of the Novikov-Veselov hierarchy and its applications - Colloquium

    Speaker: Igor Krichever (Columbia) - http://www.math.columbia.edu/~krichev/

    When: Wed, April 26, 2017 - 3:15pm
    Where: Kirwan Hall 3206

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    Abstract: Spectral theory of the 2D Schrodinger operator on one energy level pioneered by Novikov and Veselov developed over the years is still full of open problems. In the talk I will present recent progress in this area and its application to a wide range of problems, including characterization of Prym varieties in algebraic geometry and the solution of a
    sigma SO(N) model in mathematical physics.

  • Dynamics of Granular Clogging - Applied Dynamics

    Speaker: Doug Durian (Department of Physics - University of Pennsylvania) - http://www.physics.upenn.edu/people/standing-faculty/douglas-durian

    When: Thu, April 27, 2017 - 12:30pm
    Where: ERF 1207
  • Lower bounds for Lyapunov exponents of flat bundles on curves - Dynamics

    Speaker: Anton Zorich (Institut Mathematiques de Jussieu, Paris, France) - https://webusers.imj-prg.fr/~anton.zorich/

    When: Thu, April 27, 2017 - 2:00pm
    Where: Kirwan Hall 1311

    View Abstract

    Abstract: (Joint work with A. Eskin, M. Kontsevich, M. Moeller)

    Consider a flat bundle over a complex curve. Associated Lyapunov
    exponents describe mean monodromy of the flat bundle along a random
    hyperbolic geodesic on the base; they play a role of dynamical
    analogs of characteristic numbers of the bundle.

    We prove a conjecture of Fei Yu that the sum of the top k Lyapunov
    exponents of the flat bundle is always greater or equal to the
    degree of any rank k holomorphic subbundle. We generalize the
    original context from Teichmuller curves to any local system over a
    curve with non-expanding cusp monodromies. As an application we
    obtain the large genus limits of individual Lyapunov exponents in
    hyperelliptic strata of Abelian differentials.

    Understanding the case of equality with the degrees of subbundle
    coming from the Hodge filtration seems challenging, e.g. for
    Calabi-Yau type families. We conjecture that equality of the sum of
    Lyapunov exponents and the degree is related to the monodromy group
    being a thin subgroup of its Zariski closure.
  • Ricci-flat Kahler metrics - RIT on Geometry and Physics

    Speaker: Matt Dellatorre (UMCP) -

    When: Thu, April 27, 2017 - 3:30pm
    Where: PHYS 1117

    View Abstract

    Abstract: We'll start to talk about Ch. 7 of the book.

  • Mathematics for art investigation (Kirwan Undergraduate Lecture) - Colloquium

    Speaker: Indrid Daubechies (Duke University) - https://math.duke.edu/people/ingrid-daubechies

    When: Thu, April 27, 2017 - 4:00pm
    Where: MTH 3206

    View Abstract

    Abstract: Mathematical tools for image analysis increasingly play a role in helping art
    historians and art conservators assess the state of conservation of paintings,
    and probe into the secrets of their history. The talk will review several case
    studies, Van Gogh, Gauguin, Van Eyck among others.
    https://www-math.umd.edu/research/kirwan-undergraduate-lectures.html
  • Mathematics for Art Investigation - Special Lecture

    Speaker: Ingrid Daubechies (Duke University) - https://math.duke.edu/people/ingrid-daubechies

    When: Thu, April 27, 2017 - 4:00pm
    Where: Kirwan Hall 3206

    View Abstract

    Abstract: Mathematical tools for image analysis increasingly play a role in helping art historians and art conservators assess the state of conversation of paintings, and probe into the secrets of their history. the talk will review several case studies, Van Gogh, Gauguin, Van Eyck among others.
  • Transversally elliptic operators and K-theory - Lie Groups and Representation Theory

    Speaker: Gennadi Kasparov (Vanderbilt)

    When: Fri, April 28, 2017 - 2:00pm
    Where: Kirwan Hall 3206

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    Abstract: The class of (pseudo-) differential operators transversally elliptic with respect to a Lie group action on a manifold was introduced by M. Atiyah in the 70s. He also made an attempt to obtain a formula which calculates the index of such operators by topological means. This class of operators is interesting both from the point of view of geometry and analysis, but particularly by its relations with representation theory of Lie groups. In the 90s, N. Berline and M. Vergne have obtained a certain very complicated index formula. However, this did not stop further attempts to obtain something more reasonable and more useful in applications. I will try to explain the background of the theory and a different approach to an index formula.
  • Surfing Wavelets - Colloquium

    Speaker: Indrid Daubechies (Duke) - https://math.duke.edu/people/ingrid-daubechies

    When: Fri, April 28, 2017 - 3:15pm
    Where: Kirwan Hall 3206

    View Abstract

    Abstract: Wavelets provide a mathematical tool that emerged in the 1980s from a synthesis of ideas in mathematics, physics, computer science and engineering. They are now used in a wide range of mathematical applications, and provide a mathematical way to "zoom in" on details, without losing track of the large picture. The talk will describe some of the essential features of the approach, and illustrate with examples.