# Math Calendar

 Categories: Choose a category... View all categories _______________________ Biomath Seminar Colloquium Computational Analysis Seminar Departmental Student Awards Faculty Meeting Graph Theory and Combinatorics Seminar Informal von Neumann Algebras Seminar Noncommutative Geometry and Operator Algebras Seminar Partial Differential Equations Seminar Subfactor Seminar Symplectic and Differential Geometry Seminar Topology and Group Theory Seminar Undergraduate Seminar Universal Algebra and Logic Seminar Vandy Math Club RSS

###### » Seminar Pages

February 26, 2013 7:00 pm (Tuesday)

## Nosocomial Epidemics, R0, and the Hippocratic Oath

Glenn Web, Vanderbilt University
Location: Stevenson 1206

nos-o-co-mi-al  (adjective)  - originating or occurring in a hospital
“get down R0, know your place, do not torment the human race”
primum non nocere – first, do no harm
Nosocomial epidemics are an increasing threat to society. The microbes that cause these epidemics are increasingly resistant to antibiotics. In the US they cause more than 100,000 deaths each year and that number is increasing. R0 (pronounced R-naught) is a quantity derived from mathematical models that predict the course of an epidemic. It is obtained from various parameters that determine the transmission dynamics of the infection. If R0 < 1, then the epidemic will abate. If R0 > 1, then the epidemic will worsen. The Hippocratic oath is the promise of physicians to not make the condition of a patient worse. It is the fundamental precept of medicine. I will tell you how all these are connected. I will also tell you how to avoid being infected by a nosocomial infection. Nosocomial infections occur in specific locations in the US, and only in these locations. You will never suffer a nosocomial infection if you do not go to one of these locations. I will tell you where these locations are.

February 26, 2013 4:10 pm (Tuesday)

## An Elementary Proof of the Completeness of the Lukasiewicz Axioms

Michael Botur, Palacký University Olomouc
Location: Stevenson 1312

The main aim of talk is twofold. Firstly, to present an elementary method based on Farkas' lemma for rationals on how to embed any finite partial subalgebra of a linearly ordered MV-algebra into \$\mathbb Q\cap [0,1]\$ and then to establish a new elementary proof of the completeness of the Lukasiewicz axioms. Secondly, to present a direct proof of Di Nola's Representation Theorem for MV-algebras and to extend his results to the restriction of the standard MV-algebra on rational numbers.

February 25, 2013 4:10 pm (Monday)

## ALE Ricci-Flat Kahler Surfaces and Weighted Projective Spaces

Rares Rasdeaconu, Vanderbilt University
Location: Stevenson 1432

We show that the explicit ALE Ricci-flat Kahler metrics constructed by Eguchi-Hanson, Gibbons-Hawking, Hitchin and Kronheimer, and their free quotients are Tian-Yau metrics. The proof relies on a construction of appropriate compactifications of Q-Gorenstein smoothings of quotient singularities as log del Pezzo surfaces. Time permitting, a geometric description of the compactifications will be provided. This is a joint work with I. Suvaina.

February 25, 2013 3:10 pm (Monday)

## Extension to an Even Triangulation

Kenta Noguchi, Keio University, Japan
Location: Stevenson 1432

A quadrangulation is a 2-cell embedded graph where every face is a quadrangle. An even triangulation is a 2-cell embedded graph where every face is a triangle and every vertex degree is even. A triangulation on the sphere is 3-chromatic if and only if it is an even triangulation. In this talk, we show that any quadrangulation can be extended to an even triangulation by adding diagonal edges to all quadrangle faces. We also determine the number of distinct even triangulations. This is joint work with Atsuhiro Nakamoto and Kenta Ozeki.

February 22, 2013 4:10 pm (Friday)

## Multibump Solutions of Nonlinear Schrödinger Equations with Steep Potential Well and Indefinite Potential

Zhongwei Tang, Beijing Normal University (visiting Vanderbilt University)
Location: Stevenson 1307

February 22, 2013 4:10 pm (Friday)

## Extended von Neumann Dimension for Representations of Equivalence Relations

Ben Hayes, UCLA
Location: Stevenson 1432

In past work, we define a notion of l^{p}-Dimension for uniformly bounded Banach space representations of a sofic group. This dimension is equal to the von Neuamn dimensnion, when H is a unitary representation of G contained in a multiple of the left-regular representation. We also computed this dimension for central natural representations of a sofic group, including direct sums of the translation action on l^{p}(G), and the multiplication action on L^{p}(L(G)). In this work, we shall explain how to define this notion of l^{p}-Dimension for representations of a sofic equivalence relation. When this equivalence relation satisfies a certain "finite presentation" assumption, we define an analogue of l^{2}-Betti numbers (or really l^{2}-Betti number +1) in the l^{p}-case. We can then connect some natural questions about this dimension with the cost versus l^{2}-Betti number conjecture.

February 21, 2013 4:10 pm (Thursday)

## Gabor Ridge Functions: Theory and Applications

Loukas Grafakos, University of Missouri
Location: Stevenson 5211

We discuss a directionally sensitive time-frequency decomposition and representation of functions. The coefficients of this representation allow one to measure the "amount'' of frequency the function (signal, image) contains in a certain time interval, and also in a certain direction. This has been previously achieved using a version of wavelets called ridge lets, but in this work we discuss an approach based on time-frequency or Gabor elements. Applications to image processing are discussed. Tea at 3:30 pm in SC 1425.

February 20, 2013 4:10 pm (Wednesday)

## Talk Title TBA

Yves Cornulier, Université Paris-Sud
Location: Stevenson 1310

February 20, 2013 3:10 pm (Wednesday)

## Talk Title TBA

Kamen Ivanov, University of South Carolina
Location: Stevenson 1307

February 20, 2013 1:30 pm (Wednesday)