**Seminars and Colloquiums**

for the week of October 24, 2016

for the week of October 24, 2016

*SPEAKER:*

Thomas Weighill, UTK, Monday

Athmanathan Senthilnathan, UTK, Monday

David Horton, UTK, Wednesday

Cory Hauck, ORNL and UTK, Wednesday

Bo Gao, UTK, Thursday

Kylie Berry, UTK, Thursday

Professors Mariel Vazquez (U. of California, Davis) and Jose Perea (Michigan St. U.), Thursday

Steve Wise, UTK, Friday

Blackwell-Tapia Conference and Award Ceremony, Friday

*TEA TIME -
3:00 pm – 3:30 pm
Monday, Tuesday, & Wednesday
Room: Ayres 401*

*Hosted by: Elise Weir*

**Monday, October 24th**

TOPOLOGY/GEOMETRY SEMINAR

TITLE: Montone-light factorizations in coarse geometry II

SPEAKER: Thomas Weighill, UTK

TIME: 2:30pm – 3:20pm

ROOM: Ayres 114

Having defined coarsely light maps in the previous talk, in this talk we continue by defining coarsely monotone maps. We then recall the definition of the coarse category and show that coarsely monotone and coarsely light maps give a factorization system on this category. We look at some coarse properties preserved by coarsely light maps, and look briefly at a connection between the topological and coarse notions of monotone/light using the Higson corona.

MATH BIOLOGY SEMINAR

TITLE: Intraspecific Variation and Species Coexistence

SPEAKER: Athmanathan Senthilnathan, UTK

TIME: 2:30pm – 3:20pm

ROOM: Ayres G003

** Wednesday, October 26th**

ANALYSIS SEMINAR

TITLE: A Rough Approach to the Loewner Trace, Part II

SPEAKER: David Horton, UTK

TIME: 2:30pm - 3:20pm

ROOM: Ayres G003

We'll take a look at the trace of the Loewner Equation. Specifically, we'll see some results of Friz and Shekhar and discuss how they use rough path theory to show the existence of the trace.

COMPUTATIONAL AND APPLIED MATHEMATICS (CAM) SEMINAR

TITLE: A Simple Domain Decomposition Method for Fully Implicit Solutions of the Vlasov-Poisson System

SPEAKER: Cory Hauck, ORNL and UTK

TIME: 3:35pm – 4:35pm

ROOM: Ayres 113

The Vlasov-Poisson system provides a kinetic description of charged particles in electrostatic regimes. As such, it is fundamental to the study of non-equilibrium plasmas. In multiscale settings, it may be desirable to solve this system using implicit time integration techniques. In the case of Eulerian-type discretizations, such techniques can be a challenge to implement due to the complicated nature of the underlying characteristics in phase space. In this talk, I will present a simple domain decomposition approach which breaks cyclical dependencies in the discretized equations and thereby enables the use of sweeping techniques that are commonly used in radiation transport settings. The efficiency of the method is tested on several well-known benchmark problems in two-dimensional (one space + one velocity) and four-dimensional (two space + two velocity) settings.

** Thursday, October 27th**

ORAL SPECIALTY EXAMINATION

SPEAKER: Bo Gao

TIME: 1:00pm – 2:00pm

ROOM: Ayres 404

His committee consist of Professors: Chen (chair), Rajput, and Rosinski.

DIFFERENTIAL EQUATIONS SEMINAR

TITLE: An Asymptotically Compatible Scheme in 1-D

SPEAKER: Kylie Berry, UTK

TIME: 2:00pm – 3:00pm

ROOM: Ayres 112

When applying standard numerical approximation methods to problems that involve parameters, convergence consistent with the parameters is sometimes difficult to achieve. In the paper “Asymptotically Compatible Schemes and Applications to Robust Discretization of Nonlocal Models" by Tian and Du, the authors develop a general framework for creating an approximation schemes that is robust for a family of problems. The framework deals with a family of Hilbert spaces that have uniform embedding property, a bilinear form on each Hilbert space that is both bounded and coercive and a family of convergent approximations are asymptotically compatible with the spaces. Instead of discussing this general framework, we will apply the framework that they developed to the nonlocal 1-D homogenous Dirichlet boundary valued problem.

NIMBioS

SPECIAL UNDERGRADUATE EVENT

SPEAKER: Professors Mariel Vazquez (U. of California, Davis) and Jose Perea (Michigan St. U.)

TITLE: Mathematics: It’s Knot What You Think!

TIME: 5:30p – 7:00p

ROOM: NIMBioS, Hallam Auditorium, Claxton 206

Join two inspiring mathematicians—Dr. Mariel Vazquez, 2016 Blackwell-Tapia Award Winning

Mathematician from the University of California-Davis, and Dr. Jose Perea of Michigan State University, to learn about the fascinating field of topology, the mathematical study of properties preserved through deformations, twistings, and stretchings of objects. Experts in their field, Vazquez and Perea will discuss their career paths and the exciting applications of their work in pure mathematics, medicine, computers, engineering and more!

This event will be livestreamed to several math clubs at remote locations!

Pizza will be served prior!

** Friday, October 28th**

COLLOQUIUM

TITLE: Preconditioned Steepest Descent Methods for some Nonlinear Elliptic Equations Involving p-Laplacian Terms

SPEAKER: Steve Wise, UTK

TIME: 3:35pm-4:35pm

ROOM: Ayres 405

I will describe and analyze preconditioned steepest descent (PSD) solvers for fourth and sixth- order nonlinear elliptic equations that include p-Laplacian terms on periodic domains in 2 and 3 dimensions. The highest and lowest order terms of the equations are constant-coefficient, positive linear operators, which suggests a natural preconditioning strategy. Such nonlinear elliptic equations often arise from time discretization of parabolic equations that model various biological and physical phenomena, in particular, liquid crystals, thin film epitaxial growth and phase transformations. The analyses of the schemes involve the characterization of the strictly convex energies associated with the equations. I first give a general framework for PSD in generic Hilbert spaces. Based on certain reasonable assumptions of the linear pre-conditioner, a geometric convergence rate is shown for the nonlinear PSD iteration. I will then apply the general the theory to the fourth and sixth-order problems of interest, making use of Sobolev embedding and regularity results to confirm the appropriateness of our pre-conditioners for the regularized p-Lapacian problems. Our results include a sharper theoretical convergence result for p-Laplacian systems compared to what may be found in existing works. I will demonstrate rigorously how to apply the theory in the finite dimensional setting using finite difference discretization methods. Numerical simulations for some important physical application problems – including thin film epitaxy with slope selection and the square phase field crystal model – are carried out to verify the efficiency of the scheme.

This is joint work with W. Feng (UTK), A. Salgado (UTK), and C. Wang (UMassD).

BLACKWELL-TAPIA CONFERENCE AND AWARD CEREMONY

Friday afternoon and Saturday, Oct. 28 and 29, UT Conference Center

The conference and prize honors David Blackwell, the first African-American member of the National Academy of Science, and Richard Tapia, winner of the National Medal of Science in 2010, two seminal figures who inspired a generation of African-American, Native American and Latino/Latina students to pursue careers in mathematics. The Blackwell-Tapia Prize recognizes a mathematician who has contributed significantly to research in his or her area of expertise, and who has served as a role model for mathematical scientists and students from underrepresented minority groups, or has contributed in other significant ways to addressing the problem of underrepresentation of minorities in math.

The 2016 recipient of the Blackwell-Tapia Prize is Mariel Vazquez, Professor of Mathematics and Microbiology and Molecular Genetics at the University of California, Davis.

The conference includes scientific talks, poster presentations, panel discussion, ample opportunities for discussion and interaction, and the awarding of the Blackwell-Tapia Prize.

See this link http://www.nimbios.org/education/blackwell_tapia

Contact Suzanne Lenhart lenhart@math.utk.edu if you want to come and have not yet registered.

*If you are interested in giving or arranging a talk for one of our seminars or colloquiums, please review our calendar. *

*If you have questions, or a date you would like to confirm, please contact colloquium AT math DOT utk DOT edu *

**Past notices:**