# Faculty News Briefs

### February 2013

On January 17, 2013 Professor Rob Kusner gave a talk at the Geometry-Topology Seminar at University of Pennsylvania. The title of the talk was "Chirality for Curves."

On January 20 and 11, 2013 Professor Michael Lavine hosted an undergraduate extern, Rachel Venaglia, from Lafayette College. The purpose of an externship is to show a student what it's like to work in a job such as ours.

On November 12 and 14, 2012 Professor Andrea Nahmod gave an advanced mini-course consisting of a survey talk and a research talk at the University of Texas at Austin at the 2012/13 Thematic Program on nonlinear Schr√∂dinger equations and Bose gases from a multidisciplinary, integrative perspective. The program was organized by Thomas Chen and Natasa Pavlovic at UT Austin. The talks were titled "Almost Sure Well Posedness and Randomization in Nonlinear PDE, Parts I and II."

Professor Fernando Zalamea of Bogota, Columbia, a former Ph.D. student of Professor Emeritus Ernest Manes, published two books last year. He will also be a plenary speaker at the Peirce Centennial Congress at University of Massachusetts Lowell in July 2014.

On November 29, 2012 Professor Alexei Oblomkov gave a talk at the Geometry-Algebra-Singularities-Combinatorics Seminar at Northeastern University. During the period January 18-27, 2013 he attended the Winter School on Sheaves in Low Dimension and gave an invited talk.

During the period November 20-28, 2012 Professor Robin Young visited a colleague in Taiwan. He gave a talk at National Central University in Zhongli and a talk at National Chung Hsing University in Taichung. Both talks were titled "Some Exact Solutions of Hyperbolic Systems." During the winter break he also visited his long-time collaborator Blake Temple at University of California Davis.

On January 8, 2013 Visiting Assistant Professor Pengfei Zhang gave a talk at the Dynamical Systems Seminar at Northwestern University. The title of the talk was "Volume of the Set of Transitive Points of Partially Hyperbolic Diffeomorphisms."

### January 2013

Professor Rob Kusner spoke about "Critical Links and Unlinks" at the Isaac Newton Institute on December 5, 2012. At TU Darmstadt on December 17, he gave an informal seminar about his discovery of the first example of an unlink which is a local (but not global) minimum for ropelength.

Rob Kusner's recent collaboration with experimental physicists at the University of Colorado and theoretical physicists at the University of Pennsylvania resulted in an article to be published in the 10 January 2013 issue of Nature (and online 23 December 2012: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11710.html). Their work explains the complex patterns observed in 3-dimensional liquid crystals and is expected to lead to new materials that can be actively controlled. A press release prepared by the news offices of the three universities involved describes the significance of their work: http://phys.org/news/2012-12-liquid-crystal-future-applications-advance.html.

On December 12, 2012 Professor Michael Lavine attended a speed-dating event at Amherst College designed to match biologists and mathematicians with similar research interests. The Department conducted five interviews for a position in Topology and had its holiday party.

The paper "Entropic fluctuations in statistical mechanics: I. Classical dynamical systems" by Vojkan Jaksic, Claude-Alain Pillet, and Professor Luc Rey-Bellet belongs to the "Highly Downloaded Collection 2011" from the journal Nonlinearity. See http://iopscience.iop.org/0951-7715/page/Highly%20Downloaded%20Collection%202011 for more details.

Luc Rey-Bellet has been invited to join the editorial board of the Journal of Statistical Physics for the period 2013-2015. The Journal of Statistical Physics publishes original papers, review papers, and book reviews in all areas of statistical physics as well as in related fields concerned with collective phenomena in physical systems. It was founded in 1969 and is the leading journal in the field of statistical mechanics.

### December 2012

Professor Rob Kusner had a busy November abroad. On the 6th & 7th, Rob visited the University of Bristol, where he offered an extended lecture on "A Scattering Theory of Soap Bubbles" to their Theoretical Physics seminar. The following two days he visited the University of Wales in Aberystwyth, where he delivered a colloquium version of the soap-bubble-scattering talk and another seminar on applying meromorphic differentials to mathematical problems arising in materials science (smectics, tilings, and the like). On the 15th &16th, Rob was at the University of Warwick Maths Institute, where he lectured on the "Space of Soap Bubbles" in their Geometric Analysis seminar. He also said hello to former UMass Ph.D. student, Dmitriy Rumynin, who is an Associate Professor there now. On the 20th Rob was back at the Isaac Newton Institute in Cambridge and gave a "Space of Soap Bubbles" seminar in the Topological Dynamics Programme there, relating what might be called "Newton's Laws of Bubble Scattering" to the basic mathematical theorems in the field of constant mean curvature surfaces. Rob adapted this theme as his Kings College London colloquium lecture on the 23rd and in his lead-off plenary lecture at a workshop on "Geometric Structures in PDE" at the ICMat research center in Madrid, Spain, on the 27th. Finally, Rob served as "El Presidente" of a Ph.D. panel at the Universidad Autonoma de Madrid on the 29th. Rob had also been the First Reader of the dissertation.

On November 13, 2012 Professor John Staudenmayer gave an invited talk "Estimating Physical Activity with an Accelerometer: An Overview of Methods" at the 16th Congress of the Latin American Nutrition Society in Havana, Cuba.

Professor Emeritus Floyd Williams gave an invited colloquium talk at Idaho State University on November 2, 2012. The title of the talk was "Fourier Analysis, Scattering, and Mock Zeta Function of Certain Black Hole Vacua."

### November 2012

On October 8, 2012 Visiting Assistant Professor Christopher Chong gave at talk in the Applied Math and PDE Seminar at Drexel University in Philadelphia, PA. The title of the talk was "Modulation Equations in Nonlinear Lattices."

While in the UK this fall, Professor Rob Kusner lectured on "Chirality for Curves (and More)" at the International Center for Mathematical Sciences workshop on Tangled Fields in Edinburgh, Scotland during the week of October 16-20, 2012. Rob also gave the October 25 geometric analysis seminar at Imperial College London on "The Space of Soap Bubbles."

During the period November 11-16, 2012 Postdoctoral Research Associate Yannis Pantazis participated in the workshop Nonequilibrium Statistical Mechanics: Mathematical Understanding and Numerical Simulation, held in Banff International Research Station in Alberta, Canada. He presented a talk titled "Applications of Entropy Production and of Relative Entropy."

On October 14, 2012 Visiting Assistant Professor Pengfei Zhang gave a talk at Penn State University at the Semi-annual Workshop in Dynamical Systems and Related Topics. The talk was titled "Volume of the Set of Transitive Points of Partially Hyperbolic Diffeomorphisms."

### October 2012

Professor George Avrunin received the College of Natural Sciences Outstanding Service and Outreach Award, along with Alexander Schreyer from the Department of Environmental Conservation. This award was announced at the State of the College session on September 4, 2012; the formal presentation will take place at a later event.

On September 24, 2012 Professor Matthew Dobson gave a talk titled "A Langevin Dynamics for Systems Immersed in a Linear, Nonequilibrium Flow" at IWCCM 2012 (International Workshop on Computational Mechanics of Materials).

The book by Professor Richard S. Ellis, Blinding Pain, Simple Truth: Changing Your Life Through Buddhist Meditation, is the Silver Medal winner in the Self-Help category of the 2012 Florida Publishers Association President's Book Awards. Fifty-four medalists were awarded gold and silver medals in 20 categories on September 29, 2012.

During the period August 20-22, 2012 Professor Krista Gile was part of an Expert Consultation on Respondent-Driven Sampling at the Centers for Disease Control and Prevention in Atlanta, GA.

On September 21, 2012 Professor Rob Kusner gave a seminar about "A Simple Matrix Chirality Invariant for Curves" at the Isaac Newton Institute for Mathematical Sciences in Cambridge, UK. He is visiting there this fall.

Professor Ivan Mirkovic is a member of the editorial boards of Glasnik Matematicki, Journal of Number Theory, Selecta Mathematica, and Transformation Groups. During the summer he attended a conference on Symplectic Algebraic Geometry in Luminy, France and a conference on Infinite Dimensional Lie Algebras in Montreal , Canada. In Montreal he gave a talk titled "Modular Representations and Koszul Diality."

Professor Andrea Nahmod reports on the following activities:

She delivered an invited lecture at the meeting on Evolution Equations, held in honor of Terence Tao's being awarded the Nemmers Prize. The meeting took place at Northwestern University in Evanston IL during the period May 4-6, 2012.

Professor Nahmod gave a talk titled "Almost Sure Existence of Global Weak Solutions for the Supercritical Navier-Stokes Equations" at the meeting on Nonlinear Evolution Problems held at the Oberwolfach Institute of Mathematics in Germany during the period May 13-19, 2012.

Professor Nahmod was the lead organizer and the chair of the Committee for the Conference on Challenges in Analysis, Geometry and Computation: High Dimensional Synthesis. This conference was in honor of Ronald R. Coifman, Peter W. Jones, and Vladimir Rokhlin. It was held at Yale University during the period June 4-6, 2012, and it was funded by grants (co-PI) from NSF, ONR, and Yale University. Between 200 and 250 people participated.

Professor Nahmod was awarded NSF grant DMS-1201443, "New Challenges in Nonlinear PDEs," for the period July 2012 - 2015. She is the principal PI on this grant.

She is a Co-Editor of Recent Advances in Harmonic Analysis and Partial Differential Equations, AMS Contemporary Mathematics Series, Volume 58, August 2012. Also, in February 2012, Professor Nahmod became an Associate Editor of Potential Analysis Journal, which is published by Springer. L. Saloff-Cost is the Editor in Chief.

On August 24, 2012 Allison J. Tanguay, Professor Nahmod's doctoral student at UMass Amherst, defended her Ph.D. thesis titled "New Bilinear Estimates for Quadratic-Derivative Nonlinear Wave Equations in 2+1 dimensions."

Nathan Senecal, Professor Nahmod's Capstone honors student, wrote a thesis on Nonlinear Fourier Analysis and was accepted into several Ph.D. program in mathematics. After narrowing down his choices to Princeton University, University of California at Berkeley, and UCLA, in fall 2012 he entered the Ph.D. program at UCLA, where he will work with Terence Tao.

Derek Wood, Profesor Nahmod's Capstone honors student, wrote a thesis on Nonlinear Dispersive PDEs. In fall 2012 he entered the Ph.D. program at the University of Michigan in Ann Arbor. His final choices were between the latter university and University of Wisconsin in Madison.

The AMS has initiated the Fellows of the American Mathematical Society program, of which the first group will be officially inducted during the Joint Meetings in San Diego, CA in January 2013. Professor Emeritus Floyd Williams was invited to be part of that group, which honors "distinguished contributions to mathematics." Details of the Fellows of the AMS program can be found at http://www.ams.org/profession/ams-fellows.