# Faculty News Briefs

### March 2015

On March 24, 2015 Professor Matthew Dobson gave an invited talk titled “Derivation and Simulation of Nonequilibrium Langevin Dynamics” at Penn State at the SIAM Sponsored Workshop on Dimension Reduction: Mathematical Methods and Applications. On March 15 he presented a poster titled “Cell List Algorithms for Nonequilibrium Molecular Dynamics” at the SIAM Conference on Computational Science and Engineering.

During March 2015 Visiting Assistant Professor Ravi Kalpathy gave two talks. He gave a contributed talk on March 14 at the Probability Theory and Combinatorial Optimization conference at Duke University. On March 18 he gave a talk at the Seminar in Functional Analysis and Related Areas at the Catholic University of America. Both talks were titled “Degree Profile of m-ary Search Rrees: A Vehicle for Data Structure Compression.” Ravi had one refereed publication accepted in March 2015. His data science paper titled “Degree Profile of m-ary Search Trees: A Vehicle for Data Structure Compression” and co-authored with Hosam Mahmoud is scheduled to appear in *Probability in the Engineering and Informational Sciences*.

During the week of March 16-20, 2015 Professor Rob Kusner helped lead a workshop on "Small Clusters, Polymer Vesicles and Unusual Minima" at Brown University's ICERM.

Professor Michael Lavine was recently appointed to lead one of three teams drafting the American Statistical Association’s forthcoming position paper on P-values.

On March 10, 2015 Professor Franz Pedit gave a talk at the conference “Geometry of Smooth and Discrete Surfaces” at Technical University Berlin. His talk was titled “Integrable Surface Geometry for non-Abelian Topology.”

Professor Hongkun Zhang has been awarded a 2015 Simons Fellowship for her project titled “Stochastic Perspectives of Billiard Dynamics.” The awardees for 2015 are announced on the Simon’s Foundation web site. The Simons Foundation, established by noted mathematician and investor James H. Simons, awards fellowships annually to leading researchers in mathematics, theoretical physics, neuroscience, and other fields. The foundation awards a maximum of 40 fellowships in mathematics annually to faculty in the U.S., Canada, and the United Kingdom. The Fellows Program under the Simons Foundation Division for Mathematics and the Physical Sciences provides funds to faculty for up to a semester-long research leave from classroom teaching and administrative obligations. Simons Fellows are chosen based on research accomplishment in the five years prior to application and the potential scientific impact of the fellowship.

### February 2015

Professor Michael Lavine was recently appointed to the Editorial Advisory Board of stats.org, a non-profit, non-partisan project to analyze and explain numbers and statistics in the news and to promote statistical literacy in the media and society. It is a joint project of the American Statistical Association and Sense About Science USA.

On February 27, 2015 Emeritus Professor Floyd Williams gave a special lecture at Western New England University in Springfield, MA. The title of the talk was “8 Meets E8, Theta Series, 8 Visits the Elementary Particle Zoo, and Some Other Crazy Stuff.” The talk was part of a series of lectures that the department at Western New England University tries to present every other Friday to undergraduate students and faculty.

Professor Robin Young visited Georgia Tech during the period February 16–18, 2015. While he was there, he gave a talk titled “Asymptotic Expansion of Hyperbolic Evolution Operators” detailing recent progress on his long-standing project on the existence of shock-free periodic solutions of the compressible Euler equations.

### January 2015

Covering the period June 2014 – January 2015

In July 2014 Professor Tom Braden attended a workshop in geometric representation theory at RIMS in Kyoto, Japan. He gave a three-part minicourse on “Recent Developments in Modular Sheaf Theory” and a research talk titled “Ringel Duality and Perverse Sheaves on Hypertoric Varieties.”

Senior Lecturer Brian Burrell and Dr. Allan Ropper wrote a book titled *Reaching Down the Rabbit Hole*, which was published in 2014. The UK edition of the book was the BBC Radio4 book of the week during the week of January 12, 2015. An actor read 15-minute excerpts from the book each weekday morning over BBC 4 radio. During that week the book stayed in the top 50 on Amazon.uk, and on Sunday, January 25, the book hit the top ten list of the *Times of London* for non-fiction at #9.

In August 2014 Princeton University Press published a book titled *Hodge Theory* that Professor Eduardo Cattani edited together with Phillip Griffiths (Institute for Advanced Study), Fouad Elzein (Paris), and Le Dung Trang (Montpellier and ICTP). The book announcement can be viewed at http://press.princeton.edu/titles/10288.html.

In July 2014 Professor Matthew Dobson gave two talks. The first talk, titled “Algorithms for the Stochastic Simulation of Steady Nonequilibrium Flow,” was given at WWCM-ECCOMAS in Barcelona, Spain, and the second talk, titled “Generalized K-R Boundary Conditions for Steady Nonequilibrium Flow,” was given at PCMI in Park City, Utah.

The article by Professor Richard S. Ellis titled “Jewish Journeys: Decoding the Torah's Wisdom by Jewish Meditation” was published online by Jewish Currents <http://jewishcurrents.org/jewish-journeys-decoding-torahs-wisdom-buddhist-meditation-29011>. Richard wrote this article in conjunction with his appointment as an adjunct professor in the Department of Judaic and Near Eastern Studies at UMass Amherst.

Professor Panos Kevrekidis was honored by being elected a Fellow of the American Physical Society. Panos is cited for “fundamental contributions to the understanding of localized solutions, of their stability in nonlinear wave equations, and of their relevance to applications from atomic physics, nonlinear optics, and granular crystals.” Further information about this honor is available at http://www.umass.edu/newsoffice/article/two-umass-amherst-researchers-honored.

Professor Panos Kevrekidis had a busy summer. In late May 2014 he visited the University of Hamburg, giving an invited talk in the workshop on “Bose-Einstein Condensates in Waveguides: Curvature Meets Nonlinearity and Nonlocality.” He also visited the De Giorgi Center in Pisa, Italy, giving an invited lecture at the workshop on the “Stability of Solitary Waves.” Panos then visited collaborators at the University of Heidelberg in Germany during the month of July as well as collaborators at the University of Athens in Greece during August. In July Panos also participated in the AIMS Conference for Dynamical Systems in Madrid, Spain, and in August he participated in the SIAM Meeting on Nonlinear Waves and Coherent Structures in Cambridge, UK. Panos gave invited talks on his recent work on granular crystals at the conference in Madrid and on vortices in atomic condensates at the meeting in Cambridge. In Madrid he also co-organized, with Ricardo Carretero, a session on “Nonlinear Schrödinger Equations and Their Applications,” while in Cambridge he organized a session on “Novel Challenges in Atomic Gases: Bose-Einstein Condensates and Beyond.” During the academic year 2014–2015, Panos is visiting the Center for Nonlinear Studies of the Los Alamos National Laboratory in the capacity of the Stanislaw M. Ulam Distinguished Scholar. Prior to departing for his LANL post, in September Panos presented an Applied Mathematics Colloquium at the University of North Carolina and received the UMass Amherst Award for Outstanding Accomplishments in Research and Creative Activity at the 2014 Faculty Convocation.

During the second week of June 2014 Professor Rob Kusner visited colleagues at McGill University in Montreal, Canada, giving a two-hour lecture on June 13 titled “Linear Area Growth for CMC Surfaces in S^3.” Later in June and in July he was a research member of the IAS/PCMI program on Mathematics and Materials in Park City, Utah. Rob was invited to the Program on “Minimal Energy Point Sets, Lattices, and Designs” at the Erwin Schrödinger Institute in Vienna, Austria during the period October 12–18 in Vienna, Austria, where he spoke on “Coulomb Electrons on S^2 and the Möbius Energy of Hopf Links in R^3 and S^3.” He also gave a long seminar at Penn on November 11 and a colloquium at Lehigh on November 12 on the same topic. In addition Rob has been invited as a Research Professor for the spring 2016 Differential Geometry program at the Mathematical Sciences Research Institute in Berkeley. During January 2015 he began commuting back and forth to Brown University's Institute for Computational and Experimental Research in Mathematics to help organize its spring 2015 program on Phase Transitions and Emergent Properties.

Professor Andrea Nahmod was honored by being elected a Fellow of the American Mathematical Society in recognition of her “contributions to nonlinear Fourier analysis, harmonic analysis, and partial differential equations, as well as service to the mathematical community.” Further information about this honor is available at http://www.umass.edu/newsoffice/article/nahmod-named-fellow-american-mathematical.

Professor Michael Lavine reports on the following activities:

- He had two refereed publications accepted in the last half of 2014.
- Aaron Ellison, Michael Lavine, Peter Kerson, Audrey Barker Plotkin, and David Orwig, Building a Foundation: Land-Use History and Dendrochronology Reveal Temporal Dynamics of a
*Tsuga Canadensis*(Pinaceae) Forest,*Rhodora*116, No. 968. - Minji Park, David Reckhow, Michael Lavine, Erik Rosenfeldt, Benjamin Stanford, and Mi-Hyun Park, Multivariate Analyses for Monitoring EDCs and PPCPs in Lake Water,
*Water Environment Research*86, November.

- Aaron Ellison, Michael Lavine, Peter Kerson, Audrey Barker Plotkin, and David Orwig, Building a Foundation: Land-Use History and Dendrochronology Reveal Temporal Dynamics of a
- In the second half of 2014 he gave an invited talk titled “What is Bayesian Statistics and Why Everything Else is Wrong” in the Department of Mathematical Sciences at Worcester Polytechnic Institute in Worcester, MA.
- He wrote an article titled “Climate Change, Statistical Significance, and Science,” which comments on the improper use of statistics in a New York Times opinion piece. The article is posted at http://www.stats.org/climate-change-statistical-significance-and-science.

In September 2014 Professor Eric Sommers attended the workshop “Geometric Methods in Representation Theory” at Lancaster University in England, where he gave a talk titled “Exterior Powers of the Reflection Representation in Springer Theory.”

In July 2014 Professor Jenia Tevelev contributed several lectures to the summer school “Graduate Workshop on Moduli of Curves,” which was organized by Samuel Grushevsky, Robert Lazarsfeld, and Eduard Looijenga at the Simons Center for Geometry and Physics at Stony Brook University. The goal of the workshop was to introduce graduate students to the moduli theory of Riemann surfaces simultaneously from the viewpoints of algebraic geometry, topology, and Teichmüller theory. In September 2014 Jenia participated in a week-long conference “Tropicalization, Realization, and Algebraic-Tropical Correspondence” in Eilat, Israel. He delivered a talk “Non-Abelian and Spherical Tropicalization” based on his work and the work of his graduate student, Tassos Vogiannou.

### May 2014

Various department folk - including Professors Panos Kevrekidis, Rob Kusner, Andrea Nahmod and Floyd Williams - gave talks at the AMS Meeting in Albuquerque, New Mexico, April 5-6. Floyd gave a 40 minute talk entitled "Magnetic resolvent trace formula for 2d black hole vacua" in the "Topics in spectral geometry and global analysis" special session; Rob lectured on "Chirality for knots and fields" (after presenting a short video roasting "Physical Knots" special session honoree Jon Simon on his retirement); Panos spoke on "Dynamics of Nonlinear Waves in Granular Crystals" in his special session (going on to lecture in Los Alamos later that week); and Andrea talked about "Bilinear estimates... for the Ward system" in the "Harmonic Analysis" special session.

On April 23, Professor Rob Kusner was invited by the students of Commonwealth College to lead a "Faculty Chat" about "Bubbles" - about 40 students dropped in, enjoying pizza and chicken wings while performing bubble experiments and discussing the geometry of bubble surfaces with Rob.

Professor and Department Head Michael Lavine gave a talk on "Kernel Intensity Estimation of 2-Dimensional Spatial Poisson Point Processes from k-Tree Sampling" to the Virginia Tech statistics seminar April 10.

G. D. Birkhoff Professor William Meeks has a major paper on "Properly embedded minimal planar domains" (written with his Granada collaborators Joaquin Perez and Antonio Ros) appearing in the Annals of Mathematics this month. This is the sixth paper Bill has published in the Annals - arguably the premier journal in all of mathematics - over his distinguished career. Bill also gave a three-lecture mini-course on "Curvature and radius estimates for embedded CMC surfaces" at the March 2014 International Geometry Conference in Maceio, Brazil.

Professor Jenia Tevelev reports the following activities this semester: On January 30, his talk "Mori nightmare spaces" was delivered at Yale. From February 24 to 28 he gave two talks at the "Workshop on birational geometry and stability of moduli stacks and spaces of curves" held at the Vietnam Institute for Advanced Study in Mathematics in Hanoi, Vietnam. Jenia spoke on "Birational geometry of moduli of stable rational curves" at several venues: Michigan (March 19), Princeton (April 22) and Harvard (April 29). On April 26, he co-organized and led a panel discussion on undergraduate research with Sam Payne (Yale) and Jessica Sidman (Mt Holyoke)at the AGNES (Algebraic Geometry Northeastern Series) conference in Stony Brook. This professional development event was intended for - and attended by - all 170 conference participants: graduate students, postdocs and faculty.

### April 2014

During March 2014 Professor Richard S. Ellis gave two talks in the Department of Mathematics at the University of Illinois in Urbana-Champaign. On March 17 he gave a special presentation titled "Healing the Stress of Academic Life." On March 18 he gave a colloquium lecture titled "From Large Deviations to Statistical Mechanics: What Is the Most Likely Way for an Unlikely Event To Happen?"

On March 26 Professor Michael Lavine delivered the Sigma Xi talk at Smith College, "Before You Analyze, Know Y" about ensuring that statistical analyses match the data they're trying to represent.

For 30 hours over the weekend of March 28-30, about 70 Five Colleges undergraduate students participated in DataFest, wherein small teams compete to address a real-world problem supported by an interesting data set. DataFest is held at several locations around the country; the Five College event was held in LGRT 1634 and was organized by Andrew Bray.