# Faculty News Briefs

### May 2018

Calden named Instructional Innovation Fellow

Four faculty from the College of Natural Sciences, including our own Senior Lecturer Adena Calden, were recently selected through a highly competitive process to participate in the Summer 2018 Innovate@ Symposium that runs 21-24 May 2018. These symposia, led as a collaboration between TEFD, UMass Libraries, and IT, provide a unique opportunity to have hands-on instruction, to work with colleagues, and then try out the tools. Symposia members will also become part of an innovation think tank as Innovation Fellows that will be brought together to consider new instructional innovations throughout the academic year.

Over a hundred UMass faculty have participated in the Innovate@ Symposium. Including the four most recent additions, there are now 29 Innovation Fellows in the College of Natural Sciences. Each Innovate Fellow has an innovation page where they discuss their proposed instructional innovations, upload videos of presentations to the Symposium participants, or highlight recent accomplishments.

Austin Rohlfing, Math Undergrad, wins Grinspoon Award

Austin Rohlfing was presented with a Grinspoon Entrepreneurial Spirit Award on 25 April. Austin’s startup, TernBooking, has combined travel accommodations with savings and budgeting for a trip. TernBooking has competed in four rounds of Berthiaume Center’s Innovation Challenge and currently maintains work space in the Berthiaume incubator. The venture will also participate in Berthiaume’s 2018 Summer Accelerator program.

Kudos to our three SCUDEM teams

On Saturday 21 April, three teams from UMass Amherst presented their work for the Spring 2018 Student Competition Using Differential Equations Modeling (SCUDEM). Starting on 13 April, each team of three students worked together on their choice of one of three modeling scenarios. On the day of the competition, they were given an additional twist to their problem to address, before presenting their model in a 2-page executive summary as well as a 10-minute presentation.

The first team, consisting of Enya Truong, Henry Phan, and Sharath Ramkumar worked on "Modeling the Cool Kids," using graph theory and Markov Chains to explain how clusters of social interactions form and break. The second team, consisting of Fusheng Yang, Joe Shao, and Hui Kennedy worked on "Sorting Recyclables," where they modeled the separation of paper and cardboard materials with a fan. Their model included the differences in acceleration and drag on the two materials, and they were awarded "meritorious" mention. The third team, consisting of Jonah Chaban, Jimmy Hwang, and Artem Vysogorets also worked on "Sorting Recyclables." They included detailed modeling of tumbling paper along with random orientation of the paper stream, and they were awarded an "outstanding" mention (they also finished first in the Fall 2017 competition).

Assistant Professor Matthew Dobson served as the faculty coach for our three teams, and also led the morning development session for the other faculty coaches.

And in other news....

Professors Tom Braden and Rob Kusner, Visiting Assistant Professor Jacob Matherne (who's heading to the Institute for Advanced Study in Princeton next year - kudos to Jacob), and PhD candidate Andrew Havens were among attendees at the Spring AMS sectional meeting at Northeastern University. On 21 April, Tom gave a talk in the Arrangements of Hypersurfaces special session on "Equivariant cohomology and intersection cohomology of a completion of a hyperplane arrangement," while Rob spoke on "Geometry and stability of critical point-configurations in $S^2$ and critical links in $S^3$" at the Discretization in Geometry and Dynamics special session 22 April.

Vlad Emelyanov, a graduating senior in CS with a Mathematics minor, developed online assessment materials for statistics courses at UMass this semester under the supervision of VAP Eric Hall. These resources were also contributed to the Open Problem Library of WeBWorK, a nationally used open-source online homework system supported by the MAA and NSF. This curriculum development project was undertaken with a Flex Grant from the Institute for Teaching Excellence and Faculty Development at the University of Massachusetts Amherst.

Distinguished Professor Panos Kevrekidis has published his third paper in Nature Communications this academic year . In addition to To infinity and some glimpses of beyond and Direct measurement of superdiffusive energy transport in disordered granular chains, his paper Interactions and scattering of quantum vortices in a polariton fluid has just appeared. Panos's new book, co-authored with VAP Christopher Chong, on Coherent Structures in Granular Crystals: From Experiment and Modelling to Computation and Mathematical Analysis has also been published recently by Springer-Verlag.

During 2-3 April, Professor Michael Lavine served on a committee reviewing the Department of Computer Science & Statistics at the University of Rhode Island. He also delivered a talk at the New England Statistics Symposium, held at UMass on 14 April. Patrick Flaherty and Anna Liu were among the organizers of the Symposium.

Professor Ivan Mirkovic reports that "one of our faculty has been elected as a corresponding member of the Academy of Sciences in the picturesque Balkan country of Croatia" - here "corresponding" means the member lives outside the country - kudos to Ivan!

At Northeastern University on 5 April, and at Yale University on 26 April, Marshall H. Stone VAP Luca Schaffler gave seminar talks titled "Equations for point configurations to lie on a rational normal curve."

News Briefs will return in the Fall. Have a pleasant summer!

### April 2018

Visiting Assistant Professor Stathis Charalampidis gave a talk titled "Formation of rogue waves in continuum and discrete models: Theory and Computation" during the AMS Sectional Meeting at Ohio State University on Saturday 17 March.

Professor Michael Lavine attended the OSAC all-hands meeting in Chicago between 20 and 23 March as a member of the fingerprint subcommittee; OSAC is an arm of NIST. He became an Associate Editor for a special issue of The American Statistician on statistical inference in the 21st century, and had a paper "Frequentist, Bayes, or Other?" accepted for publication there.

In a research seminar at MSRI on 7 March, Associate Professor Alexei Oblomkov presented his joint work with Andrei Okounkov and Rahul Pandharipande. He is a Research Professor at MSRI for the Spring semester as a part of its Enumerative Geometry Beyond Numbers program. Alexei was also named a Simons Fellow for the year 2018. (The Simons Foundation supports a one-semester extension of his sabbatical leave, and Alexei plans to visit his collaborators during the Fall semester.)

Professor Franz Pedit gave colloquium talks, at the University of Innsbruck on 9 March and at the Technical University Vienna on 15 March, titled "Gradient flows of geometric variational problems: the elastic curve flow." He also gave a plenary lecture of the same title at the workshop Geometry of Submanifolds and Integrable Systems organized by the International Research Network Project “Symmetry, Topology and Moduli” at the Osaka City Advanced Mathematical Institute during 23-30 March. After that, Franz embarked for Beijing to spend 3 months in the Yau International Mathematical Institute at Tsinghua University.

On 9 March, Professor HongKun Zhang gave both a colloquium talk on "Various diffusion behavior of Lorentz gases" and a Dynamical Seminar talk on "Markov partitions for hyperbolic systems with singularities" at the Mathematics Department of Indiana University–Purdue University, Indianapolis. Between 18-23 March, HongKun attended the conference New Developments in Open Dynamical Systems and Their Applications at Banff, Canada, of which she was one of the main organizers. The conference, supported by the Banff International Research Station for Mathematical Innovation and Discovery (BIRS), brought together more than 40 participants from around the world, including many leading experts in the field of dynamics related to open systems. Diverse branches of research in this field have applications ranging from quantifying the occurrence of rare events, such as large storms or financial crises, to understanding the fundamentals of thermodynamics. By studying connections between these various types of open systems, the conference promoted progress and fostered new directions of research in this rapidly developing area of dynamics.

!!! Newsflash !!!

Kudos to our three SCUDEM teams!!!

On Saturday 21 April, three teams from UMass Amherst presented their work for the Spring 2018 Student Competition Using Differential Equations Modeling (SCUDEM). Starting on 13 April, each team of three students worked together on their choice of one of three modeling scenarios. On the day of the competition, they were given an additional twist to their problem to address, before presenting their model in a 2-page executive summary as well as a 10-minute presentation.

The first team, consisting of Enya Truong, Henry Phan, and Sharath Ramkumar worked on "Modeling the Cool Kids," using graph theory and Markov Chains to explain how clusters of social interactions form and break. The second team, consisting of Fusheng Yang, Joe Shao, and Hui Kennedy worked on "Sorting Recyclables," where they modeled the separation of paper and cardboard materials with a fan. Their model included the differences in acceleration and drag on the two materials, and they were awarded "meritorious" mention. The third team, consisting of Jonah Chaban, Jimmy Hwang, and Artem Vysogorets also worked on "Sorting Recyclables." They included detailed modeling of tumbling paper along with random orientation of the paper stream, and they were awarded an "outstanding" mention (they also finished first in the Fall 2017 competition).

Assistant Professor Matthew Dobson served as the faculty coach for our three teams, and also led the morning development session for the other faculty coaches.

### March 2018

On 21 February, Visiting Assistant Professor Jeremiah Birrell spoke in the Mathematical Physics and Probability Seminar at the University of Arizona; his talk was titled "Small Mass Limit of Noisy Inertial Particle Dynamics: Homogenization, Instantaneous Equilibration, and Entropy Production."

The 2017 William Lowell Putnam exam results are in: out of 575 participating institutions in the US and Canada, UMass Amherst ranked 46th, an excellent result! (Last year we ranked 55th out of 568.) Our three team members were Alexander Fischer, James Hagborg and Artem Vysogorets. James did particularly well, placing in the top 7% of the 4638 students taking the Putnam last December; Patrick Lei also had a noteworthy individual performance. Many thanks to VAP Liubomir Chiriac for his fine job running the Putnam seminar last fall.

Assistant Professor Nestor Guillen is applying his professional expertise to the topic of Gerrymandering. On 4 February he spoke at the Austin Gerrymandering Workshop, with a presentation about optimal transport and calculus of variations perspectives on redistricting. Nestor was also a part of the “Gerrymandering Steals Elections: Learn How It’s Done and How to Stop It" panel in Northampton on 12 February; moderated by former mayor Clare Higgins, other panelists were U. S. Representative Jim McGovern, State Representative Paul Mark, and Adam Hilton of Mount Holyoke College.

Assistant Professor Alejandro Morales gave the colloquium at the Tulane University math department on 29 February (OK, 1 March). His topic was "Volume and lattice point formulas for flow polytopes."

### February 2018

The Department welcomes Professor Nathaniel Whitaker as our new Head! Nate succeeds Farshid Hajir, who was appointed late last summer as the UMass Senior Vice Provost for Academic Affairs.

Visiting Assistant Professor Eric Hall gave an invited talk about “Robust information divergences for model-form uncertainty arising from sparse data in random PDE” at the Center for Nonlinear Studies at Los Alamos National Lab on 9 January. In other news, VAP Hall has been awarded an Early Career Travel Grant from the American Mathematical Society to attend the 2018 ICM.

Professor Rob Kusner was invited to China for the first 3 weeks of January to work on the geometry of minimal surfaces in spheres with former UMass research fellow Wang Peng. On Friday the fifth, Kusner delivered a pair of lectures titled "Complex Polynomials Classifying Coplanar CMC Surfaces" at Tongji University in Shanghai; the following weekend he lectured on the same topic at a conference in Xiamen organized by Guan Bo, a former UMass Ph. D. student and postdoctoral visitor, now a professor at both Ohio State University and also Xiamen University. (Rob reports: the food was good, the math was great, and the fast intercity trains were simply amazing! :-)

At the beginning of January, a video on Alcuin numbers of graphs featuring Assistant Professor Annie Raymond was published on the Numberphile channel on YouTube.

### December 2017

On 7 December, the New York Times reported on a list of books banned by the Texas Department of Criminal Justice. The list includes novels by Dave Barry, Alice Walker, and Carl Hiassen; a 1908 Sears, Roebuck catalogue; and a popup version of A Charlie Brown Christmas. The 10,000 banned titles, compiled by staff in prison mailrooms, also includes Merriam-Webster’s Guide to Everyday Math, written by Senior Lecturer Brian Burrell. Choices were made on the basis of "graphic sexual content" – not a problem in this instance – or "material that could help inmates make a weapon, plot an escape, or stir disorder." Surprisingly, no other math books have been banned. Nor were American Psycho or Mein Kampf on the list. Whether it is a greater honor to be on the banned list or on the approved list is not clear. Burrell is happy simply to have been included on either one.

On 16 November, Professor Erin Conlon gave the Department of Mathematics and Statistics seminar at the University of Maine; her lecture was titled "Parallel Markov Chain Monte Carlo Methods for Bayesian Analysis of Big Data."

Professor Paul Hacking has been invited to deliver a lecture at the 2018 International Congress of Mathematicians (ICM) to be held on 1-9 August 2018 in Rio de Janeiro, Brazil. He will speak in the section on Algebraic and Complex Geometry, together with his collaborator Sean Keel from the University of Texas-Austin. The ICM has been held roughly every four years, starting in 1897; it is one of the premier forums for presenting and discussing significant new mathematical discoveries.

Professor Markos Katsoulakis was recently nominated to serve on the editorial board of the Society for Industrial and Applied Mathematics (SIAM) Journal of Uncertainty Quantification . While SIAM has an enviable reputation for producing high quality publications across the full range of applied mathematics, this journal holds a special place in the SIAM line-up. Established in 2013 as a joint venture with the American Statistical Association, the SIAM Journal of Uncertainty Quantification is well-positioned in an era when links between applied mathematics and statistics are of growing importance. Markos has also been an editor of the SIAM journal Math Analysis.

At Penn's Minimal Surfaces Seminar on 21 November, Professor Rob Kusner talked about the "Morse index and Willmore stability of minimal surfaces in spheres."

Professor Franz Pedit gave a talk titled "Conformal flows minimizing the elastic (Willmore) energy for curves and surfaces" at the Oberseminar of the Leibnitz University Hannover on 8 November.

News Briefs will resume in the spring semester. Have a wonderful winter solstice and a perfectly pleasant perihelion!