Chair's Column

Dear Members and Friends of the UNT Math Department,

The past academic year started out with a big and unexpected change, when longtime faculty member Su Gao, Regents Professor and Dean of the College of Science, announced his resignation as dean, and in fact shortly thereafter his resignation from the University, for personal reasons. Su has shaped the department like none other in the recent past, being chair from 2011 to 2017 and then founding dean of the College of Science. Of course, he is also a first-rate mathematician. While a serious loss for the department, we will stay in touch and wish Su all the best in his new position at Nankai University.

The new Dean of COS became Pamela Padilla, Professor of Biological Sciences, who was just as supportive of the department. We received summer stipends for graduate students, generous funding for future renovations, and even new faculty positions when opportunities arose. We truly appreciate the college's continued support.

Fall 2021 saw the transition back to face-to-face instruction, which by all indications was welcomed as a relief for both faculty and students. The number of student complaints plummeted compared to the year before, not only a testament to the abilities of our instructors, but also to the overall reduced stress level. I have however had reports from instructors in some classes that damage had been done in over a year of online instruction: students are just not at the same level which they used to be.

As for new colleagues, we welcomed Assistant Professor Kirill Lazebnik, who is reinforcing our Dynamical Systems group. Not new to the department, but in a new role as Associate Professor, is Nirmala Naresh, an expert in Math Education who will lead an effort to develop a Master's program in this area. With special funding we were able to recruit a Visiting Lecturer, Lauren De La Rosa, who helped us teach the much increased number of students deemed not college ready; Lauren will in fact become a continuing lecturer next year. As part of the built-up of our postdoc program, we welcomed Jonathan Cohen, a Visiting Assistant Professor who is working closely with myself. In January we welcomed an additional VAP, Dominik Adolf, who is working under the mentorship of Assistant Professor Nam Trang. We also suffered two resignations, lecturer Jason Taylor and Instructional Lab Supervisor Heidee Vincent.

In an all-hands-on-deck situation, the past spring semester was marked by a considerable amount of hiring. We managed to fill three tenure-track positions, two in Algebra and one in Applied PDE. We were also able to hire three new lecturers, one of whom will be teaching math classes in Frisco. Furthermore, three new postdocs will join us in the fall. The Instructional Lab Supervisor position is expected to be filled by that time as well. I am quite excited about welcoming the new colleagues, and would like to thank the various search committees for their excellent work.

As a visible sign of modernization, we now have two large display monitors outside the main office (essentially paid for by repurposed faculty travel funds which had been left unused during Covid times). It took a long time from order to installation, because of supply chain issues. It took several more weeks and help from CAS-IT to connect the monitors to the local network. Finally, there was a somewhat steep learning curve with the required software, but it was all worth the effort. One monitor is cycling through the picture boards, which we will never have to order in cardboard format again. The other monitor shows various announcements and also pieces of math humor, which seem to be widely appreciated.

Other changes small and large are happening, be it tweaks to existing courses, career initiatives, new online offerings, discussions about graduate program reform, new leadership roles in the department, IDEA events, or "invisible" procedural changes to increase efficiency. I am optimistic the department is evolving towards a bright future.

Ralf Schmidt
Chair

Professor Mariusz Urbański publishes a new book

Professor Mariusz Urbański in collaboration with Mario Roy and Sara Munday have published the first volume of a series of books entitled “Non-Invertible Dynamical Systems”. These books are aimed at researchers, graduate and postgraduate students on dynamical systems and ergodic theory. Professor Urbański received his Ph.D. from Nicolaus Copernicus University (Uniwersytet Mikołaja Kopernika) in Toruń, Poland in 1985. He is among the top 2% of the most-cited mathematicians and his research interests are extensive and include fields such as dynamical systems, ergodic theory, fractal geometry, conformal dynamical systems, holomorphic dynamical systems, open dynamical systems, iteration of transcendental meromorphic functions, iterated function systems, thermodynamic formalism, gas lattices, statistical physics, potential theory (harmonic measure), number theory, Kleinian groups, and topology (topological dimension).

This first volume “Ergodic Theory – Finite and Infinite, Thermodynamic Formalism, Symbolic Dynamics and Distance Expanding Maps” contains a detailed treatment of thermodynamic formalism on general compact metrizable space. Besides many other topics, topological pressure, topological entropy, variational principle, and equilibrium states are presented in detail. Also, a fairly full account of the classical theory of Shub’s expanding endomorphisms is given which prior to this book did not have a book presentation in English language mathematical literature.

Jana Watkins receives the 2022 UNT Star Performer award

The Department of Mathematics wants to celebrate Jana Watkins for receiving the 2022 UNT Star Performer Award. This honor is in acknowledgement of the exceptional contributions that staff members have made by assisting the University in meeting its strategic goals, while demonstrating its core values. Jana Watkins has been the administrative coordinator for the Mathematics Department since July 2011. In this role she has a quite long list of duties such as supervising and leading the staff, serving as assistant to the chair, managing department budgets, travel and grant support etc. Last year, she also took on a significant amount of additional duties, and got up to speed on these new responsibilities in no time. Besides the quantity, the quality of all of Jana’s work is also quite impressive. She is very good keeping up to date with policy changes, attending trainings for new business processes, and communicating with administrative staff across campus to make sure things are running smoothly. Through the years, Jana has acquired an enormous amount of knowledge that is invaluable to the operation of the department. The department chair summarized her approach to work as “helpfulness and service through competence.” In addition, Jana’s leadership style has created an amazing work environment in the main office, allowing all the staff to thrive and in fact enjoy their work, ultimately benefiting the entire department and beyond.

Texas Section of the MAA Conference

On March 31-April 2, the Texas Section of the MAA Conference was held at the UNT Gateway Center. There were about 225 attendees from multiple schools in Texas including (in no particular order) Tarleton State University, Hardin-Simmons University, Stephen F. Austin State University, Tyler Junior College, Southwestern University, University of Mary Hardin-Baylor, Texas A&M-Commerce, Sul Ross State University, University of Texas-Arlington, Midwestern University, Austin College, Collin College, Wayland Baptist University, Laredo College, Texas Lutheran University, Angelo State University, University of Dallas, St Edward’s University, Texas Christian University, Lone Star College, Texas State University, Abilene Christian University, Texas Tech University, LeTourneau University, Baylor University, and Bishop Lynch High School in Dallas. We had some great talks by Robert Vallin, Raegan Higgins, Adriana Salerno, and Colin Adams. We also had a Math Bowl, a panel discussion, 12 minute undergraduate and faculty talks, a banquet, and a great banquet address by John Quintanilla. There are some photos from the Math Bowl and Banquet on the website for the conference. Next year’s conference will be at Tarleton State University in Stephenville, Texas.

New Faculty Members

Kirill Lazebnik

Kirill Lazebnik joined the department in Spring 2022 as an Assistant Professor. He previously worked as a Brauer Postdoctoral Fellow at the University of Toronto, and as a Harry Bateman Research Instructor at the California Institute of Technology. He received his Ph.D. in 2017 from Stony Brook University. His research is mainly in the field of complex dynamics. This is the study of the iteration of complex-analytic functions, and traditionally arose from studying the effectiveness of root-finding algorithms and the geometry of fractal objects. His professional goal is to contribute to the understanding of his field, and to engage with the UNT student community.

Dominik Adolf

Dominik Adolf joined the department in Spring 2022 as a Visiting Assistant Professor. He earned BS and PhD degrees from the WWU Münster. Before coming to UNT he held various positions at several mathematical institutions. He works in set theory, mainly in inner model theory, but he has dabbled into forcing. He is mainly interested in properties of singular cardinals; these are like the pillars of the mathematical universe and so a lot of the most interesting research happens around or on these cardinals.

Jonathan Cohen

Jonathan Cohen joined the department in Fall 2021 as a Visiting Assistant Professor. He earned BS and PhD degrees from the University of Maryland. Before coming to UNT he was a Postdoctoral Researcher at the University of Oklahoma. His research interests lie at the intersection of number theory and representation theory. Jonathan studies various aspects of complex representations of p-adic reductive groups as a component of the modern theory of automorphic forms and with applications to the Langlands Program.

Donation from former faculty member Joseph Kung

The Department of Mathematics received a generous gift of $1,000 from former faculty member Joseph Kung. The amount of this kind donation has been added to the Mauldin Scholarship. Joseph joined the University of North Texas and was a faculty member until his retirement as Professor Emeritus in 2017. Throughout his career, Joseph made nu­merous contributions to mathematics and to the mathematical community.

Grants

Several faculty members were awarded grants this year:

• Yanyan He was awarded two grants, one sponsored by the National Science Foundation and another one sponsored by the Army Research Office titled "Collaborative Research: Using uncertainty quantification and validated computational models to analyze pumping performance of valveless, tubular hearts" and "Using uncertainty quantification and machine learning techniques to study the evolution of odor capture", respectively.
• Joseph Iaia was awarded a CURM (Center for Undergraduate Research in Mathematic) grant to work with with two undergraduates on research in differential equations. The students will attend at least two conferences and will present their results at the 2023 Texas Section Meeting of the MAA at Tarleton State University.
• Mariusz Urbański was named a Simons Fellow: this program provides funds to faculty for up to a semester-long research leave from classroom teaching and administrative obligations.

Promotions

Pieter Allaart

The UNT Provost has recommended Dr. Pieter Allaart for promotion to full professor. Dr. Allaart’s research interests lie in optimal stopping, probability inequalities, fractal geometry, nondifferentiable functions, and Beta expansions. He has published 48 peer-reviewed articles, and successfully supervised 4 Ph.D. students and 3 M.S. students. He currently holds a Simons Foundation Collaborations Grant for Mathematicians. In 2009 he was appointed the prestigious position of GCOE (Global Centers of Excellence) Foreign Researcher at Kyoto University, and in 2021 he received the UNT Department of Mathematics Faculty Research Award. He began his employment at UNT as a Visiting Assistant Professor in 1998, became an Assistant Professor in 2001, and was promoted to Associate Professor in 2007. He completed his Ph.D in 1998 at the Free University Amsterdam shortly before coming to UNT.

Allen Mann

The UNT Provost has recommended Dr. Allen Mann for promotion to Principal Lecturer. Dr. Mann has taught courses across the mathematics curriculum, focusing in particular on Elementary Probability and Statistics, Applied Statistics, and courses for first-year TAMS students. He currently serves as a course coordinator for Elementary Probability and Statistics and as the liaison between TAMS and the Department of Mathematics. He has received the UNT Excellence in Undergraduate Teaching Award from TAMS and the Honors College as well as a Faculty Service Award from the Department of Mathematics. Dr. Mann started at UNT as a Lecturer in 2015 and was promoted to Senior Lecturer in 2018. Prior to his time at UNT, he taught at several other institutions and spent time in Europe as a postdoctoral fellow after receiving his Ph.D. from the University of Colorado at Boulder. His research interests include logic, algebra, and game theory, and he has published in several research journals and presented his work at international seminars and conferences.

2022 Integration Bee

After a 2 year hiatus due to Covid, we had the 2022 Integration Bee on Friday, April 8 in GAB 105. We had 58(!) intrepid, take-no-prisoners competitors and that was just for the cake! They were even tougher when it came to indefinite integrals. We also had a fearless squad of graders and cake/soft drink servers.

The winners this year were 3 TAMS students – Brian Jiang (senior), Etash Bhat (junior), and Zachary Li (junior). (In the photo Brian is in the center, Etash on the right, and Zachary on the left).

In addition we had some trivia questions – some mathematics related and others not. Which Shakespeare character says, “I am ill at these numbers”? (Hamlet). Which famous mathematicians have birthdays in April? (Gauss, Euler). What was the big event of April 12, 1961? (Yuri Gagarin is the first to orbit the earth). Who said “Always do right. It will gratify some and astonish the rest”? (Mark Twain). And what is the theme song of the movie “Breakfast at Tiffany’s”? (Moon River).

Congratulations to all the winners and participants!

Math Club

The Math Club is devoted to promoting interest in mathematics and fellowship among students of all mathematical backgrounds. Meetings are at 1pm in GAB 473 to discuss math, play games, prepare for the Putnam exam, and to plan departmental picnics. The semester picnics take place at North Lakes Park.

Putnam Competition

The 82nd William Lowell Putnam Exam was on Saturday Dececember 4 and we had one fearless competitor this year – the intrepid Michalis Paizanis!
Michalis got a 21 on the Putnam Exam placing him between 212th place and 489th place, congratulations Michalis!
The William Lowell Putnam exam is offered every year on the first Saturday in December to undergraduates. The problems are quite challenging; getting even 1 question correct is an achievement! For the last several years in the Fall semester Dr. Allaart and Dr. Iaia have team taught Math 3010 – a one credit hour problem solving class which helps undergraduates prepare for the Putnam exam.
If you are interested in learning more about the exam, please check out the following websites: https://www.maa.org/math-competitions/putnam-competition and https://kskedlaya.org/putnam-archive/ (problems and solutions from 1985-2022).

Problem of the Month

Every month during regular semesters, the Math Department and the Math Club feature the Problem of the Month competition. This contest is open to all currently enrolled undergraduate students. Students who submit correct solutions receive cash prizes and certificates of excellence. The students who participated and submitted correct answers from September 2020 until March 2020 are: Michael Holland, Divya Darji, Eric Peng, Yugendra Uppalapati, Michalis Paizanis, James Heath, Nicolas Heredia, Atharv Chagi.

Graduate and Undergraduate Research News

• Taylor Jones was featured in the College of Science website.
• Tobey Mathis was featured in the College of Science website, in the Great Grads: Spring 2022 and he received the Science Undergraduate Research Presentation Award.
• Michalis Paizanis was awarded the Undergraduate Research Fellowship and presented his paper (with Tobey Mathis, Nathan Dalaklis and Kiko Kawamura) in the UNT Sholars Day on April 5, 2021.

Faculty Awards

• Faculty Research Award: Mariusz Urbanski
• Faculty Teaching Award: Matthew Dulock and Kai-Sheng Song
• Faculty Service Award: Krista Hines and Anne Shepler
• Outstanding Adjunct Award: Rhonda Huettenmueller

Graduate Awards and Scholarships

• Outstanding Graduate Student: Cody Olsen
• Academic Excellence Award: Alex Creiner
• Outstanding Teaching Fellow: Dillon Hanson

• John Ed Allen Scholarship: Sasha Montag
• Dan Mauldin Scholarship: Stewart Brown
• John Neuberger Scholarship: Harrison Daniels

Undergraduate Awards and Scholarships

• Outstanding Undergraduate Student: Michalis Paizanis
• Outstanding Student in Actuarial Science: Hong Tran
• Outstanding Student Math Lab Tutor: Galen Bouguyon

• David Dawson Scholarship: Violet Forbes
• E.H. Hanson Scholarship: Chi Lin
• Mildred Masters McCarty Scholarship: Rilee Harmon
• Roger L. Perry Scholarship: Chaleese Powell
• Ram Lal Seekri Scholarship: David Lee