In the summer of 2025, we were delighted to host a number of conferences and workshops at The Ohio State University. In May the department hosted the conference Geometry and Topology of Polyhedral Complexes: In Celebration of Mike Davis’ 75th Birthday, as well as the Arithmetic, K-theory, and Algebraic Cycles Conference and Workshop. In June the department hosted the third annual KOALA Conference and the 2025 RTG Workshop and Retreat, Arithmetic Statistics. Finally, at the end of July the department hosted the annual Young Mathematicians Conference. These events brought together mathematicians at all career stages to learn about recent developments in a variety of fields and provided numerous opportunities for networking and collaboration.
The conference Geometry and Topology of Polyhedral Complexes: In Celebration of Mike Davis’ 75th Birthday took place from May 26 to May 30, 2025, and received financial support from the National Science Foundation. This conference was held in honor of Mike Davis, Professor Emeritus of Mathematics at The Ohio State University, whose research interests lie in topology and geometric group theory. Talks were given by mathematicians from around the globe. For example, Ruth Charney (Brandeis University) spoke about “Cannon-Thurston maps for Morse boundaries”, Matthew Kahle (Ohio State) spoke about “Topology of random 2-dimensional Q-acyclic complexes”, Indira Chatterji (Université Côte d’Azur à Nice) spoke about “Nori’s question”, Rachel Skipper (University of Utah) spoke about “Finiteness properties for simple groups”, and Sam Fisher (University of Oxford) spoke about “A Novikov ring short exact sequence”.
The Arithmetic, K-theory, and Algebraic Cycles Conference and Workshop took place from May 27 to May 31, 2025, and received financial support from the Clay Mathematics Institute, the National Science Foundation, the K-Theory Foundation, and Ohio State’s Mathematical Research Institute (MRI). This conference brought together leading experts and young mathematicians working in arithmetic geometry, K-theory, and algebraic cycles to discuss recent developments in these areas. Talks were given by both senior and junior faculty, as well as postdocs from around the world. For example, Bjorn Poonen (MIT) spoke about “Tetrahedra and exponential diophantine equations”, Akhil Mathew (University of Chicago) spoke about “Hyperdescent and étale K-theory”, Anand Sawant (Tata Institute of Fundamental Research, Mumbai) spoke about “Cellular A1-homology”, Evangelia Gazaki (University of Virginia) spoke about “Zero-cycles on smooth surfaces over p-adic fields”, and James Hotchkiss (Columbia University) spoke about “The topological period-index conjecture”.
The KOALA Conference took place on June 5 and 6, 2025, and received financial support from the National Science Foundation and Ohio State’s MRI. The KOALA Conference is part of the Kentucky-Ohio-ALgebraic-Alliance between the math departments of The Ohio State University and the University of Kentucky, each of which has a number of faculty, postdocs, and graduate students working in combinatorial algebraic geometry. This was the third meeting of the KOALA Conference, which alternates annually between Ohio State and the University of Kentucky and has several goals: survey recent developments in combinatorial algebraic geometry, expose graduate students and young researchers to problems and tools used in combinatorial algebraic geometry, and establish a community of mathematicians in Kentucky and Ohio working in this research area. This conference featured talks given by Richard Haburcak (Ohio State) on “Limit linear series, theta characteristics, and reducible Brill-Noether loci”, Matt Larson (Princeton) on “Complementary vectors of level complexes”, Stephen McKean (BYU) on “Punctual Hilbert schemes and higher partitions”, and Vasu Tewari (University of Toronto Mississauga) on “Equivariant quasisymmetric and noncrossing partitions”.
The RTG 2025 Workshop on Arithmetic Statistics took place from June 17 to June 20, 2025, and received financial support from the National Science Foundation and Ohio State’s MRI. This workshop consisted of two mini courses (of four lectures each) given by Alexander Smith (Northwestern University) on “BSD implies Goldfield” and by Jiuya Wang (University of Georgia) on “Malle’s Conjecture and Cohen-Lenstra Heuristics”. Each lecture was preceded by a pre-talk given by either a graduate student or postdoctoral participant. The workshop was followed by a group retreat from June 23 to June 26, 2025, held at the Burr Oak Lodge and Conference Center, to allow opportunities for intensive mathematical collaboration and community building.
Finally, the Young Mathematicians Conference took place from July 30 to August 1, 2025, and received financial support from the National Science Foundation, Ohio State’s MRI, and private donations. The Young Mathematicians Conference (YMC) has taken place nearly every summer since 2003 and provides an opportunity for undergraduate students to present their own research, attend panels on graduate school, network with peers and potential faculty research mentors, and attend plenary talks given by highly accomplished researchers and educators. This year’s plenary talks were given by Pamela E. Harris (University of Wisconsin at Milwaukee) on “Kostant’s partition function and magic multiplex juggling sequences”, Ryan Hynd (University of Pennsylvania) on “Mean Field Games”, and Cary Malkiewich (Binghamton University) on “Scissors congruence, old and new”. There were over thirty talks given by undergraduates at this summer’s YMC, covering a range of topics, including “Magic Squares of Squares”, “Using Gowers Norms in Improving Signal Recovery Conditions”, “Matrix Product Operators for Honeycomb Matchings”, “The Ordered Zeckendorf Game”, and “Optimal Reinsurance under Utility-Based Preferences Risk Sharing”.
Article contributed by Connor Cassady