Teams Meeting ID: 357 640 366 598 58
1pm-2pm, Tuesday, MB-503
27/1/2026: Abhiram Natarajan (Warwick)
Title: Semi-Pfaffian geometry - tools, and applications .
References: [1] Larry Guth, Polynomial partitioning for a set of varieties, Mathematical Proceedings of the Cambridge
Philosophical Society, vol. 159, Cambridge University Press, 2015, pp. 459–469.
[2] Larry Guth and Nets Hawk Katz, On the Erdős distinct distances problem in the plane, Annals of
mathematics (2015), 155–190.
3/2/2026: Federico Ardila-Mantilla (QMUL)
Title: Tree metrics and log-concavity for matroids.
Abstract: We show that a set function ν satisfies the gross substitutes property if and only if its homogeneous generating polynomial Zq,ν is a Lorentzian polynomial for all positive q≤1, answering a question of Eur-Huh. We achieve this by giving a rank 1 upper bound for the distance matrix of an ultrametric tree, refining a classical result of Graham-Pollak. This characterization enables us to resolve two open problems that strengthen Mason's log-concavity conjectures for the number of independent sets of a matroid: one posed by Giansiracusa-Rincón-Schleis-Ulirsch for valuated matroids, and two posed by Dowling in 1980 and Zhao in 1985 for ordinary matroids.
Special event: Lunch together + pub?
17/2/2026: TBD.
Title: TBD.
Abstract:TBD.
24/2/2026: Alejandro Vargas (Warwick)
Title: Arithmetic matroids and elliptic arrangements of complex multiplication type. .
Abstract:TBD.
3/3/2026: Mayo Mayo García (Warwick)(11.00-12.00); Siao Chi Mok (Cambridge)(13.00-14.00)
Title: TBD; TBD.
Abstract:TBD; TBD.
The April schedule is currently being cooked.