Let $C$ be a smooth, projective, geometrically integral hyperelliptic curve of genus $g \geq 2$ over a number field $k$. To study the distribution of degree $d$ points on $C$, we introduce the notion of $\mathbb{P}^1$- and AV-parameterized points, which arise from natural geometric constructions. These provide a framework for classifying density degree sets, an important invariant of a curve that records the degrees $d$ for which the set of degree $d$ points on $C$ is Zariski dense. Zariski density has two geometric sources: If $C$ is a degree $d$ cover of $\mathbb{P}^1$ or an elliptic curve $E$ of positive rank, then pulling back rational points on $\mathbb{P}^1$ or $E$ give an infinite family of degree $d$ points on $C$. Building on this perspective, we give a classification of the possible density degree sets of hyperelliptic curves.
If E and E' are elliptic curves defined over a finite field k such that E(k) and E'(k) have the same order, what is the likelihood that they define isomorphic groups? In this talk we will address this question from two points of view: fix E, vary p, and fix p, vary E. This is recent and ongoing work with Nathan Kaplan of UC Irvine.
Hecke algebras play a central role in both number theory and representation theory. While some Hecke algebras have explicit descriptions in terms of generators and relations, others are understood through structure constants that encode multiplicities in tensor products of representations. In this talk, I will discuss several projects with Thibaud van den Hove and Jakob Scholbach aimed at using geometry and motives to give a uniform categorification of Hecke algebras. Along the way, we will encounter the geometric Satake equivalence, Gaitsgory's central functor, and Iwahori-Whittaker models.
One of the central problems in Arithmetic Statistics is counting number field extensions of a fixed degree with a given Galois group, parameterized by discriminants. We will focus on C2≀H extensions over an arbitrary base field. While Jürgen Klüners has established the main term in this setting, we present an alternative approach that provides improved power-saving error terms for the counting function.
The Mondrian Puzzle asks whether it is ever possible to partition a square into at least two disjoint rectangles of integer side lengths and the same area where no two rectangles have the same dimension. In this talk, we show that for a positive proportion of squares, this task is impossible. Along the way, we discuss several classic results in analytic number theory.
The Bateman--Horn Conjecture predicts how often an irreducible polynomial assumes prime values. We will discuss how with sufficient averaging in the coefficients of the polynomial (exponential in the size of the inputs), one can not only prove Bateman--Horn results on average but also pin down precise information about the distribution of prime values at finite but growing scales. We will prove that 100% of polynomials satisfy the appropriate analogue of the Poisson Tail Conjecture, in the sense that the distribution of the gaps between consecutive prime values around the average spacing is Poisson.
We will also study the frequencies of sign patterns of the Liouville function evaluated at the consecutive outputs of f; viewing f as a random variable, we establish the limiting distribution for every sign pattern.
A key input behind all of our arguments is Leng's recent quantitative work on the higher-order Fourier uniformity of the von Mangoldt and M\"obius functions (in turn relying on Leng, Sah, and Sawhney's quantitative inverse theorem for the Gowers norms).
This talk is based on joint work with Noah Kravitz and Max Xu.
In this talk, we will provide a study on effective versions of the celebrated Bilu’s equidistribution theorem for Galois orbits of sequences of points of small height in the N-dimensional algebraic torus, identifying the qualitative dependence of the convergence in terms of the regularity of the test functions considered. We develop a general Fourier analysis framework that extends previous results. This is joint work with Emanuel Carneiro.
Solutions to many problems in number theory can be described using the theory of algebraic stacks. In this talk, I will describe a Diophantine equation, the so-called “generalized Fermat equation”, whose integer solutions correspond to points on an appropriate stacky curve: a curve with extra automorphisms at prescribed points. Using étale descent over such a curve, we characterize local and global solutions to a family of such equations and give asymptotics for the local-global principle in the corresponding family of stacky curves. This is joint work with Juanita Duque-Rosero, Chris Keyes, Manami Roy, Soumya Sankar and Yidi Wang.
(Joint with Ruofan Jiang and Alexei Oblomkov) The Hilbert scheme of points on planar singularities is an object with rich connections (q,t-Catalan numbers, HOMFLY polynomials, Oblomkov–Rasmussen–Shende conjecture). The Quot scheme of points is a higher rank generalization of the Hilbert scheme of points. As our main result, we prove that for the "torus knot singularity" $x^a = y^b$ with $\gcd(a,b)=1$, the Quot scheme admits a cell decomposition: every Birula-Białynicki stratum is “as nice as possible” despite poor global geometry. The proof uses two key properties of the rectangular‑grid poset: an Ext‑vanishing for certain quiver representations and a structural result on the poset flag variety. Time permitting, I will discuss a conjectured Rogers–Ramanujan type identity, whose sum side is a summation on (nested) $a \times b$ Dyck paths and product side has modulus $a+b$.