arXiv subjects

Kate Finnerty

Publications and source records attributed to Kate Finnerty.

3 recordsLinked to original sources

arXiv2026

Rational Solids with Equal Surface Area and Volume

We classify pairs consisting of a right square pyramid and a right square prism, each having rational base side length and rational height, for which the two solids have equal surface area and equal volume. We prove that, up to scaling by a common positive rational factor, there is a unique such pair. The problem reduces to determining the rational points on a genus 2 bielliptic curve whose Jacobian has rank 2. We accomplish this using a quadratic Chabauty computation followed by the Mordell--Weil sieve. The same analysis gives an analogous classification for right circular cones and right circular cylinders.

math.NT↗

arXiv2025

The possible adelic indices for elliptic curves admitting a rational cyclic isogeny

In the 1970s, Serre proved that the adelic index of a non-CM elliptic curve over a number field is finite. More recently, Zywina conjectured the complete set of adelic indices for such curves over $\mathbb{Q}$. In this article, we prove that Zywina's conjecture is true for the family of non-CM elliptic curves over $\mathbb{Q}$ that admit a nontrivial rational cyclic isogeny. This strengthens a result of Lemos that resolved Serre's uniformity question for the same family of curves. Our proof proceeds by analyzing a collection of modular curves associated with each prime isogeny degree, using recent advances on $\ell$-adic images, isogeny-torsion graphs, and computations of models and rational points.

math.NT↗

arXiv2025

Quadratic Chabauty Experiments on Genus 2 Bielliptic Modular Curves in the LMFDB

We present results of quadratic Chabauty experiments on genus 2 bielliptic modular curves of Jacobian rank 2 that have recently been added to the LMFDB. We apply quadratic Chabauty methods over both the rationals and quadratic imaginary fields. In a number of cases, the experiments yielded algebraic irrational points among the set of mock rational points. We highlight specific notable examples, including the non-split Cartan modular curve $X^+_{ns}(15)$. Lastly, we offer a conjecture relating the level of the modular curve to the potential number fields over which points can arise.

math.NT↗