English

Tropical split Jacobians of curves of genus 2 II

Algebraic Geometry 2025-02-11 v1 Combinatorics

Abstract

This paper is the second in a series of two papers which study the phenomenon of tropical split Jacobians. The first paper is a contemplative study, embedded in the broader context of exploring connections between the category of tropical abelian varieties (tav), TA\mathbb{T}\mathcal{A}, and the category of tropical curves, TC\mathbb{T}\mathcal{C}. Tropical split Jacobians take on different forms depending on whether we look at them in TA\mathbb{T}\mathcal{A} or TC\mathbb{T}\mathcal{C}: They appear either as 2 dimensional tavs that decompose into a product of two elliptic curves, or as a pair of optimal coverings. [11] examines both and then focuses on how optimal covers give rise to split Jacobians. This paper takes a different approach. Instead of looking at the phenomenon as a whole, we analyze its building blocks, a pair of elliptic curves together with a finite subgroup of their product, and how to reassemble them into a Jacobian.

Keywords

Cite

@article{arxiv.2502.05624,
  title  = {Tropical split Jacobians of curves of genus 2 II},
  author = {Lou-Jean Leila Cobigo},
  journal= {arXiv preprint arXiv:2502.05624},
  year   = {2025}
}