English

The Eisenstein ideal and Jacquet-Langlands isogeny over function fields

Number Theory 2015-05-27 v3 Algebraic Geometry

Abstract

Let p\frak{p} and q\frak{q} be two distinct prime ideals of Fq[T]\mathbb{F}_q[T]. We use the Eisenstein ideal of the Hecke algebra of the Drinfeld modular curve X0(pq)X_0(\frak{p}\frak{q}) to compare the rational torsion subgroup of the Jacobian J0(pq)J_0(\frak{p}\frak{q}) with its subgroup generated by the cuspidal divisors, and to produce explicit examples of Jacquet-Langlands isogenies. Our results are stronger than what is currently known about the analogues of these problems over Q\mathbb{Q}.

Keywords

Cite

@article{arxiv.1306.3632,
  title  = {The Eisenstein ideal and Jacquet-Langlands isogeny over function fields},
  author = {Mihran Papikian and Fu-Tsun Wei},
  journal= {arXiv preprint arXiv:1306.3632},
  year   = {2015}
}

Comments

71 pages. To appear in Documenta Mathematica

R2 v1 2026-06-22T00:34:26.755Z