English

Weierstrass points on the Drinfeld modular curve $X_0(\mathfrak{p})$

Number Theory 2015-04-17 v2

Abstract

Consider the Drinfeld modular curve X0(p)X_0(\mathfrak{p}) for p\mathfrak{p} a prime ideal of Fq[T]\mathbb{F}_q[T]. It was previously known that if jj is the jj-invariant of a Weierstrass point of X0(p)X_0(\mathfrak{p}), then the reduction of jj modulo p\mathfrak{p} is a supersingular jj-invariant. In this paper we show the converse: Every supersingular jj-invariant is the reduction modulo p\mathfrak{p} of the jj-invariant of a Weierstrass point of X0(p)X_0(\mathfrak{p}).

Cite

@article{arxiv.1409.7466,
  title  = {Weierstrass points on the Drinfeld modular curve $X_0(\mathfrak{p})$},
  author = {Christelle Vincent},
  journal= {arXiv preprint arXiv:1409.7466},
  year   = {2015}
}

Comments

Main theorem has been strengthened. Mistakes in the proof of Theorems 5.7 and 6.2 have been fixed. A new section on the behavior of W(z) at the cusps has been added. Various typos corrected and clarifications made

R2 v1 2026-06-22T06:06:24.423Z