English

Bielliptic quotient modular curves of $X_0(N)$

Number Theory 2023-01-03 v1 Algebraic Geometry

Abstract

Let N1N\geq 1 be a non-square free integer and let WNW_N be a non-trivial subgroup of the group of the Atkin-Lehner involutions of X0(N)X_0(N) such that the modular curve X0(N)/WNX_0(N)/W_N has genus at least two. We determine all pairs (N,WN)(N,W_N) such that X0(N)/WNX_0(N)/W_N is a bielliptic curve and the pairs (N,WN)(N,W_N) such that X0(N)/WNX_0(N)/W_N has an infinite number of quadratic points over Q\mathbb{Q}.

Keywords

Cite

@article{arxiv.2208.10957,
  title  = {Bielliptic quotient modular curves of $X_0(N)$},
  author = {Francesc Bars and Mohamed Kamel and Andreas Schweizer},
  journal= {arXiv preprint arXiv:2208.10957},
  year   = {2023}
}

Comments

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