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arXiv · 2407.17680

Watkins's conjecture for elliptic curves with a rational torsion

Subham Bhakta·Srilakshmi Krishnamoorthy
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Abstract

Watkins's conjecture suggests that for an elliptic curve $E/\mathbb{Q}$, the rank of the group $E(\mathbb{Q})$ of rational points is bounded above by $\nu_2 (m_E)$, where $m_E$ is the modular degree associated with $E$. It is known that Watkins's conjecture holds on average. This article investigates the conjecture over certain thin families of elliptic curves. For example, for prime $\ell$, we quantify the elliptic curves featuring a rational $\ell$-torsion that satisfies Watkins's conjecture. Additionally, the study extends to a broader context, investigating the inequality $\mathrm{rank}(E(\mathbb{Q}))+M\leq \nu_2(m_E)$ for any positive integer $M$.

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Subham Bhakta, Srilakshmi Krishnamoorthy. 2024-07-25. Watkins's conjecture for elliptic curves with a rational torsion. https://arxiv.org/abs/2407.17680

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