Rational torsion points on Jacobians of Shimura curves

Hwajong Yoo

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arXiv · 1502.07370

Rational torsion points on Jacobians of Shimura curves

Hwajong Yoo

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Abstract

Let $p$ and $q$ be distinct primes. Consider the Shimura curve $\mathcal{X}$ associated to the indefinite quaternion algebra of discriminant $pq$ over $\mathbb{Q}$. Let $J$ be the Jacobian variety of $\mathcal{X}$, which is an abelian variety over $\mathbb{Q}$. For an odd prime $\ell$, we provide sufficient conditions for the non-existence of rational points of order $\ell$ on $J$. As an application, we find some non-trivial subgroups of the kernel of an isogeny from the new quotient of $J_0(pq)$ to $J$.

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Hwajong Yoo. 2015-02-25. Rational torsion points on Jacobians of Shimura curves. https://arxiv.org/abs/1502.07370

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