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arXiv · 2511.08422

Explicit Families of Hyperelliptic Curves with CM Jacobians

Saeed Tafazolian·Jaap Top
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Abstract

We construct explicit families of hyperelliptic curves over $\QQ$ whose Jacobians admit complex multiplication (CM). Each curve in these families is defined by \[ v^2 = (u+2)\,\varphi_d(u), \quad d = 2^e \text{ or } d=p \geq 3 \text{ prime}, \] where $\varphi_d(x)$ is the Chebyshev polynomial of degree $d$. We prove that the Jacobians are simple and determine the associated CM-fields explicitly. Our approach exploits the interplay between Chebyshev polynomials and Galois coverings, providing concrete examples of abelian varieties with CM and explicit criteria for their construction.

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Saeed Tafazolian, Jaap Top. 2025-11-11. Explicit Families of Hyperelliptic Curves with CM Jacobians. https://arxiv.org/abs/2511.08422

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