Quadratic points on dynamical modular curves

John R. Doyle; David Krumm

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arXiv · 2301.00510

Quadratic points on dynamical modular curves

John R. Doyle·David Krumm

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Abstract

Among all the dynamical modular curves associated to quadratic polynomial maps, we determine which curves have infinitely many quadratic points. This yields a classification statement on preperiodic points for quadratic polynomials over quadratic fields, extending previous work of Poonen, Faber, and the authors.

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John R. Doyle, David Krumm. 2023-01-02. Quadratic points on dynamical modular curves. https://arxiv.org/abs/2301.00510

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