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arXiv · 2402.15362

Essential dimension of isogenies

János Kollár·Ziquan Zhuang
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Abstract

We give a lower bound for the essential dimension of isogenies of complex abelian varieties. The bound is sharp in many cases. In particular, the multiplication-by-$m$ map is incompressible for every $m\geq 2$, confirming a conjecture of Brosnan.

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János Kollár, Ziquan Zhuang. 2024-02-23. Essential dimension of isogenies. https://arxiv.org/abs/2402.15362

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