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arXiv · 1810.13214

Singular Units and Isogenies Between CM Elliptic Curves

Yingkun Li
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Abstract

In this note, we will apply the results of Gross-Zagier, Gross-Kohnen-Zagier and their generalizations to give a short proof that the differences of singular moduli are not units. As a consequence, we obtain a result on isogenies between reductions of CM elliptic curves.

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Yingkun Li. 2021-03-13. Singular Units and Isogenies Between CM Elliptic Curves. https://arxiv.org/abs/1810.13214

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