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arXiv · 2509.22837

Special endomorphisms of QM abelian surfaces

Andrew Phillips
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Abstract

In this paper we generalize a theorem of Kudla-Rapoport-Yang which gives a formula for the arithmetic degree of the moduli space of CM elliptic curves together with a special endomorphism of a specified degree. Our extension is to the moduli space of QM abelian surfaces with CM together with a special endomorphism of a specified QM degree.

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Andrew Phillips. 2025-09-26. Special endomorphisms of QM abelian surfaces. https://arxiv.org/abs/2509.22837

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