Computing endomorphism rings and Frobenius matrices of Drinfeld modules

2019/08/05 by Sumita Garai, Garai, Sumita, Mihran Papikian +1
Computer Science · Mathematics · #11G09 #11R58 #Algebraic Geometry and Number Theory #Coding theory and cryptography #FOS: Mathematics #Finite Group Theory Research #Number Theory (math.NT)

paper · pdf · doi:10.48550/arxiv.1908.01805

openalex publication_date 2019/08/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Let \mathbbF_q[T] be the polynomial ring over a finite field \mathbbF_q. We study the endomorphism rings of Drinfeld \mathbbF_q[T]-modules of arbitrary rank over finite fields. We compare the endomorphism rings to their subrings generated by the Frobenius endomorphism and deduce from this a refinement of a reciprocity law for division fields of Drinfeld modules proved in our earlier paper. We then use these results to give an efficient algorithm for computing the endomorphism rings and discuss some interesting examples produced by our algorithm.

Citations

• Good Reduction of Abelian Varieties

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