Formalized Class Group Computations and Integral Points on Mordell Elliptic Curves

Anne Baanen*, Alex J. Best, Nirvana Coppola, Sander R. Dahmen

*Corresponding author for this work

Research output: Chapter in Book / Report / Conference proceedingConference contributionAcademicpeer-review

Abstract

Diophantine equations are a popular and active area of research in number theory. In this paper we consider Mordell equations, which are of the form y2=x3+d, where d is a (given) nonzero integer number and all solutions in integers x and y have to be determined. One non-elementary approach for this problem is the resolution via descent and class groups. Along these lines we formalized in Lean 3 the resolution of Mordell equations for several instances of d<0. In order to achieve this, we needed to formalize several other theories from number theory that are interesting on their own as well, such as ideal norms, quadratic fields and rings, and explicit computations of the class number. Moreover, we introduced new computational tactics in order to carry out efficiently computations in quadratic rings and beyond.

Original languageEnglish
Title of host publicationCPP 2023
Subtitle of host publicationProceedings of the 12th ACM SIGPLAN International Conference on Certified Programs and Proofs
EditorsRobbert Krebbers, Dmitriy Traytel, Brigitte Pientka, Steve Zdancewic
PublisherAssociation for Computing Machinery, Inc
Pages47-62
Number of pages16
ISBN (Electronic)9798400700262
DOIs
Publication statusPublished - Jan 2023
Event12th ACM SIGPLAN International Conference on Certified Programs and Proofs, CPP 2023 - Co-located with POPL 2023 - Boston, United States
Duration: 16 Jan 202317 Jan 2023

Conference

Conference12th ACM SIGPLAN International Conference on Certified Programs and Proofs, CPP 2023 - Co-located with POPL 2023
Country/TerritoryUnited States
CityBoston
Period16/01/2317/01/23

Bibliographical note

Funding Information:
Anne Baanen was funded by NWO Vidi grant No. 016.Vidi. 189.037, Lean Forward. Alex J. Best, Nirvana Coppola, and Sander R. Dahmen were funded by NWO Vidi grant No. 639.032.613, New Diophantine Directions.

Publisher Copyright:
© 2023 Owner/Author.

Keywords

  • algebraic number the- ory
  • Diophantine equations
  • formalized mathematics
  • Lean
  • Mathlib
  • tactics

Fingerprint

Dive into the research topics of 'Formalized Class Group Computations and Integral Points on Mordell Elliptic Curves'. Together they form a unique fingerprint.

Cite this