Formalizing the ring of Witt vectors

  title={Formalizing the ring of Witt vectors},
  author={J. Commelin and R. Lewis},
  journal={Proceedings of the 10th ACM SIGPLAN International Conference on Certified Programs and Proofs},
  • J. Commelin, R. Lewis
  • Published 2021
  • Computer Science, Mathematics
  • Proceedings of the 10th ACM SIGPLAN International Conference on Certified Programs and Proofs
The ring of Witt vectors W R over a base ring R is an important tool in algebraic number theory and lies at the foundations of modern p-adic Hodge theory. W R has the interesting property that it constructs a ring of characteristic 0 out of a ring of characteristic p > 1, and it can be used more specifically to construct from a finite field containing ℤ/pℤ the corresponding unramified field extension of the p-adic numbers ℚp (which is unique up to isomorphism). We formalize the notion of a Witt… Expand

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