OAI/LinearAlgebra/CirculantHadamard/CyclotomicAwayLocal.lean

GitHub source file

14 declarations, 0 contain sorry, 0 declared as axioms

The actual away coefficient localization

The prime ideal is the contraction of a maximal ideal of the actual global root ring. Its maximality follows from integrality of the coefficient inclusion, and the single-generator theorem identifies its localization with the unramified cyclotomic construction.

  1. abbrev OAI.CirculantHadamard.CyclotomicAwayLocal.awayPrime line 25

    Source documentation

    The actual prime ideal on the coefficient ring with one direction omitted.

    abbrev awayPrime (u p : ℕ) (m : Ideal (B u)) : Ideal (awayRing u p) :=
    …
  2. abbrev OAI.CirculantHadamard.CyclotomicAwayLocal.AwayLocal line 29

    Source documentation

    The coefficient localization used in the prime-direction comparison.

    abbrev AwayLocal (u p : ℕ) (m : Ideal (B u)) [m.IsPrime] :=
    …
  3. instance OAI.CirculantHadamard.CyclotomicAwayLocal.awayLocal_algebra line 32
  4. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.awayInclusion_isIntegral line 39

    Source documentation

    Integrality follows from the genuine finite integer module structure of the global root ring, through the coefficient inclusion.

    theorem awayInclusion_isIntegral (u p : ℕ) :
        (awayInclusion u p).toRingHom.IsIntegral := by
    …
  5. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.awayMaximal line 47
  6. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.natCast_mem_comap_of_mem line 52
  7. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.prime_mem_awayPrime line 58
  8. instance OAI.CirculantHadamard.CyclotomicAwayLocal.awayLocal_charZero line 62
  9. instance OAI.CirculantHadamard.CyclotomicAwayLocal.awayLocal_noetherian line 68
  10. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.maximalIdeal_eq_span_of_eq line 73
  11. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.awayLocal_maximalIdeal_eq_span line 83

    Source documentation

    The maximal ideal of the exact contracted localization is generated by the rational prime; no ring-property premise is assumed.

    theorem awayLocal_maximalIdeal_eq_span (u p : ℕ) (hu : Odd u)
        (hp : p ∈ u.primeFactors) (m : Ideal (B u)) [m.IsMaximal]
        (hpm : (p : B u) ∈ m) :
        maximalIdeal (AwayLocal u p m) = Ideal.span {(p : AwayLocal u p m)} := by
    …

    Mentions: OAI.CirculantHadamard.CyclotomicAwayLocal.AwayLocal

  12. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.awayLocal_prime_ne_zero line 93
  13. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.awayLocal_prime_not_isUnit line 97
  14. theorem OAI.CirculantHadamard.CyclotomicAwayLocal.awayLocal_isDiscreteValuationRing line 103