OAI/NumberTheory/Ostmann/Characters/PolynomialVariableSupport.lean

GitHub source file

9 declarations, 0 contain sorry, 0 declared as axioms

Variables absent from the arithmetic coefficient tests

Clearing ancestor denominators introduces only variables from the existing slots. In particular a compensation type omitted from those slots stays absent from every coefficient polynomial and every minor formed from them.

  1. def OAI.Ostmann.PolynomialGiantRows.UsesOnly line 18
  2. theorem OAI.Ostmann.PolynomialGiantRows.vars_mul_subset line 22
  3. theorem OAI.Ostmann.PolynomialGiantRows.vars_sub_subset line 26
  4. theorem OAI.Ostmann.PolynomialGiantRows.usesOnly_identity line 30
  5. theorem OAI.Ostmann.PolynomialGiantRows.usesOnly_reverse line 33
  6. theorem OAI.Ostmann.PolynomialGiantRows.minor_usesOnly line 48

    Source documentation

    A two-by-two minor has no variables beyond those of its four entries.

    theorem minor_usesOnly [DecidableEq σ] {a b c d : MvPolynomial σ ℤ} {S : Finset σ}
        (ha : a.vars ⊆ S) (hb : b.vars ⊆ S) (hc : c.vars ⊆ S) (hd : d.vars ⊆ S) :
        (a * d - b * c).vars ⊆ S :=
    …
  7. theorem OAI.Ostmann.PolynomialGiantRows.normalized_eq_of_agree line 56

    Source documentation

    Changing all variables outside the indicated slots leaves both normalized coefficient rows unchanged. This supplies the independence needed for the separate compensation-prime prior in the coincidence estimate.

    theorem normalized_eq_of_agree {K : Type*} [Field K]
        (T : PolynomialGiantRows σ) (S : Finset σ) (hT : T.UsesOnly S)
        (x y : σ → K) (hxy : ∀ i ∈ S, x i = y i) :
        T.normalized (MvPolynomial.eval₂Hom (Int.castRingHom K) x) =
          T.normalized (MvPolynomial.eval₂Hom (Int.castRingHom K) y) := by
    …

    Mentions: OAI.Ostmann.PolynomialGiantRows

  8. theorem OAI.Ostmann.PolynomialGiantRows.minor_degree_le line 70

    Source documentation

    Forming a rank test doubles the available coefficient degree bound.

    theorem minor_degree_le {a b c d : MvPolynomial σ ℤ} (D : ℕ)
        (ha : a.totalDegree ≤ D) (hb : b.totalDegree ≤ D)
        (hc : c.totalDegree ≤ D) (hd : d.totalDegree ≤ D) :
        (a * d - b * c).totalDegree ≤ 2 * D := by
    …
  9. theorem OAI.Ostmann.polynomialAncestorRows_usesOnly line 80