OAI/RepresentationTheory/FoulkesHowe/DiagonalCoefficient.lean

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7 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.Problem346.diagonalPolynomial line 16

    Source documentation

    The one-variable polynomial obtained by restricting a multilinear form to an affine diagonal.

    def diagonalPolynomial {a : ℕ} (T : MultilinearMap ℂ (fun _ : Fin a => E) ℂ)
        (x y : E) : Polynomial ℂ :=
    …
  2. lemma OAI.Problem346.diagonalPolynomial_eval line 21
  3. lemma OAI.Problem346.diagonalPolynomial_coeff_one line 43
  4. theorem OAI.Problem346.diagonal_linear_coefficient_zero line 57

    Source documentation

    If a multilinear form vanishes on an affine diagonal line, its linear diagonal coefficient vanishes. This statement does not require symmetry.

    theorem diagonal_linear_coefficient_zero {a : ℕ}
        (T : MultilinearMap ℂ (fun _ : Fin a => E) ℂ) (x y : E)
        (h : ∀ c : ℂ, T (fun _ => x + c • y) = 0) :
        (∑ i : Fin a, T (Function.update (fun _ => x) i y)) = 0 := by
    …
  5. lemma OAI.Problem346.symmetric_update_eq line 67

    Source documentation

    Symmetry identifies the terms of the linear diagonal coefficient.

    lemma symmetric_update_eq {a : ℕ}
        (T : MultilinearMap ℂ (fun _ : Fin a => E) ℂ)
        (hsym : ∀ (σ : Equiv.Perm (Fin a)) (v : Fin a → E),
          T (fun k => v (σ k)) = T v)
        (x y : E) (i j : Fin a) :
        T (Function.update (fun _ => x) j y) =
          T (Function.update (fun _ => x) i y) := by
    …
  6. theorem OAI.Problem346.symmetric_diagonal_mixed_zero line 90

    Source documentation

    Coefficient extraction for a symmetric multilinear form along an affine diagonal. This is the coefficient-of-c argument in the split binary form step.

    theorem symmetric_diagonal_mixed_zero {a : ℕ}
        (T : MultilinearMap ℂ (fun _ : Fin a => E) ℂ)
        (hsym : ∀ (σ : Equiv.Perm (Fin a)) (v : Fin a → E),
          T (fun k => v (σ k)) = T v)
        (x y : E) (i : Fin a)
        (h : ∀ c : ℂ, T (fun _ => x + c • y) = 0) :
        T (Function.update (fun _ => x) i y) = 0 := by
    …
  7. theorem OAI.Problem346.symmetric_diagonal_cons_zero line 110

    Source documentation

    The same coefficient extraction with the distinguished slot placed first.

    theorem symmetric_diagonal_cons_zero {r : ℕ}
        (T : MultilinearMap ℂ (fun _ : Fin (r + 1) => E) ℂ)
        (hsym : ∀ (σ : Equiv.Perm (Fin (r + 1))) (v : Fin (r + 1) → E),
          T (fun k => v (σ k)) = T v)
        (x y : E) (h : ∀ c : ℂ, T (fun _ => x + c • y) = 0) :
        T (Fin.cons y (fun _ : Fin r => x)) = 0 := by
    …