OAI/RepresentationTheory/Saxl/Polytabloid.lean

GitHub source file

14 declarations, 0 contain sorry, 0 declared as axioms

  1. lemma OAI.Saxl.finset_eq_of_signed_sum line 15

    Source comment

    A finite set is the unique maximizer of its strictly signed separator. Used below for the Ferrers equality case in the Specht submodule theorem.
    lemma finset_eq_of_signed_sum {X : Type uX} [DecidableEq X]
        (A B : Finset X) (w : X → ℤ)
        (hp : ∀ x ∈ B, 0 < w x) (hn : ∀ x ∉ B, w x < 0)
        (he : ∑ x ∈ A, w x = ∑ x ∈ B, w x) : A = B := by
    …
  2. lemma OAI.Saxl.ferrers_rearrangement line 49

    Source comment

    A column-injective rearrangement of the canonical row word has precisely Ferrers support. This is the equality-of-margins argument, without using unproved Specht or Young-rule inputs.
    lemma ferrers_rearrangement {n : ℕ} {μ : YoungDiagram} (t : Tableau n μ)
        (g : Equiv.Perm (Fin n))
        (hinj : Function.Injective (fun i => ((t (g i)).val.1, (t i).val.2))) :
        ∀ i, ((t (g i)).val.1, (t i).val.2) ∈ μ := by
    …

    Mentions: OAI.Saxl.Tableau

  3. def OAI.Saxl.signC line 85

    Source comment

    The complex-valued sign character.
    def signC {n : ℕ} : Equiv.Perm (Fin n) →* ℂ :=
    …
  4. lemma OAI.Saxl.signC_def line 88
  5. lemma OAI.Saxl.signC_inv line 91
  6. lemma OAI.Saxl.signC_mul_self line 94
  7. lemma OAI.Saxl.wordRep_single line 98
  8. def OAI.Saxl.columnAlt line 117

    Source comment

    Actual column antisymmetrizer on the word-coordinate module.
    def columnAlt {n d : ℕ} {μ : YoungDiagram} (t : Tableau n μ) :
        Module.End ℂ (WordSpace n d) := by
    …

    Mentions: OAI.Saxl.Tableau, OAI.Saxl.WordSpace

  9. lemma OAI.Saxl.columnAlt_mul line 124
  10. lemma OAI.Saxl.columnAlt_row line 147
  11. lemma OAI.Saxl.column_rearrangement line 152

    Source comment

    Construction of the witnessing column rearrangement.
    lemma column_rearrangement {n : ℕ} {μ : YoungDiagram} (t : Tableau n μ)
        (g : Equiv.Perm (Fin n))
        (hinj : Function.Injective (fun i => ((t (g i)).val.1, (t i).val.2))) :
        ∃ h : columnGroup t, rowWord t ∘ g = rowWord t ∘ (h : Equiv.Perm (Fin n)) := by
    …

    Mentions: OAI.Saxl.Tableau, OAI.Saxl.columnGroup, OAI.Saxl.rowWord

  12. lemma OAI.Saxl.columnAlt_collision line 175
  13. lemma OAI.Saxl.columnAlt_column line 194
  14. lemma OAI.Saxl.columnAlt_single line 207