OAI/GroupTheory/PolycyclicRecognition/Geometry/CartanBoxDilation.lean

GitHub source file

7 declarations, 0 contain sorry, 0 declared as axioms

Exact template shifts for actual Cartan boxes

The scalar action on generalized weight spaces is a genuine Lie automorphism. It takes each scaled word basis to the basis for the translated template. The finite Dynkin identity then integrates it to the needed group automorphism.

  1. theorem OAI.PolycyclicRecognition.CartanWordModel.idealWeightDilation_word line 31

    Source documentation

    Every actual bracket word is scaled by the exponential of its total weight, even when its total weight is zero.

    theorem idealWeightDilation_word (h : H) (w : FreeMagma (Fin M.letterCount)) :
        cartanIdealWeightDilation T H h (evalBracketWord M.letter w) =
          Real.exp (bracketWordExponent (fun i => M.weight i h) w) • evalBracketWord M.letter w := by
    …

    Mentions: OAI.PolycyclicRecognition.cartanIdealWeightDilation, OAI.PolycyclicRecognition.evalBracketWord, OAI.PolycyclicRecognition.bracketWordExponent

  2. theorem OAI.PolycyclicRecognition.CartanWordModel.boxCost_translate line 47

    Source documentation

    Translation adds the total word weight to its box exponent.

    theorem boxCost_translate {E : Set W} (hE : IsCompact E) (hne : E.Nonempty)
        (w : W) (z : M.wordList) :
        M.boxCost T hunimod eW ((fun x => x + w) '' E) z =
          M.boxCost T hunimod eW E z +
            bracketWordExponent (fun i => M.weight i (cartanHeightSection T H (eW.symm w))) z := by
    …

    Mentions: OAI.PolycyclicRecognition.bracketWordExponent, OAI.PolycyclicRecognition.cartanHeightSection

  3. theorem OAI.PolycyclicRecognition.CartanWordModel.columnBasisWeight_boxCost_translate line 61

    Source documentation

    All word bases keep their determinant exponent under template translation.

    theorem columnBasisWeight_boxCost_translate {E : Set W}
        (hE : IsCompact E) (hne : E.Nonempty) (w : W) (β : M.Bases) :
        columnBasisWeight (M.boxCost T hunimod eW ((fun x => x + w) '' E)) β.val =
          columnBasisWeight (M.boxCost T hunimod eW E) β.val := by
    …

    Mentions: OAI.PolycyclicRecognition.columnBasisWeight

  4. theorem OAI.PolycyclicRecognition.CartanWordModel.maximizing_box_basis_translate line 69

    Source documentation

    Thus a maximizing basis remains maximizing after translation.

    theorem maximizing_box_basis_translate
        (b₀ : Basis (Fin (finrank ℝ (cartanRootIdeal H))) ℝ (cartanRootIdeal H))
        {E : Set W} (hE : IsCompact E) (hne : E.Nonempty) (w : W) (β : M.Bases)
        (hβ : IsMaximizingColumnBasis (wordListCoordinates M.letter M.wordList b₀)
          (M.boxCost T hunimod eW E) β.val) :
        IsMaximizingColumnBasis (wordListCoordinates M.letter M.wordList b₀)
          (M.boxCost T hunimod eW ((fun x => x + w) '' E)) β.val := by
    …

    Mentions: OAI.PolycyclicRecognition.cartanRootIdeal, OAI.PolycyclicRecognition.IsMaximizingColumnBasis, OAI.PolycyclicRecognition.wordListCoordinates

  5. theorem OAI.PolycyclicRecognition.CartanWordModel.idealWeightDilation_boxBasis line 85

    Source documentation

    The scaled basis itself shifts exactly, with no loss in its radius.

    theorem idealWeightDilation_boxBasis {E : Set W} (hE : IsCompact E) (hne : E.Nonempty)
        (w : W) (β : M.Bases) (r : ℝ) :
        (M.boxBasis T hunimod eW E β r).map
          (cartanIdealWeightDilation T H (r • cartanHeightSection T H (eW.symm w))).toLinearEquiv =
            M.boxBasis T hunimod eW ((fun x => x + w) '' E) β r := by
    …

    Mentions: OAI.PolycyclicRecognition.cartanIdealWeightDilation, OAI.PolycyclicRecognition.cartanHeightSection

  6. def OAI.PolycyclicRecognition.CartanWordModel.groupWeightDilation line 124

    Source documentation

    Exact weight dilation in the actual nilpotent group.

    def groupWeightDilation (w : W) (r : ℝ) : N ≃* N :=
    …
  7. theorem OAI.PolycyclicRecognition.CartanWordModel.groupWeightDilation_box line 129

    Source documentation

    The exponential image of a coordinate cube shifts with its basis.

    theorem groupWeightDilation_box {E : Set W} (hE : IsCompact E) (hne : E.Nonempty)
        (w : W) (β : M.Bases) (r R : ℝ) :
        M.groupWeightDilation T eW eN Exp hExp hbij dynkin w r ''
          M.groupBox T hunimod eW (Exp ∘ eN) E β r R =
            M.groupBox T hunimod eW (Exp ∘ eN) ((fun x => x + w) '' E) β r R := by
    …