OAI/GroupTheory/PolycyclicRecognition/Geometry/ParametricLieWords.lean

GitHub source file

7 declarations, 0 contain sorry, 0 declared as axioms

Lie words as functions of their structure constants

The bilinear bracket itself varies in a finite-dimensional vector space. Word evaluation is smooth jointly in that bracket and the input vectors, so word identities and normalization equations persist under limits.

  1. theorem OAI.PolycyclicRecognition.norm_bilinear_le_of_bound line 24

    Source documentation

    A bound on bilinear evaluations bounds the iterated operator norm.

    theorem norm_bilinear_le_of_bound (B : V →L[ℝ] V →L[ℝ] V) {C : ℝ}
        (hC : 0 ≤ C) (h : ∀ x y, ‖B x y‖ ≤ C * ‖x‖ * ‖y‖) : ‖B‖ ≤ C := by
    …
  2. def OAI.PolycyclicRecognition.evalBilinearWord line 32

    Source documentation

    Evaluate a bracket word with a specified continuous bilinear bracket.

    def evalBilinearWord (B : V →L[ℝ] V →L[ℝ] V) (X : I → V) : FreeMagma I → V
      | .of i => X i
      | .mul a b => B (evalBilinearWord B X a) (evalBilinearWord B X b)
    
    variable {P : Type*} [NormedAddCommGroup P] [NormedSpace ℝ P]
      {n : ℕ∞}
    
    /-- Smooth dependence of a finite word on both bracket and generator data. -/
  3. theorem OAI.PolycyclicRecognition.contDiff_evalBilinearWord line 40

    Source documentation

    Smooth dependence of a finite word on both bracket and generator data.

    theorem contDiff_evalBilinearWord (B : P → V →L[ℝ] V →L[ℝ] V)
        (X : P → I → V) (hB : ContDiff ℝ n B)
        (hX : ∀ i, ContDiff ℝ n (fun p => X p i)) (w : FreeMagma I) :
        ContDiff ℝ n (fun p => evalBilinearWord (B p) (X p) w) := by
    …

    Mentions: OAI.PolycyclicRecognition.evalBilinearWord

  4. def OAI.PolycyclicRecognition.IsLieBracket line 50

    Source documentation

    The defining identities of a real Lie bracket, with bilinearity supplied by its continuous-linear-map type.

    def IsLieBracket (B : V →L[ℝ] V →L[ℝ] V) : Prop :=
    …
  5. theorem OAI.PolycyclicRecognition.isClosed_setOf_isLieBracket line 54

    Source documentation

    Alternation and Jacobi are closed conditions on the bracket.

    theorem isClosed_setOf_isLieBracket :
        IsClosed {B : V →L[ℝ] V →L[ℝ] V | IsLieBracket B} := by
    …

    Mentions: OAI.PolycyclicRecognition.IsLieBracket

  6. theorem OAI.PolycyclicRecognition.isClosed_bilinearWord_eq line 71

    Source documentation

    A fixed word equation is closed even while both bracket and generators vary. This is the normalization condition used by rescaled word bases.

    theorem isClosed_bilinearWord_eq [Fintype I] (w : FreeMagma I) (v : V) :
        IsClosed {p : (V →L[ℝ] V →L[ℝ] V) × (I → V) |
          evalBilinearWord p.1 p.2 w = v} := by
    …

    Mentions: OAI.PolycyclicRecognition.evalBilinearWord

  7. theorem OAI.PolycyclicRecognition.isClosed_wordNormalizations line 81

    Source documentation

    All finite word-normalization equations hold on a closed parameter set.

    theorem isClosed_wordNormalizations [Fintype I] {J : Type*}
        (w : J → FreeMagma I) (v : J → V) :
        IsClosed {p : (V →L[ℝ] V →L[ℝ] V) × (I → V) |
          ∀ j, evalBilinearWord p.1 p.2 (w j) = v j} := by
    …

    Mentions: OAI.PolycyclicRecognition.evalBilinearWord