OAI/GroupTheory/PolycyclicRecognition/Geometry/CartanResidualAction.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

Polynomial bounds for the residual Cartan action

On an actual generalized root space, subtracting its scalar character leaves an operator nilpotent in a uniform dimension bound. Its exponential therefore has polynomial growth in the Cartan parameter. This supplies the residual operator estimate used in box conjugation.

  1. theorem OAI.PolycyclicRecognition.exp_eq_scalar_smul_residual line 21

    Source documentation

    Split an arbitrary scalar character from an operator exponential.

    theorem exp_eq_scalar_smul_residual
        {A : Type*} [NormedRing A] [NormedAlgebra ℝ A] [CompleteSpace A]
        (a : ℝ) (X : A) :
        NormedSpace.exp X = Real.exp a • NormedSpace.exp (X - a • 1) := by
    …
  2. theorem OAI.PolycyclicRecognition.rootAction_residual_pow_eq_zero line 47

    Source documentation

    The nilpotence exponent is uniformly bounded by the root-space dimension.

    theorem rootAction_residual_pow_eq_zero (h : H) :
        (rootAction H χ h - χ h • 1) ^ finrank ℝ (rootSpace H χ) = 0 := by
    …

    Mentions: OAI.PolycyclicRecognition.rootAction

  3. def OAI.PolycyclicRecognition.rootResidualLinear line 58

    Source documentation

    Dependence of the residual operator on the Cartan parameter is linear.

    def rootResidualLinear : H →ₗ[ℝ] ((rootSpace H χ) →L[ℝ] (rootSpace H χ)) where
    …
  4. theorem OAI.PolycyclicRecognition.exists_rootResidual_exp_bound line 72

    Source documentation

    One polynomial controls the residual operator for every Cartan parameter.

    theorem exists_rootResidual_exp_bound :
        ∃ C : ℝ, 0 < C ∧ ∀ h : H,
          ‖NormedSpace.exp (rootAction H χ h - χ h • 1)‖ ≤
            C * (1 + ‖(Module.finBasis ℝ H).equivFun h‖) ^ finrank ℝ (rootSpace H χ) := by
    …

    Mentions: OAI.PolycyclicRecognition.rootAction

  5. theorem OAI.PolycyclicRecognition.exists_rootAction_exp_bound line 101

    Source documentation

    Restoring the scalar character gives the full root action estimate.

    theorem exists_rootAction_exp_bound :
        ∃ C : ℝ, 0 < C ∧ ∀ (h : H) (v : rootSpace H χ),
          ‖(NormedSpace.exp (rootAction H χ h)) v‖ ≤
            C * (1 + ‖(Module.finBasis ℝ H).equivFun h‖) ^ finrank ℝ (rootSpace H χ) * Real.exp (χ h) * ‖v‖ := by
    …

    Mentions: OAI.PolycyclicRecognition.rootAction