OAI/GroupTheory/PolycyclicRecognition/Algebra/BoundedGeneratorSchemes.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

Quantitative bounds for a fixed generator scheme

The fixed conjugating words give a common amplitude bound; scaling a logarithm into the local product chart and repeating the resulting word covers any prescribed bounded logarithmic set.

  1. theorem OAI.PolycyclicRecognition.exists_fixed_word_amplitude_bound line 22

    Source documentation

    Amplitudes in every fixed conjugating word admit one finite bound.

    theorem exists_fixed_word_amplitude_bound {n : ℕ} (w : Fin n → List (I × ℝ)) :
        ∃ C : ℝ, 1 ≤ C ∧ ∀ k, ∀ p ∈ w k, |p.2| ≤ C := by
    …
  2. theorem OAI.PolycyclicRecognition.generatorSchemeWord_amplitude_bound line 39

    Source documentation

    Inserting unit-bounded parameters keeps every amplitude uniformly bounded.

    theorem generatorSchemeWord_amplitude_bound {n : ℕ} (w : Fin n → List (I × ℝ))
        (i : Fin n → I) {C : ℝ} (hC : 1 ≤ C)
        (hw : ∀ k, ∀ p ∈ w k, |p.2| ≤ C) (t : Fin n → ℝ) (ht : ‖t‖ ≤ 1) :
        ∀ p ∈ generatorSchemeWord w i t, |p.2| ≤ C := by
    …

    Mentions: OAI.PolycyclicRecognition.generatorSchemeWord

  3. theorem OAI.PolycyclicRecognition.exp_nat_smul line 68

    Source documentation

    The one-parameter identity identifies integer multiples with group powers.

    theorem exp_nat_smul (hzero : Exp 0 = 1)
        (hadd : ∀ v (s t : ℝ), Exp ((s + t) • v) = Exp (s • v) * Exp (t • v))
        (v : L) (k : ℕ) : Exp ((k : ℝ) • v) = (Exp v) ^ k := by
    …
  4. theorem OAI.PolycyclicRecognition.bounded_generation_of_local_scheme line 77

    Source documentation

    Any bounded logarithmic set is covered by words of uniformly bounded length and uniformly bounded generator amplitudes, for a fixed local scheme.

    theorem bounded_generation_of_local_scheme {n : ℕ}
        (w : Fin n → List (I × ℝ)) (i : Fin n → I)
        (hzero : Exp 0 = 1)
        (hadd : ∀ v (s t : ℝ), Exp ((s + t) • v) = Exp (s • v) * Exp (t • v))
        {ε : ℝ} (hε : 0 < ε)
        (hlocal : ∀ v : L, ‖v‖ < ε → ∃ t : Fin n → ℝ, ‖t‖ < 1 ∧
          generatorGroupWord X Exp (generatorSchemeWord w i t) = Exp v)
        (R : ℝ) :
        ∃ (N : ℕ) (C : ℝ), 1 ≤ C ∧ ∀ v : L, ‖v‖ ≤ R →
          ∃ u : List (I × ℝ), u.length ≤ N ∧ (∀ p ∈ u, |p.2| ≤ C) ∧
            generatorGroupWord X Exp u = Exp v := by
    …

    Mentions: OAI.PolycyclicRecognition.generatorGroupWord, OAI.PolycyclicRecognition.generatorSchemeWord