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Add lean source and binary files (part 83)
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import Mathlib
import OAI.GroupTheory.SimpleAmenable.RandomFields.ThresholdField
namespace OAI
section
section
open scoped symmDiff
namespace SimpleAmenable
open scoped commutatorElement
open scoped commutatorElement
section BitReindex
open Classical MeasureTheory
noncomputable def bitReindex {ι : Type*} (e : ι ≃ ι) (b : ι → Bool) : ι → Bool :=
fun z => b (e.symm z)
theorem bitReindex_measurable {ι : Type*} (e : ι ≃ ι) : Measurable (bitReindex e) :=
Measurable.of_eval (fun z => measurable_pi_apply (e.symm z))
theorem thresholdField_transport {ι : Type*} (μ : Measure (ι → ℝ)) (e : ι ≃ ι) :
(μ.map (fieldReindex e)).map thresholdField=
(μ.map thresholdField).map (bitReindex e) := by
rw [Measure.map_map thresholdField_measurable (fieldReindex_measurable e),
Measure.map_map (bitReindex_measurable e) thresholdField_measurable]
rfl
theorem ObservableClose.threshold_transport {ι : Type*} (μ : Measure (ι → ℝ))
(e : ι ≃ ι) {ε : ℝ} (h : ObservableClose μ (μ.map (fieldReindex e)) ε) :
ObservableClose (μ.map thresholdField) ((μ.map thresholdField).map (bitReindex e)) ε := by
have hh := h.map thresholdField_measurable
rw [thresholdField_transport] at hh
exact hh
end BitReindex
end SimpleAmenable
end
end
end OAI