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Add lean source and binary files (part 18)
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import Mathlib
import OAI.Analysis.HardSphere.Geometry.AuxiliaryChecks
namespace OAI
section
section
noncomputable section
open MeasureTheory ProbabilityTheory Set
open scoped ENNReal
namespace HardSphere.Comparison
variable {I C : Type*} [Fintype I] [DecidableEq I] [Fintype C]
{X : I → Type*} [∀i,MeasurableSpace (X i)]
def freezeOutside (U : Finset I) (x y : ∀i,X i) : ∀i,X i :=
fun i ↦ if i∈U then y i else x i
omit [Fintype I] in
lemma freezeOutside_measurable (U : Finset I) (x : ∀i,X i) : Measurable (freezeOutside U x) := by
apply Measurable.of_eval
intro i
by_cases hi : i∈U
· simpa only [freezeOutside,ite_eq_left hi] using (measurable_pi_apply i)
· simp only [freezeOutside,ite_eq_right hi]
exact measurable_const
omit [Fintype I] [∀i,MeasurableSpace (X i)] in
lemma freezeOutside_update (U : Finset I) (x y : ∀i,X i) {i : I} (hi : i∈U) (v : X i) :
freezeOutside U x (Function.update y i v)=Function.update (freezeOutside U x y) i v := by
funext j
by_cases hj : j=i
· subst j;simp [freezeOutside,hi]
· simp [freezeOutside,Function.update_of_ne hj]
def FrozenCheckIndex (checks : C → LocalCheck X) (U : Finset I) :=
{c : C // ((checks c).support∩U).Nonempty}
instance (checks : C → LocalCheck X) (U : Finset I) : Fintype (FrozenCheckIndex checks U) :=
by
classical
unfold FrozenCheckIndex
infer_instance
def frozenChecks (checks : C → LocalCheck X) (U : Finset I) (x : ∀i,X i) :
FrozenCheckIndex checks U → LocalCheck X := fun c ↦ {
support := (checks c.val).support∩U
nonempty := c.property
arity := (Finset.card_le_card Finset.inter_subset_left).trans (checks c.val).arity
pass := fun y ↦ (checks c.val).pass (freezeOutside U x y)
measurable_pass := (checks c.val).measurable_pass.preimage (freezeOutside_measurable U x)
depends := by
intro y z hyz
apply (checks c.val).depends
intro i hi
by_cases hu : i∈U
· simp only [freezeOutside,ite_eq_left hu]
exact hyz i (Finset.mem_inter.mpr ⟨hi,hu⟩)
· simp only [freezeOutside,ite_eq_right hu]
}
omit [Fintype C]
lemma frozen_support_subset (checks : C → LocalCheck X) (U t : Finset I) (c : C) :
(checks c).support ⊆ t∪(Finset.univ \ U) ↔ (checks c).support∩U ⊆t := by
constructor
· intro h i hi
rcases Finset.mem_union.mp (h (Finset.mem_inter.mp hi).1) with ht|ho
· exact ht
· exact False.elim ((Finset.mem_sdiff.mp ho).2 (Finset.mem_inter.mp hi).2)
· intro h i hi
by_cases hu : i∈U
· exact Finset.mem_union_left _ (h (Finset.mem_inter.mpr ⟨hi,hu⟩))
· exact Finset.mem_union_right _ (Finset.mem_sdiff.mpr ⟨Finset.mem_univ _,hu⟩)
lemma frozen_retained (checks : C → LocalCheck X) (U t : Finset I) (x y : ∀i,X i)
(hx : x∈retainedEvent checks (Finset.univ \ U)) :
y∈retainedEvent (frozenChecks checks U x) t ↔
freezeOutside U x y∈retainedEvent checks (t∪(Finset.univ \ U)) := by
constructor
· intro hy c hc
by_cases he : ((checks c).support∩U).Nonempty
· exact hy ⟨c,he⟩ ((frozen_support_subset checks U t c).mp hc)
· have hout : (checks c).support⊆Finset.univ \ U := by
intro i hi
refine Finset.mem_sdiff.mpr ⟨Finset.mem_univ _,?_⟩
intro hu
exact he ⟨i,Finset.mem_inter.mpr ⟨hi,hu⟩⟩
apply ((checks c).depends x (freezeOutside U x y) ?_).mp (hx c hout)
intro i hi
simp only [freezeOutside,ite_eq_right (Finset.mem_sdiff.mp (hout hi)).2]
· intro hy c hc
exact hy c.val ((frozen_support_subset checks U t c.val).mpr hc)
lemma frozen_checkWeight (checks : C → LocalCheck X) (U t : Finset I) (x y : ∀i,X i)
(hx : x∈retainedEvent checks (Finset.univ \ U)) :
checkWeight (frozenChecks checks U x) t y=
checkWeight checks (t∪(Finset.univ \ U)) (freezeOutside U x y) := by
classical
simp only [checkWeight,Set.indicator_apply,frozen_retained checks U t x y hx]
lemma frozen_insertion (checks : C → LocalCheck X) (U s : Finset I) (x y : ∀i,X i) (i : I) :
freezeOutside U x y∈insertionEvent checks (s∪(Finset.univ \ U)) i →
y∈insertionEvent (frozenChecks checks U x) s i := by
intro hy c hc hcs
apply hy c.val
· rw [←Finset.insert_union]
exact (frozen_support_subset checks U (insert i s) c.val).mpr hc
· intro hs
exact hcs ((frozen_support_subset checks U s c.val).mp hs)
lemma frozen_uniformInsertion (checks : C → LocalCheck X) (U : Finset I) (x : ∀i,X i)
(μ : ∀i,Measure (X i)) {a : ℝ≥0∞}
(h : UniformInsertionOn checks μ a U) :
UniformInsertionOn (frozenChecks checks U x) μ a U := by
intro i hi s his y
have hin : i∉s∪(Finset.univ \ U) := by simp [Finset.mem_union,his,hi]
apply (h i hi (s∪(Finset.univ \ U)) hin (freezeOutside U x y)).trans
apply lintegral_mono
intro v
dsimp only
rw [←freezeOutside_update U x y hi v]
by_cases hp : freezeOutside U x (Function.update y i v)∈insertionEvent checks (s∪(Finset.univ \ U)) i
· rw [Set.indicator_of_mem hp,Set.indicator_of_mem (frozen_insertion checks U s x (Function.update y i v) i hp)]
· rw [Set.indicator_of_notMem hp]
exact bot_le
end HardSphere.Comparison
end
end
end
end OAI