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Add lean source and binary files (part 83)
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import Mathlib
import OAI.GroupTheory.SimpleAmenable.PolygonGeometry.FlagSites
import OAI.GroupTheory.SimpleAmenable.RandomFields.UniformThresholdCDF
namespace OAI
section
section
open scoped symmDiff
namespace SimpleAmenable
open scoped commutatorElement
open scoped commutatorElement
section FlagArrangementControl
open Classical MeasureTheory
theorem flagValue_arrangement {a : ℕ} {v : ℝ×ℝ} {K : Type*}
(f : GenericSquare a → K) (S : Finset PlaneCut)
(hS : ∀p q,(∀l∈S,squareSign l p=squareSign l q) → f p=f q)
(z w : SquareFlag a v)
(hs : ∀l∈S,¬ FlagSeparates l.1 l.2 z w) :
flagValue f ⟨S,hS⟩ z=flagValue f ⟨S,hS⟩ w := by
obtain ⟨N,hN,hz,hf⟩ := flagValue_spec f ⟨S,hS⟩ z
obtain ⟨M,hM,hw,hg⟩ := flagValue_spec f ⟨S,hS⟩ w
obtain ⟨p,hp,hpv⟩ := squareSector_generic z (hN.inter (arrangementNeighborhood_open a S z.val))
⟨hz,self_mem_arrangementNeighborhood a S z.val⟩
obtain ⟨q,hq,hqv⟩ := squareSector_generic w (hM.inter (arrangementNeighborhood_open a S w.val))
⟨hw,self_mem_arrangementNeighborhood a S w.val⟩
rw [← hf p hp.1 hpv,← hg q hq.1 hqv]
apply hS p q
intro l hl
have h₁ := planeSign_neighborhood (p:=⟨p.val,p.property.2.2⟩) hp.2 hpv hl
have h₂ := planeSign_neighborhood (p:=⟨q.val,q.property.2.2⟩) hq.2 hqv hl
change squareSign l p=_ at h₁
change squareSign l q=_ at h₂
rw [h₁,h₂]
apply decide_eq_decide.mpr
have h := not_not.mp (hs l hl)
simpa only [flagMem_halfPlane] using h
theorem flagMem_arrangement {a : ℕ} {v : ℝ×ℝ} (U : polygonAlgebra a) :
∃S : Finset PlaneCut,∀z w : SquareFlag a v,
(∀l∈S,¬ FlagSeparates l.1 l.2 z w) → (flagMem U z ↔ flagMem U w) := by
obtain ⟨S,hS⟩ := polygon_hasSquareArrangement U.property
refine ⟨S,fun z w h => ?_⟩
unfold flagMem
rw [flagValue_arrangement (fun p => decide (p∈U.val)) S hS z w h]
theorem separatorMatrix_zero_of_cut {a : ℕ} {v : ℝ×ℝ}
{s κ : ℝ} (hs : 0 < s) (hκ : 0 < κ) (z w : SquareFlag a v)
(j : Fin 4) (c : CutRing) (hc : FlagSeparates j c z w)
(hcut : |conjugate c| ≤ κ/s) :
separatorMatrix (thresholdLaw s κ) z w=0 := by
obtain ⟨d,hd,hdmin⟩ := flagSeparates_exists_min j z w ⟨c,hc⟩
have h : κ/s < 2*κ/s := (div_lt_div_iff_of_pos_right hs).mpr (by linarith)
have hd' : |conjugate d| ≤ κ/s := (hdmin c hc).trans hcut
have hp : directionNoCutProbability s κ j z w=0 := by
rw [directionNoCutProbability,directionNoCut_of_min j z w d hd hdmin,
uniformInterval_Iio h,intervalCDF]
rw [max_eq_right (by linarith [min_le_right (2*κ/s) |conjugate d|]),zero_div]
rw [separatorMatrix_product hs hκ]
exact Finset.prod_eq_zero (Finset.mem_univ j) hp
theorem separatorMatrix_ne_zero_signs {a : ℕ} {v : ℝ×ℝ}
{s κ : ℝ} (hs : 0 < s) (hκ : 0 < κ) (S : Finset PlaneCut)
(hS : ∀l∈S,|conjugate l.2| ≤ κ/s) (z w : SquareFlag a v)
(hp : separatorMatrix (thresholdLaw s κ) z w ≠ 0) :
∀l∈S,¬ FlagSeparates l.1 l.2 z w := by
intro l hl hsep
exact hp (separatorMatrix_zero_of_cut hs hκ z w l.1 l.2 hsep (hS l hl))
theorem separatorMatrix_controls_step {a : ℕ} {v : ℝ×ℝ} {K : Type*}
(f : GenericSquare a → K) (hf : HasSquareArrangement f) :
∃R : ℝ, 0 ≤ R ∧ ∀(s κ : ℝ),0 < s → 0 < κ → R ≤ κ/s →
∀z w : SquareFlag a v,separatorMatrix (thresholdLaw s κ) z w ≠ 0 →
flagValue f hf z=flagValue f hf w := by
obtain ⟨S,hS⟩ := hf
let R := ∑l∈S,|conjugate l.2|
have hR : 0 ≤ R := Finset.sum_nonneg (fun _ _ => abs_nonneg _)
refine ⟨R,hR,fun s κ hs hκ hRs z w hp => ?_⟩
apply flagValue_arrangement f S hS z w
apply separatorMatrix_ne_zero_signs hs hκ S _ z w hp
intro l hl
exact (Finset.single_le_sum (fun _ _ => abs_nonneg _) hl).trans hRs
end FlagArrangementControl
section SquareAffineCharts
open Classical
theorem floor_add_unit {x : ℝ} (hx₀ : 0 ≤ x) (hx₁ : x < 1) (y : ℝ) :
⌊x+y⌋ = ⌊y⌋ + if x < 1-Int.fract y then 0 else 1 := by
have hy₀ := Int.floor_le y
have hy₁ := Int.lt_floor_add_one y
by_cases h : x < 1-Int.fract y
· rw [ite_eq_left h,add_zero]
simp only [Int.fract] at h
apply Int.floor_eq_iff.mpr
constructor <;> linarith
· rw [ite_eq_right h]
simp only [Int.fract] at h
apply Int.floor_eq_iff.mpr
push_cast
constructor <;> linarith
noncomputable def squareTranslationPeriod {a : ℕ} (u : CutRing×CutRing)
(p : GenericSquare a) : ℤ×ℤ :=
(⌊p.val.1+ordinary u.1⌋,⌊p.val.2+ordinary u.2⌋)
theorem squareTranslationPeriod_arrangement {a : ℕ} (u : CutRing×CutRing) :
HasSquareArrangement (squareTranslationPeriod (a:=a) u) := by
let c₁ : CutRing := (⌊ordinary u.1⌋:CutRing)+1-u.1
let c₂ : CutRing := (⌊ordinary u.2⌋:CutRing)+1-u.2
have hc₁ : ordinary c₁=1-Int.fract (ordinary u.1) := by simp only [c₁,map_sub,map_add,map_intCast,map_one,Int.fract]; ring
have hc₂ : ordinary c₂=1-Int.fract (ordinary u.2) := by simp only [c₂,map_sub,map_add,map_intCast,map_one,Int.fract]; ring
refine ⟨{(0,c₁),(1,c₂)},fun p q h => ?_⟩
have h₁ := decide_eq_decide.mp (h (0,c₁) (by simp))
have h₂ := decide_eq_decide.mp (h (1,c₂) (by simp))
change (p.val.1<ordinary c₁ ↔ q.val.1<ordinary c₁) at h₁
change (p.val.2<ordinary c₂ ↔ q.val.2<ordinary c₂) at h₂
rw [hc₁] at h₁
rw [hc₂] at h₂
apply Prod.ext
· change ⌊p.val.1+ordinary u.1⌋=⌊q.val.1+ordinary u.1⌋
rw [floor_add_unit p.property.1.1 p.property.1.2,floor_add_unit q.property.1.1 q.property.1.2]
simp only [h₁]
· change ⌊p.val.2+ordinary u.2⌋=⌊q.val.2+ordinary u.2⌋
rw [floor_add_unit p.property.2.1.1 p.property.2.1.2,floor_add_unit q.property.2.1.1 q.property.2.1.2]
simp only [h₂]
theorem squareTranslationPeriod_germ {a : ℕ} {v : ℝ×ℝ}
(u : CutRing×CutRing) (z : SquareFlag a v) :
IsSquareGerm (squareTranslationPeriod u) z (flagShiftPeriod u z) := by
let k := flagShiftPeriod u z
let t := u-SquareStep.intPair k
let b : ℝ×ℝ := (ordinary t.1,ordinary t.2)
have hbase : (flagTranslate u z).val=z.val+b := by
apply Prod.ext <;> simp only [flagTranslate_val,flagFract_eq,b,t,k,flagShiftPeriod,SquareStep.intPair,
Prod.fst_sub,Prod.snd_sub,Prod.fst_add,Prod.snd_add,map_sub,map_intCast] <;> ring
let M : Set (ℝ×ℝ) := (fun p => p+b) ⁻¹' arrangementNeighborhood a SquareStep.squareEdgeCuts (flagTranslate u z).val
refine ⟨M,(arrangementNeighborhood_open _ _ _).preimage (continuous_id.add continuous_const),?_,fun p hp hpv => ?_⟩
· change z.val+b ∈ arrangementNeighborhood a SquareStep.squareEdgeCuts (flagTranslate u z).val
rw [← hbase]
exact self_mem_arrangementNeighborhood _ _ _
· let q : GenericPlane a := GenericPlane.shift t ⟨p.val,p.property.2.2⟩
have hqv : q.val ∈ planeSector a (flagTranslate u z).val v := by
rw [hbase]
exact (planeSector_add_iff z.val v b p.val).mpr hpv
have hpq : q.val ∈ arrangementNeighborhood a SquareStep.squareEdgeCuts (flagTranslate u z).val := hp
have hqs := sector_enters_square (flagTranslate u z).property.2 hpq hqv
have hx : 0 ≤ p.val.1+ordinary u.1-(k.1:ℝ) ∧ p.val.1+ordinary u.1-(k.1:ℝ) < 1 := by
simpa only [q,GenericPlane.shift,t,SquareStep.intPair,Prod.fst_add,Prod.fst_sub,map_sub,map_intCast,← add_sub_assoc,Set.mem_Ico] using hqs.1
have hy : 0 ≤ p.val.2+ordinary u.2-(k.2:ℝ) ∧ p.val.2+ordinary u.2-(k.2:ℝ) < 1 := by
simpa only [q,GenericPlane.shift,t,SquareStep.intPair,Prod.snd_add,Prod.snd_sub,map_sub,map_intCast,← add_sub_assoc,Set.mem_Ico] using hqs.2
apply Prod.ext
· exact Int.floor_eq_iff.mpr ⟨by linarith [hx.1],by linarith [hx.2]⟩
· exact Int.floor_eq_iff.mpr ⟨by linarith [hy.1],by linarith [hy.2]⟩
theorem squareTranslationPeriod_flagValue {a : ℕ} {v : ℝ×ℝ}
(u : CutRing×CutRing) (z : SquareFlag a v) :
flagValue (squareTranslationPeriod u) (squareTranslationPeriod_arrangement u) z=flagShiftPeriod u z :=
flagValue_eq _ _ _ (squareTranslationPeriod_germ u z)
theorem squareArrangement_pair {a : ℕ} {K J : Type*} {f : GenericSquare a → K} {g : GenericSquare a → J}
(hf : HasSquareArrangement f) (hg : HasSquareArrangement g) :
HasSquareArrangement (fun p => (f p,g p)) := by
obtain ⟨S,hS⟩ := hf
obtain ⟨T,hT⟩ := hg
refine ⟨S∪T,fun p q h => Prod.ext (hS p q (fun l hl => h l (Finset.mem_union_left _ hl)))
(hT p q (fun l hl => h l (Finset.mem_union_right _ hl)))⟩
theorem squareArrangement_finite_family {a : ℕ} {ι K : Type*} [Finite ι]
(f : ι → GenericSquare a → K) (hf : ∀i,HasSquareArrangement (f i)) :
HasSquareArrangement (fun p i => f i p) := by
let := Fintype.ofFinite ι
choose S hS using hf
refine ⟨Finset.univ.biUnion S,fun p q h => funext (fun i => hS i p q (fun l hl => ?_))⟩
exact h l (Finset.mem_biUnion.mpr ⟨i,Finset.mem_univ _,hl⟩)
end SquareAffineCharts
end SimpleAmenable
end
end
end OAI