File size: 2,804 Bytes
92416a2
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
import Mathlib
import OAI.Computability.VertexCover.Analysis.PoincareOne

namespace OAI

section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
section
namespace VertexCover.Cube
open MeasureTheory ProbabilityTheory
open scoped ENNReal

theorem law_eq_restrict_volume (ι : Type*) [Fintype ι] :
    law ι = (1/2 : ℝ≥0∞) ^ Fintype.card ι •
    volume.restrict (Set.univ.pi (fun _ : ι => Set.Icc (-1 : ℝ) 1)) := by
  apply Measure.pi_eq
  intro s hs
  rw [Measure.smul_apply, Measure.restrict_apply (MeasurableSet.univ_pi hs),
    ← Set.pi_inter_distrib, volume_pi_pi]
  simp only [intervalLaw, Measure.smul_apply, Measure.restrict_apply (hs _),
    smul_eq_mul, Finset.prod_mul_distrib, Finset.prod_const, Finset.card_univ]

theorem law_ac (ι : Type*) [Fintype ι] : law ι ≪ volume := by
  rw [law_eq_restrict_volume]
  intro s hs
  have hz : volume.restrict (Set.univ.pi (fun _ : ι => Set.Icc (-1 : ℝ) 1)) s = 0 :=
    le_antisymm ((Measure.restrict_le_self s).trans_eq hs) zero_le
  simp only [Measure.smul_apply, hz, smul_zero]

end VertexCover.Cube

namespace VertexCover.Cube
open MeasureTheory ProbabilityTheory
open scoped ENNReal

noncomputable def blockLaw (ι κ : Type*) [Fintype ι] [Fintype κ] :
    Measure (ι → κ → ℝ) := Measure.pi (fun _ : ι => law κ)

instance blockLaw_probability (ι κ : Type*) [Fintype ι] [Fintype κ] :
    IsProbabilityMeasure (blockLaw ι κ) := by
  unfold blockLaw
  infer_instance

theorem blockLaw_eq_restrict_volume (ι κ : Type*) [Fintype ι] [Fintype κ] :
    blockLaw ι κ = ((1/2 : ℝ≥0∞) ^ Fintype.card κ) ^ Fintype.card ι •
      volume.restrict (Set.univ.pi (fun _ : ι =>
        Set.univ.pi (fun _ : κ => Set.Icc (-1 : ℝ) 1))) := by
  apply Measure.pi_eq
  intro s hs
  rw [Measure.smul_apply, Measure.restrict_apply (MeasurableSet.univ_pi hs),
    ← Set.pi_inter_distrib, volume_pi_pi]
  simp only [law_eq_restrict_volume, Measure.smul_apply,
    Measure.restrict_apply (hs _), smul_eq_mul, Finset.prod_mul_distrib,
    Finset.prod_const, Finset.card_univ]

theorem blockLaw_ac (ι κ : Type*) [Fintype ι] [Fintype κ] :
    blockLaw ι κ ≪ volume := by
  rw [blockLaw_eq_restrict_volume]
  intro s hs
  have hz : volume.restrict (Set.univ.pi (fun _ : ι =>
      Set.univ.pi (fun _ : κ => Set.Icc (-1 : ℝ) 1))) s = 0 :=
    le_antisymm ((Measure.restrict_le_self s).trans_eq hs) zero_le
  simp only [Measure.smul_apply, hz, smul_zero]

end VertexCover.Cube


end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end

end OAI