File size: 6,809 Bytes
a2ee19a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
import OAI.Probability.RadialTransition.MacroLower

namespace OAI

universe uX uY

noncomputable section


open Function MeasureTheory Set Filter

open scoped ContDiff BigOperators ENNReal NNReal

namespace RadialTransition

lemma measurable_countWeight {φ : Potential} (hφ : Continuous φ) (β : ℝ) (F : ℕ → ℝ) :
    Measurable (fun s : ParticleState Position => F (particleCount s)*Real.exp (-β*orderedEnergy φ s.2)) := by
  apply Continuous.measurable
  apply continuous_sigma
  intro n
  change Continuous (fun x : Fin n → Position => F n * Real.exp (-β*orderedEnergy φ x))
  exact continuous_const.mul (Real.continuous_exp.comp (continuous_const.mul (continuous_orderedEnergy hφ)))

lemma lintegral_countWeight {φ : Potential} (hφ : Continuous φ) (hb : IsBoundedPotential φ)
    (β z : ℝ) (F : ℕ → ℝ) (hF : ∀ n, 0 ≤ F n) {A : Set Position} (hAfin : volume A ≠ ⊤) :
    (∫⁻ s : ParticleState Position,
      ENNReal.ofReal (F (particleCount s)*Real.exp (-β*orderedEnergy φ s.2))
      ∂particleBase (volume.restrict A) z) =
    ∑' n : ℕ, ENNReal.ofReal (F n*Real.exp (z*n)*partitionOn φ A n β) := by
  let : IsFiniteMeasure (volume.restrict A) := isFiniteMeasure_restrict.mpr hAfin
  rw [lintegral_particleBase _ _ (measurable_countWeight hφ β F).ennreal_ofReal]
  apply tsum_congr
  intro n
  dsimp only [particleCount]
  have hi := (integrable_orderedBoltzmann (ι := Fin n) hφ hb β (Measure.pi (fun _ => volume.restrict A))).const_mul (F n)
  rw [← ofReal_integral_eq_lintegral_ofReal hi (Eventually.of_forall (fun x => mul_nonneg (hF n) (Real.exp_pos _).le)), integral_const_mul,
    ← ENNReal.ofReal_mul (by positivity)]
  congr 1
  simp only [partitionOn, rawPartition, div_eq_mul_inv]
  ring

lemma partitionOn_macroRegion (φ : Potential) {q : ℕ} (hq : 0 < q) (i : Cell) (n : ℕ) (β : ℝ) :
    partitionOn φ (macroRegion q i) n β = partition φ ((q:ℝ)/4) n β := by
  rw [macroRegion_translate hq, partitionOn_translate]
  have hh : partitionOn φ (halfCube ((q:ℝ)/4)) n β = partitionOn φ (cube ((q:ℝ)/4)) n β := by
    simp only [partitionOn, rawPartition, restrict_halfCube]
  rw [hh, partitionOn_cube]

section MapWeight
variable {X : Type uX} {Y : Type uY} [TopologicalSpace X] [MeasurableSpace X] [BorelSpace X]
    [TopologicalSpace Y] [MeasurableSpace Y] [BorelSpace Y]
    [SecondCountableTopology X] [SecondCountableTopology Y]

lemma lintegral_pairWeight_map (v : Y → Y → ℝ) (hv : Measurable (Function.uncurry v))
    (μ : Measure X) [IsFiniteMeasure μ] (f : X → Y) (hf : Measurable f) (β z : ℝ) (F : ℕ → ℝ) :
    (∫⁻ s : ParticleState X, ENNReal.ofReal (F (particleCount s)*Real.exp (-β*pairWithin (fun x y => v (f x) (f y)) s)) ∂particleBase μ z) =
    ∫⁻ s : ParticleState Y, ENNReal.ofReal (F (particleCount s)*Real.exp (-β*pairWithin v s)) ∂particleBase (Measure.map f μ) z := by
  have hfun : Measurable (fun s : ParticleState Y => ENNReal.ofReal (F (particleCount s)*Real.exp (-β*pairWithin v s))) := by
    apply Measurable.ennreal_ofReal
    exact (((continuous_of_discreteTopology : Continuous F).comp continuous_particleCount).measurable).mul
      (Real.measurable_exp.comp (measurable_const.mul (measurable_pairWithin v hv)))
  rw [← particleBase_map μ z hf, lintegral_map hfun (measurable_mapParticle hf)]
  rfl

end MapWeight

lemma lintegral_macroWeight {φ : Potential} (hφ : Continuous φ) (hb : IsBoundedPotential φ)
    {q : ℕ} (hq : 0 < q) (i : Cell) (β z : ℝ) (F : ℕ → ℝ) (hF : ∀ n, 0 ≤ F n) :
    (∫⁻ s : ParticleState (macroRegion q i), ENNReal.ofReal (F (particleCount s)*
      Real.exp (-β*pairWithin (fun (x y : macroRegion q i) => radialPair φ x y) s))
      ∂particleBase (regionMeasure (macroRegion q i)) z) =
    ∑' n : ℕ, ENNReal.ofReal (F n*Real.exp (z*n)*partition φ ((q:ℝ)/4) n β) := by
  have hfin : volume (macroRegion q i) ≠ ⊤ := by rw [volume_macroRegion hq]; finiteness
  let : IsFiniteMeasure (regionMeasure (macroRegion q i)) := regionMeasure_finite (measurableSet_macroRegion _ _) hfin
  rw [lintegral_pairWeight_map (radialPair φ) (continuous_radialPair hφ).measurable _ Subtype.val measurable_subtype_coe,
    regionMeasure_map (measurableSet_macroRegion _ _)]
  simp only [pairWithin_radial]
  rw [lintegral_countWeight hφ hb β z F hF hfin]
  simp only [partitionOn_macroRegion φ hq]

lemma integrable_macroWeight {φ : Potential} (hφ : Continuous φ) (hb : IsBoundedPotential φ)
    {q : ℕ} (hq : 0 < q) (i : Cell) (β z : ℝ) (F : ℕ → ℝ) (hF : ∀ n, 0 ≤ F n)
    (hs : Summable (fun n => F n*Real.exp (z*n)*partition φ ((q:ℝ)/4) n β)) :
    Integrable (fun s : ParticleState (macroRegion q i) => F (particleCount s)*
      Real.exp (-β*pairWithin (fun (x y : macroRegion q i) => radialPair φ x y) s))
      (particleBase (regionMeasure (macroRegion q i)) z) := by
  have hm : Measurable (fun s : ParticleState (macroRegion q i) => F (particleCount s)*
      Real.exp (-β*pairWithin (fun (x y : macroRegion q i) => radialPair φ x y) s)) := by
    exact ((continuous_of_discreteTopology.comp continuous_particleCount).measurable).mul
      (Real.measurable_exp.comp (measurable_const.mul (measurable_pairWithin _
        (continuous_radialPair_comp hφ continuous_subtype_val continuous_subtype_val).measurable)))
  apply (lintegral_ofReal_ne_top_iff_integrable hm.aestronglyMeasurable
    (Eventually.of_forall (fun s => mul_nonneg (hF _) (Real.exp_pos _).le))).mp
  rw [lintegral_macroWeight hφ hb hq i β z F hF,
    ← ENNReal.ofReal_tsum_of_nonneg (fun n => mul_nonneg (mul_nonneg (hF n) (Real.exp_pos _).le) (partition_nonneg _ _ _)) hs]
  exact ENNReal.ofReal_ne_top

lemma integral_macroWeight {φ : Potential} (hφ : Continuous φ) (hb : IsBoundedPotential φ)
    {q : ℕ} (hq : 0 < q) (i : Cell) (β z : ℝ) (F : ℕ → ℝ) (hF : ∀ n, 0 ≤ F n)
    (hs : Summable (fun n => F n*Real.exp (z*n)*partition φ ((q:ℝ)/4) n β)) :
    (∫ s : ParticleState (macroRegion q i), F (particleCount s)*
      Real.exp (-β*pairWithin (fun (x y : macroRegion q i) => radialPair φ x y) s)
      ∂particleBase (regionMeasure (macroRegion q i)) z) =
      ∑' n, F n*Real.exp (z*n)*partition φ ((q:ℝ)/4) n β := by
  rw [integral_eq_lintegral_of_nonneg_ae (Eventually.of_forall (fun s => mul_nonneg (hF _) (Real.exp_pos _).le))
    (integrable_macroWeight hφ hb hq i β z F hF hs).aestronglyMeasurable,
    lintegral_macroWeight hφ hb hq i β z F hF,
    ← ENNReal.ofReal_tsum_of_nonneg (fun n => mul_nonneg (mul_nonneg (hF n) (Real.exp_pos _).le) (partition_nonneg _ _ _)) hs,
    ENNReal.toReal_ofReal (tsum_nonneg (fun n => mul_nonneg (mul_nonneg (hF n) (Real.exp_pos _).le) (partition_nonneg _ _ _)))]

end RadialTransition

end

end OAI