File size: 8,269 Bytes
8e4d533
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
import OAI.Geometry.BundleTests.Smooth
import OAI.Geometry.ComplexBundle.CoordinatesMetric

namespace OAI

noncomputable section

/-! Fresh bundle maps and assembly of the test-bundle step. -/

section
open Bundle Topology Module
open scoped Manifold ContDiff
namespace Kaplansky
open ComplexGrassmann

theorem testBundleSlot_card {m R j : ℕ} (hj : j≤R) :
    Fintype.card (TestBundleSlot m R j) = testRank m R j := by
  simpa [TestBundleSlot] using (sum_testMultiplicity (m := m) hj)

abbrev TestSourceCoordinates (m R j : ℕ) (hj : j<R) :=
  FiniteCoordinateBundle (stageProjectiveDimensions m R (j+1) hj)
    (fun s : TestBundleSlot m R j => testSummandLineIndex (Nat.le_succ j) s.1)
    (testRank m R j) (testBundleSlot_card (Nat.le_of_lt hj))

abbrev TestFreshRank (m R j : ℕ) := testMultiplicity m R (j+1) (Fin.last (j+1))

abbrev TestFreshCoordinates (m R j : ℕ) (hj : j<R) :=
  FiniteCoordinateBundle (stageProjectiveDimensions m R (j+1) hj)
    (fun _ : Fin (TestFreshRank m R j) => some (Fin.last j))
    (TestFreshRank m R j) (Fintype.card_fin _)

theorem exists_test_eight_fresh_bundle_maps {m R j : ℕ} (hm : 0<m) (hj : j<R) :
    ∃ T : Fin 8 → ∀ y, TestSourceCoordinates m R j hj y →L[ℂ] TestFreshCoordinates m R j hj y,
      (∀ i, ContMDiff 𝓘(ℝ,SmoothPrefixModel m R j hj)
        (𝓘(ℝ,SmoothPrefixModel m R j hj).prod
          𝓘(ℝ,(Fin (testRank m R j) → ℂ) →L[ℝ] (Fin (TestFreshRank m R j) → ℂ))) ∞
        (fun y => TotalSpace.mk' ((Fin (testRank m R j) → ℂ) →L[ℝ]
          (Fin (TestFreshRank m R j) → ℂ)) y ((T i y).restrictScalars ℝ))) ∧
      ∀ y (S : Submodule ℂ (TestSourceCoordinates m R j hj y)), m<finrank ℂ S →
        2*finrank ℂ S≤finrank ℂ (⨆ i, S.map (T i y).toLinearMap :
          Submodule ℂ (TestFreshCoordinates m R j hj y)) := by
  apply Incidence.exists_eight_fresh_bundle_maps
  · unfold testRank
    positivity
  · exact testMultiplicity_fresh hj
  · exact smoothPrefix_incidence_margin hm hj

end Kaplansky

end

section
open Bundle Topology Module
namespace Kaplansky
open ComplexGrassmann

/-- The finite-coordinate incidence maps give genuine continuous maps on
the original Hilbert-sum presentation of E_j and its fresh block. -/
theorem exists_smoothTest_freshMaps {m R j : ℕ} (hm : 0<m) (hj : j<R) :
    ∃ A : ∀ y, Fin 8 → SmoothTestBundle m R (j+1) j hj (Nat.le_succ j) y →ₗ[ℂ]
      (smoothFreshCore m R j hj).Fiber y,
      (∀ i, Continuous (fun z : TotalSpace (EuclideanSpace ℂ (TestBundleSlot m R j))
        (SmoothTestBundle m R (j+1) j hj (Nat.le_succ j)) =>
        TotalSpace.mk' (EuclideanSpace ℂ (Fin (TestFreshRank m R j))) z.proj (A z.proj i z.2))) ∧
      ∀ y (S : Submodule ℂ (SmoothTestBundle m R (j+1) j hj (Nat.le_succ j) y)),
        m<finrank ℂ S → 2*finrank ℂ S≤finrank ℂ
          (⨆ i, S.map (A y i) : Submodule ℂ ((smoothFreshCore m R j hj).Fiber y)) := by
  obtain ⟨T,hT,hExp⟩ := exists_test_eight_fresh_bundle_maps hm hj
  let e := finiteCoordinateEquiv (testRank m R j) (testBundleSlot_card (Nat.le_of_lt hj) (m := m))
  let f := finiteCoordinateEquiv (TestFreshRank m R j) (Fintype.card_fin (TestFreshRank m R j))
  let a := fun y => (show SmoothTestBundle m R (j+1) j hj (Nat.le_succ j) y ≃ₗ[ℂ]
    TestSourceCoordinates m R j hj y from e.toLinearEquiv)
  let b := fun y => (show (smoothFreshCore m R j hj).Fiber y ≃ₗ[ℂ]
    TestFreshCoordinates m R j hj y from f.toLinearEquiv)
  let A := fun y i => (b y).symm.toLinearMap.comp ((T i y).toLinearMap.comp (a y).toLinearMap)
  refine ⟨A,?_,?_⟩
  · intro i
    have hc : Continuous (fun z : TotalSpace (Fin (testRank m R j) → ℂ) (TestSourceCoordinates m R j hj) =>
        TotalSpace.mk' (Fin (TestFreshRank m R j) → ℂ) z.proj (T i z.proj z.2)) :=
      ((hT i).continuous.comp (FiberBundle.continuous_proj _ _)).clm_bundle_apply continuous_id
    let H := finiteCoordinateTotalHomeomorph (stageProjectiveDimensions m R (j+1) hj)
      (fun s : TestBundleSlot m R j => testSummandLineIndex (Nat.le_succ j) s.1)
      (testRank m R j) (testBundleSlot_card (Nat.le_of_lt hj))
    let G := finiteCoordinateTotalHomeomorph (stageProjectiveDimensions m R (j+1) hj)
      (fun _ : Fin (TestFreshRank m R j) => some (Fin.last j))
      (TestFreshRank m R j) (Fintype.card_fin _)
    exact G.symm.continuous.comp (hc.comp H.continuous)
  · intro y S hS
    have h := hExp y (S.map (a y).toLinearMap) (by simpa only [(a y).finrank_map_eq] using hS)
    rw [(a y).finrank_map_eq] at h
    have he : (⨆ i, S.map (A y i)) =
        (⨆ i, (S.map (a y).toLinearMap).map (T i y).toLinearMap).map (b y).symm.toLinearMap := by
      rw [Submodule.map_iSup]
      apply iSup_congr
      intro i
      rw [Submodule.map_comp,Submodule.map_comp]
    rw [he,(b y).symm.finrank_map_eq]
    exact h

end Kaplansky

end

open Bundle Topology
namespace Kaplansky
open ComplexGrassmann

abbrev TestNextSlot (m R j : ℕ) :=
  (Σ i : Fin (j+1), Fin (testReplacementMultiplicity m R j i)) ⊕ Fin (TestFreshRank m R j)

def testNextLabel (m R j : ℕ) : TestNextSlot m R j → Option (Fin (j+1)) :=
  Sum.elim (fun s => testSummandLineIndex (Nat.le_succ j) s.1) (fun _ => some (Fin.last j))

/-- E_{j+1} presented as the direct sum of its replacement and fresh blocks. -/
def smoothNextCore (m R j : ℕ) (hj : j<R) :=
  smoothLineSumCore (stageProjectiveDimensions m R (j+1) hj) (testNextLabel m R j)

theorem testNextSlot_card {m R j : ℕ} (hj : j<R) :
    Fintype.card (TestNextSlot m R j) = testRank m R (j+1) := by
  have h := sum_testMultiplicity (m := m) hj
  rw [Fin.sum_univ_castSucc] at h
  change Fintype.card ((Σ i : Fin (j+1), Fin (testReplacementMultiplicity m R j i)) ⊕
    Fin (TestFreshRank m R j)) = _
  rw [Fintype.card_sum, Fintype.card_sigma]
  calc
    _ = (∑ i : Fin (j+1), testReplacementMultiplicity m R j i) + TestFreshRank m R j := by
      apply congrArg₂ (fun a b : ℕ => a + b)
      · exact Finset.sum_congr rfl (fun i _ => Fintype.card_fin _)
      · exact Fintype.card_fin _
    _ = _ := h

theorem exists_test_twentyFour_expanding_maps {m R j : ℕ} (hm : 0<m) (hj : j<R) :
    ∃ T : ∀ y, Fin 24 → SmoothTestBundle m R (j+1) j hj (Nat.le_succ j) y →ₗ[ℂ]
      (smoothNextCore m R j hj).Fiber y,
      (∀ i, Continuous (fun z : TotalSpace (EuclideanSpace ℂ (TestBundleSlot m R j))
        (SmoothTestBundle m R (j+1) j hj (Nat.le_succ j)) =>
        TotalSpace.mk' (EuclideanSpace ℂ (TestNextSlot m R j)) z.proj (T z.proj i z.2))) ∧
      ∀ y, IntrinsicExpanding (T y) := by
  obtain ⟨A,hA,heA⟩ := exists_smoothTest_replacements hm hj
  obtain ⟨B,hB,heB⟩ := exists_smoothTest_freshMaps hm hj
  let L := fun u : TestNextSlot m R j =>
    productLineCore (stageProjectiveDimensions m R (j+1) hj) (testNextLabel m R j u)
  let T : ∀ y, Fin 24 → SmoothTestBundle m R (j+1) j hj (Nat.le_succ j) y →ₗ[ℂ]
      (smoothNextCore m R j hj).Fiber y := fun y q => Fin.addCases
    (motive := fun _ : Fin (16+8) => SmoothTestBundle m R (j+1) j hj (Nat.le_succ j) y →ₗ[ℂ] (smoothNextCore m R j hj).Fiber y)
    (fun i => (lineSumInl L y).comp (A y i))
    (fun i => (lineSumInr L y).comp (B y i)) q
  refine ⟨T,?_,?_⟩
  · intro i
    refine Fin.addCases (m := 16) (n := 8) ?_ ?_ i
    · intro a
      have ht (y) : T y (Fin.castAdd 8 a) = (lineSumInl L y).comp (A y a) :=
        Fin.addCases_left a
      apply ((continuous_lineSumInl L).comp (hA a)).congr
      intro z
      apply congrArg (TotalSpace.mk' _ z.proj)
      exact (congrArg (fun F => F z.2) (ht z.proj)).symm
    · intro b
      have ht (y) : T y (Fin.natAdd 16 b) = (lineSumInr L y).comp (B y b) :=
        Fin.addCases_right b
      apply ((continuous_lineSumInr L).comp (hB b)).congr
      intro z
      apply congrArg (TotalSpace.mk' _ z.proj)
      exact (congrArg (fun F => F z.2) (ht z.proj)).symm
  · intro y
    let : FiniteDimensional ℂ ((finiteLineSumCore L).Fiber y) :=
      inferInstanceAs (FiniteDimensional ℂ (EuclideanSpace ℂ (TestNextSlot m R j)))
    exact combined_expanding m (A y) (B y) (lineSumInl L y) (lineSumInr L y)
      (lineSumInl_injective L y) (lineSumInr_injective L y) (heA y) (heB y)

end Kaplansky

end

end OAI