OAI/AlgebraicTopology/IntegralHomology/Obstruction.lean

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16 declarations, 0 contain sorry, 0 declared as axioms

Survival of hyperplane fiber classes and nonvanishing Thom obstructions.

  1. theorem OAI.Kaplansky.graphBundleChartNormalization_isIso line 17
  2. theorem OAI.Kaplansky.graphBundleChartToAmbient_mono line 28

    Source documentation

    Every graph-chart fiber class survives inclusion into the whole actual bundle pair in fiber degree. The global normalization provides a left inverse up to the proved local isomorphism.

    theorem graphBundleChartToAmbient_mono (F : ∀ i, GraphFrame 1 (K i))
        (hp : 0 < ∑ i, K i) :
        Mono (restrictedPairToAmbientHomologyMap (graphBundleChartDomain K F)
          nonzeroBundle (2*(∑ i, K i))) := by
    …

    Mentions: OAI.Kaplansky.restrictedPairToAmbientHomologyMap, OAI.Kaplansky.graphBundleChartDomain, OAI.Kaplansky.nonzeroBundle

  3. theorem OAI.Kaplansky.canonicalFiberGenerator_whole_ne_zero line 42

    Source documentation

    The original, preserved integral fiber generator has nonzero image in the whole hyperplane bundle. No choice of a new generator is involved.

    theorem canonicalFiberGenerator_whole_ne_zero (hp : 0 < ∑ i, K i) :
        canonicalWholeBundleFiberMap K (2*(∑ i, K i)) (canonicalFiberGenerator K hp) ≠ 0 := by
    …

    Mentions: OAI.Kaplansky.canonicalWholeBundleFiberMap, OAI.Kaplansky.canonicalFiberGenerator

  4. theorem OAI.Kaplansky.canonicalNormalizedOverlapGenerator_punctured_ne_zero line 56

    Source documentation

    The exact dependency recorded in Preserve376: the specified primitive overlap generator survives the ACTUAL punctured-bundle map.

    theorem canonicalNormalizedOverlapGenerator_punctured_ne_zero (hp : 0 < ∑ i, K i) :
        canonicalOverlapPuncturedMap K (2*(∑ i, K i))
          (canonicalNormalizedOverlapGenerator K hp) ≠ 0 :=
    …

    Mentions: OAI.Kaplansky.canonicalOverlapPuncturedMap, OAI.Kaplansky.canonicalNormalizedOverlapGenerator

  5. theorem OAI.Kaplansky.canonicalProductOrdinaryRelativeGenerator_ne_zero line 62
  6. theorem OAI.Kaplansky.canonicalProductRelativeGenerator_ne_zero line 68
  7. theorem OAI.Kaplansky.canonicalProductHomology_fundamental_ne_zero line 76

    Source documentation

    The canonical section sends the preserved integral fundamental class to a nonzero absolute homology class of the actual compactification.

    theorem canonicalProductHomology_fundamental_ne_zero (hp : 0 < ∑ i, K i) :
        canonicalProductHomologyMap K (2*(∑ i, K i))
          (projectiveProductFundamentalClass K hp) ≠ 0 := by
    …

    Mentions: OAI.Kaplansky.canonicalProductHomologyMap, OAI.Kaplansky.projectiveProductFundamentalClass

  8. theorem OAI.Kaplansky.canonicalProductHomologyMap_ne_zero line 89
  9. theorem OAI.Kaplansky.hyperplaneProduct_sectionHomology_ne_zero line 105

    Source documentation

    Every continuous section of the actual hyperplane sum induces a nonzero homology map in degree 2 sum(K), including degenerate sections.

    theorem hyperplaneProduct_sectionHomology_ne_zero (hp : 0 < ∑ i, K i)
        (s : ∀ y, (hyperplaneProductStage K).Fiber y)
        (hs : Continuous (fun y => TotalSpace.mk' (hyperplaneProductStage K).Model y (s y))) :
        sectionHomologyMap s hs (2*(∑ i, K i)) ≠ 0 := by
    …

    Mentions: OAI.Kaplansky.hyperplaneProductStage, OAI.Kaplansky.sectionHomologyMap

  10. theorem OAI.Kaplansky.hyperplaneProduct_every_section_has_zero line 114

    Source documentation

    A genuine section obstruction for H, the rank-sum(K) hyperplane sum. It makes no assertion about H with additional trivial summands.

    theorem hyperplaneProduct_every_section_has_zero (hp : 0 < ∑ i, K i)
        (s : ∀ y, (hyperplaneProductStage K).Fiber y)
        (hs : Continuous (fun y => TotalSpace.mk' (hyperplaneProductStage K).Model y (s y))) :
        ∃ y, s y = 0 := by
    …

    Mentions: OAI.Kaplansky.hyperplaneProductStage

  11. theorem OAI.Kaplansky.hyperplaneProduct_no_positive_frame line 123
  12. theorem OAI.Kaplansky.hyperplaneProduct_transported_sectionHomology_ne_zero line 132

    Source documentation

    Nonvanishing survives an actual total-space homeomorphism carrying a section to a section, by the already proved compactification naturality.

    theorem hyperplaneProduct_transported_sectionHomology_ne_zero
        {W : Type} [NormedAddCommGroup W] [NormedSpace ℂ W]
        {E : ProjectiveProduct K → Type}
        [∀ y, NormedAddCommGroup (E y)] [∀ y, NormedSpace ℂ (E y)]
        [TopologicalSpace (TotalSpace W E)] [FiberBundle W E] [VectorBundle ℂ W E]
        (hp : 0 < ∑ i, K i)
        (e : TotalSpace (hyperplaneProductStage K).Model (hyperplaneProductStage K).Fiber ≃ₜ TotalSpace W E)
        (t : ∀ y, E y) (ht : Continuous (fun y => TotalSpace.mk' W y (t y)))
        (he : ∀ y, e (TotalSpace.mk' (hyperplaneProductStage K).Model y (hyperplaneProductSection K y)) =
          TotalSpace.mk' W y (t y)) :
        sectionHomologyMap t ht (2*(∑ i, K i)) ≠ 0 :=
    …

    Mentions: OAI.Kaplansky.hyperplaneProductStage, OAI.Kaplansky.hyperplaneProductSection, OAI.Kaplansky.sectionHomologyMap

  13. theorem OAI.Kaplansky.hyperplaneThomZeroHomologyMap_ne_zero line 156

    Source documentation

    Nonvanishing in the genuine disk/sphere Thom quotient, with no assumed Thom class or characteristic-class identification.

    theorem hyperplaneThomZeroHomologyMap_ne_zero (hp : 0 < ∑ i, K i) :
        thomZeroHomologyMap (hyperplaneProductStage K) (2*(∑ i, K i)) ≠ 0 := by
    …

    Mentions: OAI.Kaplansky.thomZeroHomologyMap, OAI.Kaplansky.hyperplaneProductStage

  14. theorem OAI.Kaplansky.retainedTest_hyperplaneDegree_pos line 167
  15. theorem OAI.Kaplansky.retainedTest_hyperplaneThom_ne_zero line 172
  16. theorem OAI.Kaplansky.retainedTest_hyperplane_every_section_has_zero line 177