OAI/CategoryTheory/Thomason/Simplicial/ExhaustionWeakEquivalence.lean

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52 declarations, 0 contain sorry, 0 declared as axioms

Every realization point has unique nondegenerate interior coordinates

  1. theorem OAI.Thomason.Construction.RealizationPrism.normalizeSimplex_fullSupport line 22
  2. theorem OAI.Thomason.Construction.RealizationPrism.normalizeSupported_fullSupport line 30
  3. theorem OAI.Thomason.Construction.RealizationPrism.normalization_fullSupport line 37

    Source documentation

    No coordinate of the intrinsic nondegenerate representative vanishes.

    theorem normalization_fullSupport (K : SSet.{0}) (x : SSet.toTop.obj K) :
        (normalization K x).2 ∈ fullSupport (normalization K x).1.dim := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.normalization, OAI.Thomason.Construction.RealizationPrism.fullSupport

  4. def OAI.Thomason.Construction.RealizationPrism.interiorCoordinatesEquiv line 45

    Source documentation

    The underlying set of a realization is the disjoint union of nondegenerate simplex interiors. This does not give the disjoint-union topology.

    def interiorCoordinatesEquiv (K : SSet.{0}) :
        SSet.toTop.obj K ≃ Σ s : K.N, fullSupport s.dim where
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.fullSupport

  5. theorem OAI.Thomason.Construction.RealizationPrism.standard_boundary_carrier_iff line 80

    Source documentation

    A supported simplex of the standard simplex belongs to its boundary precisely when some original barycentric coordinate vanishes.

    theorem standard_boundary_carrier_iff (n : ℕ) (x : StdSimplex ℝ (Fin (n+1))) :
        simplexCarrier (Δ[n] : SSet.{0}) (SSet.yonedaEquiv (𝟙 _)) x ≤ SSet.boundary n ↔
          ∃ i, x.weights i = 0 := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.simplexCarrier

  6. theorem OAI.Thomason.Construction.RealizationPrism.standard_boundary_point_iff line 105

    Source documentation

    The actual realized boundary has exactly the familiar zero-coordinate locus.

    theorem standard_boundary_point_iff (n : ℕ) (x : StdSimplex ℝ (Fin (n+1))) :
        simplexPoint (Δ[n] : SSet.{0}) (SSet.yonedaEquiv (𝟙 _)) x ∈
            Set.range (SSet.toTop.map (SSet.boundary n).ι).hom ↔
          ∃ i, x.weights i = 0 := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.simplexPoint

  7. theorem OAI.Thomason.Construction.RealizationPrism.simplexPoint_standard_id line 130

    Source documentation

    The parameter map of the identity simplex is the inverse of the standard realization homeomorphism.

    theorem simplexPoint_standard_id (n : ℕ) (x : StdSimplex ℝ (Fin (n+1))) :
        simplexPoint (Δ[n] : SSet.{0}) (SSet.yonedaEquiv (𝟙 _)) x =
          (SimplexCategory.mk n).toTopHomeo.symm x := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.simplexPoint

  8. def OAI.Thomason.Construction.RealizationPrism.boundaryLocus line 143

    Source documentation

    The boundary locus, including the empty boundary in dimension zero.

    def boundaryLocus (n : ℕ) : Set (StdSimplex ℝ (Fin (n+1))) :=
    …
  9. def OAI.Thomason.Construction.RealizationPrism.boundaryCoordinates line 147

    Source documentation

    The barycentric coordinates of the actual boundary inclusion.

    def boundaryCoordinates (n : ℕ) :
        C(SSet.toTop.obj (SSet.boundary n : SSet.{0}), StdSimplex ℝ (Fin (n+1))) :=
    …
  10. theorem OAI.Thomason.Construction.RealizationPrism.boundaryCoordinates_isClosedEmbedding line 152
  11. theorem OAI.Thomason.Construction.RealizationPrism.range_boundaryCoordinates line 157
  12. def OAI.Thomason.Construction.RealizationPrism.boundaryHomeomorph line 177

    Source documentation

    The actual boundary realization is homeomorphic to the zero-coordinate locus of the barycentric simplex.

    def boundaryHomeomorph (n : ℕ) :
        SSet.toTop.obj (SSet.boundary n : SSet.{0}) ≃ₜ boundaryLocus n :=
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryLocus

  13. theorem OAI.Thomason.Construction.RealizationPrism.boundaryHomeomorph_inclusion line 184

    Source documentation

    The homeomorphism identifies the realized boundary arrow with the actual barycentric subspace inclusion, not just with an abstract homeomorphic pair.

    theorem boundaryHomeomorph_inclusion (n : ℕ)
        (x : SSet.toTop.obj (SSet.boundary n : SSet.{0})) :
        (boundaryHomeomorph n x).val =
          (SimplexCategory.mk n).toTopHomeo
            ((SSet.toTop.map (SSet.boundary n).ι).hom x) := rfl
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryHomeomorph

  14. def OAI.Thomason.Construction.RealizationPrism.boundaryInclusion line 213

    Source documentation

    The literal inclusion of the barycentric boundary subspace.

    def boundaryInclusion (n : ℕ) :
        TopCat.of (boundaryLocus n) ⟶ TopCat.of (StdSimplex ℝ (Fin (n+1))) :=
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryLocus

  15. def OAI.Thomason.Construction.RealizationPrism.boundaryArrowIso line 218

    Source documentation

    The whole realized boundary arrow agrees with the barycentric pair.

    def boundaryArrowIso (n : ℕ) :
        Arrow.mk (SSet.toTop.map (SSet.boundary n).ι) ≅ Arrow.mk (boundaryInclusion n) :=
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryInclusion

  16. theorem OAI.Thomason.Construction.RealizationPrism.singular_boundary_lifting_iff line 229

    Source documentation

    Singular boundary filling is exactly lifting against the actual barycentric boundary inclusion.

    theorem singular_boundary_lifting_iff {X Y : TopCat.{0}} (p : X ⟶ Y) (n : ℕ) :
        HasLiftingProperty (SSet.boundary n).ι (TopCat.toSSet.map p) ↔
          HasLiftingProperty (boundaryInclusion n) p :=
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryInclusion

  17. theorem OAI.Thomason.Construction.RealizationPrism.singular_boundary_rlp_iff line 237

    Source documentation

    The entire simplicial boundary lifting class has this concrete topological interpretation.

    theorem singular_boundary_rlp_iff {X Y : TopCat.{0}} (p : X ⟶ Y) :
        I.rlp (TopCat.toSSet.map p) ↔ ∀ n, HasLiftingProperty (boundaryInclusion n) p := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryInclusion

  18. theorem OAI.Thomason.Construction.RealizationPrism.singular_weak_of_boundary_lifting line 248

    Source documentation

    Maps lifting against every barycentric boundary induce actual weak homotopy equivalences of singular realizations.

    theorem singular_weak_of_boundary_lifting {X Y : TopCat.{0}} (p : X ⟶ Y)
        (h : ∀ n, HasLiftingProperty (boundaryInclusion n) p) :
        realizationWeakEquivalences (TopCat.toSSet.map p) :=
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryInclusion, OAI.Thomason.Construction.realizationWeakEquivalences

  19. theorem OAI.Thomason.Construction.RealizationPrism.realization_mono_lifting line 256

    Source documentation

    Elementary barycentric boundary lifts extend over every realized simplicial monomorphism. This is the actual topological lifting property, obtained through the adjunction and the proved boundary generation theorem.

    theorem realization_mono_lifting {X Y : TopCat.{0}} (p : X ⟶ Y)
        (h : ∀ n, HasLiftingProperty (boundaryInclusion n) p)
        {K L : SSet.{0}} (i : K ⟶ L) [Mono i] :
        HasLiftingProperty (SSet.toTop.map i) p := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryInclusion

  20. def OAI.Thomason.Construction.RealizationPrism.relativeBoundaryExtension line 267

    Source documentation

    A concrete continuous extension preserving the prescribed map on a subcomplex and its image under p.

    def relativeBoundaryExtension {X Y : TopCat.{0}} (p : X ⟶ Y)
        (h : ∀ n, HasLiftingProperty (boundaryInclusion n) p)
        (K : SSet.{0}) (A : K.Subcomplex)
        (a : SSet.toTop.obj (A : SSet) ⟶ X) (b : SSet.toTop.obj K ⟶ Y)
        (sq : CommSq a (SSet.toTop.map A.ι) p b) : SSet.toTop.obj K ⟶ X := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryInclusion

  21. theorem OAI.Thomason.Construction.RealizationPrism.relativeBoundaryExtension_restrict line 276
  22. theorem OAI.Thomason.Construction.RealizationPrism.relativeBoundaryExtension_comp line 286
  23. theorem OAI.Thomason.Construction.RealizationPrism.simplexPoint_as_realized_map line 312
  24. theorem OAI.Thomason.Construction.RealizationPrism.boundaryLocus_eq_compl_fullSupport line 321
  25. def OAI.Thomason.Construction.RealizationPrism.cellBoundaryMap line 329

    Source documentation

    The actual attaching map is the realization of the simplicial boundary followed by the given characteristic simplex.

    def cellBoundaryMap (K : SSet.{0}) {n : ℕ} (s : K.obj (.op (.mk n))) :
        SSet.toTop.obj (SSet.boundary n : SSet.{0}) ⟶ SSet.toTop.obj K :=
    …
  26. theorem OAI.Thomason.Construction.RealizationPrism.cellBoundaryMap_coordinates line 333
  27. theorem OAI.Thomason.Construction.RealizationPrism.range_cellBoundaryMap line 346
  28. theorem OAI.Thomason.Construction.RealizationPrism.cell_boundary_eq_closure_diff line 355

    Source documentation

    The boundary image is exactly the part of the closed characteristic cell outside its own interior, allowing arbitrary identifications of faces.

    theorem cell_boundary_eq_closure_diff (K : SSet.{0}) (s : K.N) :
        Set.range (cellBoundaryMap K s.simplex).hom =
          closure (simplexPoint K s.simplex '' fullSupport s.dim) \
            (simplexPoint K s.simplex '' fullSupport s.dim) := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.cellBoundaryMap, OAI.Thomason.Construction.RealizationPrism.simplexPoint, OAI.Thomason.Construction.RealizationPrism.fullSupport

  29. theorem OAI.Thomason.Construction.RealizationPrism.carrier_interior line 392

    Source documentation

    An interior point has the whole characteristic simplex as its carrier.

    theorem carrier_interior (K : SSet.{0}) {n : ℕ} (s : K.obj (.op (.mk n)))
        (x : StdSimplex ℝ (Fin (n+1))) (hx : x ∈ fullSupport n) :
        carrier K (simplexPoint K s x) = SSet.Subcomplex.ofSimplex s := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.fullSupport, OAI.Thomason.Construction.RealizationPrism.carrier, OAI.Thomason.Construction.RealizationPrism.simplexPoint

  30. theorem OAI.Thomason.Construction.RealizationPrism.interior_mem_subcomplex_iff line 409

    Source documentation

    A subcomplex contains a point of a simplex interior exactly when it contains the simplex itself.

    theorem interior_mem_subcomplex_iff (K : SSet.{0}) (A : K.Subcomplex) {n : ℕ}
        (s : K.obj (.op (.mk n))) (x : StdSimplex ℝ (Fin (n+1))) (hx : x ∈ fullSupport n) :
        simplexPoint K s x ∈ Set.range (SSet.toTop.map A.ι).hom ↔ s ∈ A.obj _ := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.fullSupport, OAI.Thomason.Construction.RealizationPrism.simplexPoint

  31. theorem OAI.Thomason.Construction.RealizationPrism.boundary_point_dimension_lt line 417

    Source documentation

    Boundary points of an n-simplex belong to cells of strictly smaller dimension, including when the original simplex or its faces are degenerate.

    theorem boundary_point_dimension_lt (K : SSet.{0}) {n : ℕ}
        (s : K.obj (.op (.mk n))) (x : StdSimplex ℝ (Fin (n+1))) (hx : x ∈ boundaryLocus n) :
        (normalization K (simplexPoint K s x)).1.dim < n := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.boundaryLocus, OAI.Thomason.Construction.RealizationPrism.normalization, OAI.Thomason.Construction.RealizationPrism.simplexPoint

  32. theorem OAI.Thomason.Construction.RealizationPrism.cellBoundaryMap_dimension_lt line 428

    Source documentation

    The actual attaching map lands entirely in lower-dimensional cells.

    theorem cellBoundaryMap_dimension_lt (K : SSet.{0}) {n : ℕ}
        (s : K.obj (.op (.mk n)))
        (x : SSet.toTop.obj (SSet.boundary n : SSet.{0})) :
        (normalization K ((cellBoundaryMap K s).hom x)).1.dim < n := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.normalization, OAI.Thomason.Construction.RealizationPrism.cellBoundaryMap

  33. abbrev OAI.Thomason.Construction.RealizationPrism.simplicialBoundaryCell line 460
  34. abbrev OAI.Thomason.Construction.RealizationPrism.realizedBoundaryCell line 462
  35. abbrev OAI.Thomason.Construction.RealizationPrism.barycentricBoundaryCell line 464
  36. def OAI.Thomason.Construction.RealizationPrism.realizeBoundaryAttachment line 468

    Source documentation

    Realization carries a simultaneous simplicial boundary attachment to the corresponding simultaneous topological attachment.

    def realizeBoundaryAttachment {X Y : SSet.{0}} {n : ℕ} {f : X ⟶ Y}
        (c : AttachCells.{0} (simplicialBoundaryCell n) f) :
        AttachCells.{0} (realizedBoundaryCell n) (SSet.toTop.map f) where
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.simplicialBoundaryCell, OAI.Thomason.Construction.RealizationPrism.realizedBoundaryCell

  37. def OAI.Thomason.Construction.RealizationPrism.realizedCellComplexOfMono line 490

    Source documentation

    The topological skeletal presentation with the original realized boundary arrows.

    def realizedCellComplexOfMono {X Y : SSet.{0}} (i : X ⟶ Y) [Mono i] :
        RelativeCellComplex.{0} realizedBoundaryCell (SSet.toTop.map i) := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.realizedBoundaryCell

  38. def OAI.Thomason.Construction.RealizationPrism.barycentricCellComplexOfMono line 501

    Source documentation

    Every realized monomorphism is obtained by attaching actual barycentric n-simplices along their boundaries at stage n.

    def barycentricCellComplexOfMono {X Y : SSet.{0}} (i : X ⟶ Y) [Mono i] :
        RelativeCellComplex.{0} barycentricBoundaryCell (SSet.toTop.map i) where
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.barycentricBoundaryCell

  39. theorem OAI.Thomason.Construction.RealizationPrism.mem_range_iff_normalization line 527

    Source documentation

    Subcomplex membership can be tested on the unique nondegenerate interior representative of the point.

    theorem mem_range_iff_normalization (K : SSet.{0}) (A : K.Subcomplex)
        (x : SSet.toTop.obj K) :
        x ∈ Set.range (SSet.toTop.map A.ι).hom ↔
          (normalization K x).1.simplex ∈ A.obj _ := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.normalization

  40. theorem OAI.Thomason.Construction.RealizationPrism.range_iSup_inclusion line 540

    Source documentation

    Realization carries an arbitrary subcomplex union to the literal union of the corresponding topological subspaces.

    theorem range_iSup_inclusion (K : SSet.{0}) {ι : Type} (A : ι → K.Subcomplex) :
        Set.range (SSet.toTop.map (iSup A).ι).hom =
          ⋃ i, Set.range (SSet.toTop.map (A i).ι).hom := by
    …
  41. theorem OAI.Thomason.Construction.RealizationPrism.range_realized_map line 550

    Source documentation

    The actual point-set image of a realized simplicial map is exactly the realization of its simplicial image subcomplex.

    theorem range_realized_map {K L : SSet.{0}} (f : K ⟶ L) :
        Set.range (SSet.toTop.map f).hom =
          Set.range (SSet.toTop.map (SSet.Subcomplex.range f).ι).hom := by
    …
  42. theorem OAI.Thomason.Construction.RealizationPrism.compact_subset_stage line 585

    Source documentation

    A compact subset of an exhausted realization lies in one actual stage. The proof bounds its finitely many intrinsic carriers simultaneously.

    theorem compact_subset_stage (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤)
        (C : Set (SSet.toTop.obj K)) (hC : IsCompact C) :
        ∃ n, C ⊆ Set.range (SSet.toTop.map (A n).ι).hom := by
    …
  43. theorem OAI.Thomason.Construction.RealizationPrism.compact_map_factors_stage line 615

    Source documentation

    Every compact continuous map factors continuously through a single stage, with exact equality after the actual inclusion.

    theorem compact_map_factors_stage {P : Type} [TopologicalSpace P] [CompactSpace P]
        (K : SSet.{0}) (A : ℕ → K.Subcomplex) (hA : Monotone A) (hcover : iSup A = ⊤)
        (f : C(P, SSet.toTop.obj K)) :
        ∃ (n : ℕ) (g : C(P, SSet.toTop.obj (A n : SSet))),
          (SSet.toTop.map (A n).ι).hom.comp g = f := by
    …
  44. theorem OAI.Thomason.Construction.RealizationPrism.compact_map_factors_stage_after line 633

    Source documentation

    The stage can be chosen beyond any previously fixed stage.

    theorem compact_map_factors_stage_after {P : Type} [TopologicalSpace P] [CompactSpace P]
        (K : SSet.{0}) (A : ℕ → K.Subcomplex) (hA : Monotone A) (hcover : iSup A = ⊤)
        (m : ℕ) (f : C(P, SSet.toTop.obj K)) :
        ∃ (n : ℕ), m ≤ n ∧ ∃ g : C(P, SSet.toTop.obj (A n : SSet)),
          (SSet.toTop.map (A n).ι).hom.comp g = f := by
    …
  45. theorem OAI.Thomason.Construction.RealizationPrism.compact_pair_factors_stage line 651

    Source documentation

    Two compact maps with unrelated domains have a common stage. This also synchronizes point representatives of different path components.

    theorem compact_pair_factors_stage {P Q : Type}
        [TopologicalSpace P] [CompactSpace P] [TopologicalSpace Q] [CompactSpace Q]
        (K : SSet.{0}) (A : ℕ → K.Subcomplex) (hA : Monotone A) (hcover : iSup A = ⊤)
        (f : C(P, SSet.toTop.obj K)) (g : C(Q, SSet.toTop.obj K)) :
        ∃ (n : ℕ) (f' : C(P, SSet.toTop.obj (A n : SSet)))
          (g' : C(Q, SSet.toTop.obj (A n : SSet))),
          (SSet.toTop.map (A n).ι).hom.comp f' = f ∧
          (SSet.toTop.map (A n).ι).hom.comp g' = g := by
    …
  46. theorem OAI.Thomason.Construction.RealizationPrism.based_cube_factors_stage line 697

    Source documentation

    A based cube whose basepoint is already in one stage lifts to a later stage with that same basepoint and its entire boundary fixed.

    theorem based_cube_factors_stage (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤) (m : ℕ)
        (x : SSet.toTop.obj (A m : SSet)) (d : ℕ)
        (p : GenLoop (Fin d) (SSet.toTop.obj K) ((SSet.toTop.map (A m).ι).hom x)) :
        ∃ (n : ℕ) (hn : m ≤ n),
          ∃ q : GenLoop (Fin d) (SSet.toTop.obj (A n : SSet))
            ((SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom x),
            ∀ t, (SSet.toTop.map (A n).ι).hom (q t) = p t := by
    …
  47. theorem OAI.Thomason.Construction.RealizationPrism.based_homotopy_factors_stage line 719

    Source documentation

    A homotopy between two cubes in one stage is already a homotopy in a later stage, with the original endpoint cubes and whole boundary retained.

    theorem based_homotopy_factors_stage (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤) (m : ℕ)
        (x : SSet.toTop.obj (A m : SSet)) (d : ℕ)
        (p q : GenLoop (Fin d) (SSet.toTop.obj (A m : SSet)) x)
        (H : (HomotopyMaps.loopMap (SSet.toTop.map (A m).ι).hom p).val.HomotopyRel
          (HomotopyMaps.loopMap (SSet.toTop.map (A m).ι).hom q).val (Cube.boundary (Fin d))) :
        ∃ (n : ℕ) (hn : m ≤ n),
          Nonempty ((HomotopyMaps.loopMap
            (SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom p).val.HomotopyRel
            (HomotopyMaps.loopMap
              (SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom q).val
            (Cube.boundary (Fin d))) := by
    …

    Mentions: OAI.Thomason.Construction.HomotopyMaps.loopMap

  48. theorem OAI.Thomason.Construction.RealizationPrism.homotopyGroup_eventual_eq line 753

    Source documentation

    Equality of homotopy classes in the exhausted realization is witnessed in one later stage, retaining the original chosen basepoint.

    theorem homotopyGroup_eventual_eq (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤) (m : ℕ)
        (x : SSet.toTop.obj (A m : SSet)) (d : ℕ)
        (a b : HomotopyGroup.Pi d (SSet.toTop.obj (A m : SSet)) x)
        (hab : HomotopyMaps.groupMap (SSet.toTop.map (A m).ι).hom d x a =
          HomotopyMaps.groupMap (SSet.toTop.map (A m).ι).hom d x b) :
        ∃ (n : ℕ) (hn : m ≤ n),
          HomotopyMaps.groupMap (SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom d x a =
          HomotopyMaps.groupMap (SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom d x b := by
    …

    Mentions: OAI.Thomason.Construction.HomotopyMaps.groupMap

  49. theorem OAI.Thomason.Construction.RealizationPrism.components_eventual_eq line 773

    Source documentation

    Equality of components also occurs at a finite stage.

    theorem components_eventual_eq (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤) (m : ℕ)
        (a b : ZerothHomotopy (SSet.toTop.obj (A m : SSet)))
        (hab : HomotopyMaps.componentsMap (SSet.toTop.map (A m).ι).hom a =
          HomotopyMaps.componentsMap (SSet.toTop.map (A m).ι).hom b) :
        ∃ (n : ℕ) (hn : m ≤ n),
          HomotopyMaps.componentsMap (SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom a =
          HomotopyMaps.componentsMap (SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom b := by
    …

    Mentions: OAI.Thomason.Construction.HomotopyMaps.componentsMap

  50. theorem OAI.Thomason.Construction.RealizationPrism.based_pair_factors_stage line 807

    Source documentation

    A pair of based cubes can be placed in the same stage, beyond the stage of their specified basepoint. Both cubes retain their entire boundary.

    theorem based_pair_factors_stage (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤) (m : ℕ)
        (x : SSet.toTop.obj (A m : SSet)) (d : ℕ)
        (p q : GenLoop (Fin d) (SSet.toTop.obj K) ((SSet.toTop.map (A m).ι).hom x)) :
        ∃ (n : ℕ) (hn : m ≤ n),
          ∃ p' q' : GenLoop (Fin d) (SSet.toTop.obj (A n : SSet))
            ((SSet.toTop.map (SSet.Subcomplex.homOfLE (hA hn))).hom x),
            (∀ t, (SSet.toTop.map (A n).ι).hom (p' t) = p t) ∧
            (∀ t, (SSet.toTop.map (A n).ι).hom (q' t) = q t) := by
    …
  51. theorem OAI.Thomason.Construction.RealizationPrism.exhaustion_initial_weak line 868

    Source documentation

    If the inclusion of the initial stage into every stage is weak, then its inclusion into the exhausted realization is weak. Compact cubes and relative homotopies provide the required finite-stage witnesses.

    theorem exhaustion_initial_weak (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤)
        (hW : ∀ n, realizationWeakEquivalences
          (SSet.Subcomplex.homOfLE (hA (Nat.zero_le n)))) :
        realizationWeakEquivalences (A 0).ι := by
    …

    Mentions: OAI.Thomason.Construction.realizationWeakEquivalences

  52. theorem OAI.Thomason.Construction.RealizationPrism.exhaustion_weak_of_successor line 946

    Source documentation

    Successive weak inclusions in a simplicial exhaustion induce a weak inclusion of its initial stage into the whole realization.

    theorem exhaustion_weak_of_successor (K : SSet.{0}) (A : ℕ → K.Subcomplex)
        (hA : Monotone A) (hcover : iSup A = ⊤)
        (hW : ∀ n, realizationWeakEquivalences
          (SSet.Subcomplex.homOfLE (hA (Nat.le_succ n)))) :
        realizationWeakEquivalences (A 0).ι := by
    …

    Mentions: OAI.Thomason.Construction.realizationWeakEquivalences