OAI/CategoryTheory/Thomason/Simplicial/KanSimplexContinuousFibers.lean

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47 declarations, 0 contain sorry, 0 declared as axioms

Exact finite cubical families in the original Kan total space

  1. theorem OAI.Thomason.Construction.RealizedCube.finite_kan_cube_family_lift line 30

    Source documentation

    With finite source, the entire exact higher family and its two given faces live in a single finite subcomplex of the original total space.

    theorem finite_kan_cube_family_lift {A K E B : SSet.{0}} [K.Finite]
        (i : A ⟶ K) [Mono i] (p : E ⟶ B) [HomotopicalAlgebra.Fibration p]
        (n : ℕ) (f : K ⟶ E) (h : A ⊗ (obj n) ⟶ E)
        (b : K ⊗ (obj n) ⟶ B)
        (h₀ : productChosenVertex A (initialVertex n) ≫ h = i ≫ f)
        (hb : h ≫ p = i ▷ (obj n) ≫ b)
        (hf : f ≫ p = productChosenVertex K (initialVertex n) ≫ b) :
        ∃ (S : E.Subcomplex) (_ : SSet.Finite S.toSSet)
          (eS : K ⊗ (obj n) ⟶ S.toSSet)
          (fS : K ⟶ S.toSSet) (hS : A ⊗ (obj n) ⟶ S.toSSet),
          fS ≫ S.ι = f ∧ hS ≫ S.ι = h ∧
          productChosenVertex K (initialVertex n) ≫ eS = fS ∧
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.productChosenVertex, OAI.Thomason.Construction.RealizedCube.initialVertex

  2. theorem OAI.Thomason.Construction.realizedHomotopy_over line 76

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    An exact simplicial homotopy over a base stays over that same base point at every real cylinder parameter.

    theorem realizedHomotopy_over {E F B : SSet.{0}} (p : E ⟶ B) (q : F ⟶ B)
        {f g : E ⟶ F} (H : SSet.Homotopy f g)
        (hH : H.h ≫ q = fst E Δ[1] ≫ p)
        (t : unitInterval) (x : SSet.toTop.obj E) :
        (SSet.toTop.map q).hom (RealizedCylinder.homotopy H (t,x)) =
          (SSet.toTop.map p).hom x := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCylinder.homotopy

  3. theorem OAI.Thomason.Construction.realizedFiberMap_weak line 92

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    Literal point fibres of a realized fibrewise simplicial homotopy equivalence are weakly equivalent at EVERY real base point.

    theorem realizedFiberMap_weak {E F B : SSet.{0}} (p : E ⟶ B) (q : F ⟶ B)
        (f : E ⟶ F) (g : F ⟶ E) (hf : f ≫ q = p) (hg : g ≫ p = q)
        (H : SSet.Homotopy (𝟙 E) (f ≫ g)) (K : SSet.Homotopy (𝟙 F) (g ≫ f))
        (hH : H.h ≫ p = fst E Δ[1] ≫ p)
        (hK : K.h ≫ q = fst F Δ[1] ≫ q) (b : SSet.toTop.obj B) :
        topologicalWeakEquivalences (continuousFiberMap (SSet.toTop.map p) (SSet.toTop.map q)
          b (SSet.toTop.map f) (by rw [← SSet.toTop.map_comp, hf])) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousFiberMap

  4. def OAI.Thomason.Construction.intervalEdge line 129

    Source documentation

    The nondegenerate edge of the simplicial interval, with its actual initial and final vertices.

    def intervalEdge : SSet.Edge (initialSimplexVertex 1) (finalSimplexVertex 1) :=
    …

    Mentions: OAI.Thomason.Construction.initialSimplexVertex, OAI.Thomason.Construction.finalSimplexVertex

  5. theorem OAI.Thomason.Construction.intervalEdge_time line 148

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    The canonical interval edge uses precisely the affine time coordinate of the realized cylinder.

    theorem intervalEdge_time (t : unitInterval) :
        PrismBarycentric.realizationTime.hom (RealizationPrism.edgePath intervalEdge t) = t := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.edgePath, OAI.Thomason.Construction.intervalEdge

  6. theorem OAI.Thomason.Construction.realizationTime_injective line 162

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    Affine time distinguishes all points in the realized interval.

    theorem realizationTime_injective : Function.Injective PrismBarycentric.realizationTime.hom := by
    …
  7. theorem OAI.Thomason.Construction.realizedCylinder_second line 170

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    Every point of the cylinder has the same interval coordinate as the canonical edge at that time.

    theorem realizedCylinder_second {K : SSet.{0}} (x : SSet.toTop.obj K) (t : unitInterval) :
        (SSet.toTop.map (snd K (Δ[1] : SSet.{0}))).hom ((RealizedCylinder.comparison K).hom (x,t)) =
          RealizationPrism.edgePath intervalEdge t := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCylinder.comparison, OAI.Thomason.Construction.RealizationPrism.edgePath, OAI.Thomason.Construction.intervalEdge

  8. def OAI.Thomason.Construction.realizedIntervalPath line 177

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    The path realized by a base interval, with the exact image vertices.

    def realizedIntervalPath {B : SSet.{0}} (g : (Δ[1] : SSet.{0}) ⟶ B) :
        Path (RealizationPrism.vertexPoint B (g.app _ (initialSimplexVertex 1)))
          (RealizationPrism.vertexPoint B (g.app _ (finalSimplexVertex 1))) :=
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.vertexPoint, OAI.Thomason.Construction.initialSimplexVertex, OAI.Thomason.Construction.finalSimplexVertex

  9. theorem OAI.Thomason.Construction.realized_interval_homotopy_projection line 185

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    A simplicial cylinder lying exactly over the base interval realizes to a continuous lift of that same parametrized path.

    theorem realized_interval_homotopy_projection {K E B : SSet.{0}}
        (p : E ⟶ B) (g : (Δ[1] : SSet.{0}) ⟶ B) {f h : K ⟶ E}
        (H : SSet.Homotopy f h) (hH : H.h ≫ p = snd K Δ[1] ≫ g)
        (t : unitInterval) (x : SSet.toTop.obj K) :
        (SSet.toTop.map p).hom (RealizedCylinder.homotopy H (t,x)) = realizedIntervalPath g t := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCylinder.homotopy, OAI.Thomason.Construction.realizedIntervalPath

  10. theorem OAI.Thomason.Construction.realizedPointFiber_projection line 218

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    The realized point-fibre inclusion has exactly the specified constant image.

    theorem realizedPointFiber_projection {E B : SSet.{0}} (p : E ⟶ B) (b : B _⦋0⦌)
        (z : SSet.toTop.obj (simplicialPointFiber p b).toSSet) :
        (SSet.toTop.map p).hom ((SSet.toTop.map (simplicialPointFiber p b).ι).hom z) =
          RealizationPrism.vertexPoint B b := by
    …

    Mentions: OAI.Thomason.Construction.simplicialPointFiber, OAI.Thomason.Construction.RealizationPrism.vertexPoint

  11. def OAI.Thomason.Construction.realizedPointFiberComparison line 228

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    The canonical comparison attaches the constant path at the specified vertex. No preservation of pullbacks by realization is assumed.

    def realizedPointFiberComparison {E B : SSet.{0}} (p : E ⟶ B) (b : B _⦋0⦌) :
        SSet.toTop.obj (simplicialPointFiber p b).toSSet ⟶
          continuousHomotopyFiber (SSet.toTop.map p) (RealizationPrism.vertexPoint B b) :=
    …

    Mentions: OAI.Thomason.Construction.simplicialPointFiber, OAI.Thomason.Construction.continuousHomotopyFiber, OAI.Thomason.Construction.RealizationPrism.vertexPoint

  12. theorem OAI.Thomason.Construction.realizedPointFiberComparison_retraction line 241
  13. theorem OAI.Thomason.Construction.kan_simplex_realizedPointFiberComparison_weak line 250

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    For any Kan fibration over a standard simplex, the actual point-fibre comparison is a weak equivalence. This is the local geometric homotopy-fibre statement, proved independently of general acyclic Kan lifting.

    theorem kan_simplex_realizedPointFiberComparison_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ (Δ[n] : SSet.{0})) [HomotopicalAlgebra.Fibration p]
        (b : (Δ[n] : SSet.{0}) _⦋0⦌) :
        topologicalWeakEquivalences (realizedPointFiberComparison p b) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.realizedPointFiberComparison

  14. def OAI.Thomason.Construction.realizedFiberAlongInterval line 282

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    Attach the actual realized base edge to the initial point fibre.

    def realizedFiberAlongInterval {E B : SSet.{0}} (p : E ⟶ B)
        (g : (Δ[1] : SSet.{0}) ⟶ B) :
        SSet.toTop.obj (simplicialPointFiber p (g.app _ (initialSimplexVertex 1))).toSSet ⟶
          continuousHomotopyFiber (SSet.toTop.map p)
            (RealizationPrism.vertexPoint B (g.app _ (finalSimplexVertex 1))) :=
    …

    Mentions: OAI.Thomason.Construction.simplicialPointFiber, OAI.Thomason.Construction.initialSimplexVertex, OAI.Thomason.Construction.continuousHomotopyFiber, OAI.Thomason.Construction.RealizationPrism.vertexPoint, OAI.Thomason.Construction.finalSimplexVertex

  15. theorem OAI.Thomason.Construction.kan_transport_homotopy_fiber line 295

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    The weak simplicial transport furnished by the Kan lifting property commutes, by a constructed continuous homotopy, with the actual comparison to the terminal homotopy fibre. The homotopy retains the prescribed base edge and the remaining-path coordinate.

    theorem kan_transport_homotopy_fiber {E B : SSet.{0}} (p : E ⟶ B)
        [HomotopicalAlgebra.Fibration p] (g : (Δ[1] : SSet.{0}) ⟶ B) :
        ∃ t : (simplicialPointFiber p (g.app _ (initialSimplexVertex 1))).toSSet ⟶
            (simplicialPointFiber p (g.app _ (finalSimplexVertex 1))).toSSet,
          realizationWeakEquivalences t ∧
          Nonempty ((realizedFiberAlongInterval p g).hom.Homotopy
            (SSet.toTop.map t ≫ realizedPointFiberComparison p (g.app _ (finalSimplexVertex 1))).hom) := by
    …

    Mentions: OAI.Thomason.Construction.simplicialPointFiber, OAI.Thomason.Construction.initialSimplexVertex, OAI.Thomason.Construction.finalSimplexVertex, OAI.Thomason.Construction.realizationWeakEquivalences, OAI.Thomason.Construction.realizedFiberAlongInterval, OAI.Thomason.Construction.realizedPointFiberComparison

  16. theorem OAI.Thomason.Construction.kan_transport_homotopy_fiber_weak_iff line 331

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    Weakness of the canonical comparison is detected after transporting any neighbouring fibre along its actual base edge. This uses all homotopy groups, with no global fibration-realization theorem assumed.

    theorem kan_transport_homotopy_fiber_weak_iff {E B : SSet.{0}} (p : E ⟶ B)
        [HomotopicalAlgebra.Fibration p] (g : (Δ[1] : SSet.{0}) ⟶ B) :
        topologicalWeakEquivalences (realizedFiberAlongInterval p g) ↔
          topologicalWeakEquivalences
            (realizedPointFiberComparison p (g.app _ (finalSimplexVertex 1))) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.realizedFiberAlongInterval, OAI.Thomason.Construction.realizedPointFiberComparison, OAI.Thomason.Construction.finalSimplexVertex

  17. def OAI.Thomason.Construction.homotopyFiberFromPathHomotopy line 360

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    Homotopic chosen paths produce homotopic maps from a fixed point fibre into the actual terminal homotopy fibre.

    def homotopyFiberFromPathHomotopy {A E B : TopCat.{0}} (p : E ⟶ B) (f : A ⟶ E)
        {x y : B} {γ δ : Path x y} (H : γ.Homotopy δ) (hf : ∀ a, p.hom (f.hom a) = x) :
        (homotopyFiberFromPath p f γ hf).hom.Homotopy
          (homotopyFiberFromPath p f δ hf).hom where
    …

    Mentions: OAI.Thomason.Construction.homotopyFiberFromPath

  18. theorem OAI.Thomason.Construction.realizedFiberAlongInterval_append line 386

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    The exact comparison with a transported point fibre agrees with appending the base path, up to the canonical left-unit homotopy.

    theorem realizedFiberAlongInterval_append {E B : SSet.{0}} (p : E ⟶ B)
        (g : (Δ[1] : SSet.{0}) ⟶ B) :
        Nonempty ((realizedPointFiberComparison p (g.app _ (initialSimplexVertex 1)) ≫
          homotopyFiberPathTransport (SSet.toTop.map p) (realizedIntervalPath g)).hom.Homotopy
          (realizedFiberAlongInterval p g).hom) := by
    …

    Mentions: OAI.Thomason.Construction.realizedPointFiberComparison, OAI.Thomason.Construction.initialSimplexVertex, OAI.Thomason.Construction.homotopyFiberPathTransport, OAI.Thomason.Construction.realizedIntervalPath, OAI.Thomason.Construction.realizedFiberAlongInterval

  19. theorem OAI.Thomason.Construction.kan_fiber_comparison_weak_iff_of_interval line 407

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    For an arbitrary Kan fibration, the full actual weak-equivalence test for its point-fibre comparison is unchanged along a base interval.

    theorem kan_fiber_comparison_weak_iff_of_interval {E B : SSet.{0}} (p : E ⟶ B)
        [HomotopicalAlgebra.Fibration p] (g : (Δ[1] : SSet.{0}) ⟶ B) :
        topologicalWeakEquivalences
          (realizedPointFiberComparison p (g.app _ (initialSimplexVertex 1))) ↔
        topologicalWeakEquivalences
          (realizedPointFiberComparison p (g.app _ (finalSimplexVertex 1))) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.realizedPointFiberComparison, OAI.Thomason.Construction.initialSimplexVertex, OAI.Thomason.Construction.finalSimplexVertex

  20. theorem OAI.Thomason.Construction.kan_fiber_comparison_weak_iff_of_edge line 421

    Source documentation

    The same genuine comparison test is invariant along every simplicial edge, with its given endpoints.

    theorem kan_fiber_comparison_weak_iff_of_edge {E B : SSet.{0}} (p : E ⟶ B)
        [HomotopicalAlgebra.Fibration p] {x y : B _⦋0⦌} (e : SSet.Edge x y) :
        topologicalWeakEquivalences (realizedPointFiberComparison p x) ↔
          topologicalWeakEquivalences (realizedPointFiberComparison p y) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.realizedPointFiberComparison

  21. theorem OAI.Thomason.Construction.kan_fiber_comparison_weak_iff_of_realization_path line 454

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    The actual point-fibre/homotopy-fibre comparison is weak at one vertex if and only if it is weak at any vertex joined to it by a continuous path.

    theorem kan_fiber_comparison_weak_iff_of_realization_path {E B : SSet.{0}} (p : E ⟶ B)
        [HomotopicalAlgebra.Fibration p] {x y : B _⦋0⦌}
        (h : Path (RealizationPrism.vertexPoint B x) (RealizationPrism.vertexPoint B y)) :
        topologicalWeakEquivalences (realizedPointFiberComparison p x) ↔
          topologicalWeakEquivalences (realizedPointFiberComparison p y) := by
    …

    Mentions: OAI.Thomason.Construction.RealizationPrism.vertexPoint, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.realizedPointFiberComparison

  22. theorem OAI.Thomason.Construction.realizedVertexSubcomplex_range line 485
  23. def OAI.Thomason.Construction.realizedPointFiberHomeomorph line 503

    Source documentation

    Realization commutes homeomorphically with a fibre over a simplicial vertex, using the closed subcomplex embedding.

    def realizedPointFiberHomeomorph {E B : SSet.{0}} (p : E ⟶ B) (b : B _⦋0⦌) :
        SSet.toTop.obj (simplicialPointFiber p b).toSSet ≃ₜ
          {x : SSet.toTop.obj E // (SSet.toTop.map p).hom x = RealizationPrism.vertexPoint B b} :=
    …

    Mentions: OAI.Thomason.Construction.simplicialPointFiber, OAI.Thomason.Construction.RealizationPrism.vertexPoint

  24. theorem OAI.Thomason.Construction.realizedPointFiberHomeomorph_val line 513

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    The homeomorphism retains the original total-space point exactly.

    theorem realizedPointFiberHomeomorph_val {E B : SSet.{0}} (p : E ⟶ B) (b : B _⦋0⦌)
        (x : SSet.toTop.obj (simplicialPointFiber p b).toSSet) :
        (realizedPointFiberHomeomorph p b x).val =
          (SSet.toTop.map (simplicialPointFiber p b).ι).hom x := rfl

    Mentions: OAI.Thomason.Construction.simplicialPointFiber, OAI.Thomason.Construction.realizedPointFiberHomeomorph

  25. def OAI.Thomason.Construction.continuousPointFiberComparison line 520

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    The canonical map from the literal continuous point fibre into the homotopy fibre appends its constant path.

    def continuousPointFiberComparison {X Y : TopCat.{0}} (p : X ⟶ Y) (b : Y) :
        TopCat.of {x : X // p.hom x = b} ⟶ continuousHomotopyFiber p b :=
    …

    Mentions: OAI.Thomason.Construction.continuousHomotopyFiber

  26. theorem OAI.Thomason.Construction.realizedPointFiberComparison_homeomorph line 530

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    The two fibre comparisons commute exactly under the homeomorphism.

    theorem realizedPointFiberComparison_homeomorph {E B : SSet.{0}} (p : E ⟶ B)
        (b : B _⦋0⦌) :
        (TopCat.isoOfHomeo (realizedPointFiberHomeomorph p b)).hom ≫
          continuousPointFiberComparison (SSet.toTop.map p) (RealizationPrism.vertexPoint B b) =
            realizedPointFiberComparison p b := by
    …

    Mentions: OAI.Thomason.Construction.realizedPointFiberHomeomorph, OAI.Thomason.Construction.continuousPointFiberComparison, OAI.Thomason.Construction.RealizationPrism.vertexPoint, OAI.Thomason.Construction.realizedPointFiberComparison

  27. theorem OAI.Thomason.Construction.kan_simplex_continuousPointFiberComparison_weak line 544

    Source documentation

    At every vertex of a standard simplex, the realized Kan fibration is quasifibrant: its literal continuous fibre maps weakly to its homotopy fibre.

    theorem kan_simplex_continuousPointFiberComparison_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ (Δ[n] : SSet.{0})) [HomotopicalAlgebra.Fibration p]
        (b : (Δ[n] : SSet.{0}) _⦋0⦌) :
        topologicalWeakEquivalences
          (continuousPointFiberComparison (SSet.toTop.map p) (RealizationPrism.vertexPoint _ b)) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousPointFiberComparison, OAI.Thomason.Construction.RealizationPrism.vertexPoint

  28. theorem OAI.Thomason.Construction.continuousPointFiberComparison_naturality line 572

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    The constant-path comparison commutes exactly with every commutative square of continuous maps, including the full path coordinate.

    @[reassoc] theorem continuousPointFiberComparison_naturality {X Y A B : TopCat.{0}}
        (p : X ⟶ A) (q : Y ⟶ B) (f : X ⟶ Y) (g : A ⟶ B)
        (h : f ≫ q = p ≫ g) (b : A) :
        continuousFiberBaseChangeMap p q f g h b ≫
            continuousPointFiberComparison q (g.hom b) =
          continuousPointFiberComparison p b ≫ continuousHomotopyFiberMap p q f g h b := by
    …

    Mentions: OAI.Thomason.Construction.continuousFiberBaseChangeMap, OAI.Thomason.Construction.continuousPointFiberComparison, OAI.Thomason.Construction.continuousHomotopyFiberMap

  29. theorem OAI.Thomason.Construction.continuousFiberBaseChange_weak_iff_homotopyFiberMap line 592

    Source documentation

    If the two canonical comparisons are weak equivalences, a square induces a weak equivalence on literal fibres precisely when it does on homotopy fibres. This transports the actual weak-equivalence tests.

    theorem continuousFiberBaseChange_weak_iff_homotopyFiberMap {X Y A B : TopCat.{0}}
        (p : X ⟶ A) (q : Y ⟶ B) (f : X ⟶ Y) (g : A ⟶ B)
        (h : f ≫ q = p ≫ g) (b : A)
        (hp : topologicalWeakEquivalences (continuousPointFiberComparison p b))
        (hq : topologicalWeakEquivalences (continuousPointFiberComparison q (g.hom b))) :
        topologicalWeakEquivalences (continuousFiberBaseChangeMap p q f g h b) ↔
          topologicalWeakEquivalences (continuousHomotopyFiberMap p q f g h b) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousPointFiberComparison, OAI.Thomason.Construction.continuousFiberBaseChangeMap, OAI.Thomason.Construction.continuousHomotopyFiberMap

  30. theorem OAI.Thomason.Construction.RealizedCube.kan_realizedPointFiberComparison_weak line 631

    Source documentation

    The literal realized vertex fibre of a Kan fibration over a finite cube maps weakly to its genuine continuous homotopy fibre.

    theorem kan_realizedPointFiberComparison_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ obj n) [HomotopicalAlgebra.Fibration p] (b : (obj n) _⦋0⦌) :
        topologicalWeakEquivalences (realizedPointFiberComparison p b) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.realizedPointFiberComparison

  31. theorem OAI.Thomason.Construction.RealizedCube.kan_continuousPointFiberComparison_weak line 644

    Source documentation

    Under the constructed fibre homeomorphism, the comparison is exactly the ordinary continuous point-fibre map which appends a constant path.

    theorem kan_continuousPointFiberComparison_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ obj n) [HomotopicalAlgebra.Fibration p] (b : (obj n) _⦋0⦌) :
        topologicalWeakEquivalences
          (continuousPointFiberComparison (SSet.toTop.map p) (RealizationPrism.vertexPoint _ b)) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousPointFiberComparison, OAI.Thomason.Construction.RealizationPrism.vertexPoint

  32. theorem OAI.Thomason.Construction.RealizedCube.kan_baseChange_weak line 655

    Source documentation

    Every simplicial map between finite cubes preserves the total space of a Kan fibration up to the actual realization weak-equivalence test.

    theorem kan_baseChange_weak {E : SSet.{0}} (n m : ℕ)
        (p : E ⟶ obj n) [HomotopicalAlgebra.Fibration p] (g : obj m ⟶ obj n) :
        realizationWeakEquivalences (pullback.fst p g) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.realizationWeakEquivalences

  33. def OAI.Thomason.Construction.RealizedCube.homotopyFiberMap line 669

    Source documentation

    The actual map on continuous homotopy fibres induced by a cubical base change retains both point and path coordinates.

    def homotopyFiberMap {E : SSet.{0}} (n m : ℕ)
        (p : E ⟶ obj n) (g : obj m ⟶ obj n) (b : SSet.toTop.obj (obj m)) :
        continuousHomotopyFiber (SSet.toTop.map (pullback.snd p g)) b ⟶
          continuousHomotopyFiber (SSet.toTop.map p) ((SSet.toTop.map g).hom b) :=
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.continuousHomotopyFiber

  34. theorem OAI.Thomason.Construction.RealizedCube.homotopyFiberMap_weak line 678

    Source documentation

    Cubical base change commutes with the genuine continuous homotopy fibre by an actual weak equivalence.

    theorem homotopyFiberMap_weak {E : SSet.{0}} (n m : ℕ)
        (p : E ⟶ obj n) [HomotopicalAlgebra.Fibration p] (g : obj m ⟶ obj n)
        (b : SSet.toTop.obj (obj m)) :
        topologicalWeakEquivalences (homotopyFiberMap n m p g b) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.RealizedCube.homotopyFiberMap

  35. theorem OAI.Thomason.Construction.RealizedCube.realizedProductCubeFiberInclusion_weak line 707

    Source documentation

    The literal fibre inclusion of a realized product projection over any point of the cube is a weak equivalence.

    theorem realizedProductCubeFiberInclusion_weak (F : SSet.{0}) (n : ℕ)
        (b : SSet.toTop.obj (obj n)) :
        topologicalWeakEquivalences (continuousFiberInclusion
          (SSet.toTop.map (snd F (obj n))) b) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousFiberInclusion

  36. theorem OAI.Thomason.Construction.RealizedCube.kan_cube_continuousFiberInclusion_weak line 721

    Source documentation

    For a Kan fibration over a standard cube, EVERY literal continuous fibre includes by a weak equivalence. The point need not be a vertex.

    theorem kan_cube_continuousFiberInclusion_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ (obj n)) [HomotopicalAlgebra.Fibration p]
        (b : SSet.toTop.obj (obj n)) :
        topologicalWeakEquivalences (continuousFiberInclusion (SSet.toTop.map p) b) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousFiberInclusion

  37. theorem OAI.Thomason.Construction.RealizedCube.kan_cube_allPointFiberComparison_weak line 739

    Source documentation

    The canonical constant-path comparison from the literal continuous fibre to the actual homotopy fibre is weak at every point of a cube.

    theorem kan_cube_allPointFiberComparison_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ (obj n)) [HomotopicalAlgebra.Fibration p]
        (b : SSet.toTop.obj (obj n)) :
        topologicalWeakEquivalences (continuousPointFiberComparison (SSet.toTop.map p) b) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousPointFiberComparison

  38. theorem OAI.Thomason.Construction.RealizedCube.kan_cube_continuousFiberBaseChange_weak line 770

    Source documentation

    Restriction along any map of standard cubes induces a weak equivalence of the literal continuous fibres at every real point. This includes all faces, degeneracies, and their composites.

    theorem kan_cube_continuousFiberBaseChange_weak {E : SSet.{0}} (n m : ℕ)
        (p : E ⟶ (obj n)) [HomotopicalAlgebra.Fibration p]
        (g : (obj m) ⟶ obj n) (b : SSet.toTop.obj (obj m)) :
        topologicalWeakEquivalences (continuousFiberBaseChangeMap
          (SSet.toTop.map (pullback.snd p g)) (SSet.toTop.map p)
          (SSet.toTop.map (pullback.fst p g)) (SSet.toTop.map g)
          (by rw [← SSet.toTop.map_comp, pullback.condition, SSet.toTop.map_comp]) b) := by
    …

    Mentions: OAI.Thomason.Construction.RealizedCube.obj, OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousFiberBaseChangeMap

  39. def OAI.Thomason.Construction.continuousProductFiberHomeomorph line 803

    Source documentation

    The fibre of the ordinary second projection is canonically its first factor. This identification retains the literal subspace topology.

    def continuousProductFiberHomeomorph (X B : TopCat.{0}) (b : B) :
        continuousFiber (continuousProductProjection X B) b ≃ₜ X where
    …

    Mentions: OAI.Thomason.Construction.continuousFiber, OAI.Thomason.Construction.continuousProductProjection

  40. theorem OAI.Thomason.Construction.realizedFiniteContractedProductFiberInclusion_weak line 817

    Source documentation

    A stationary contraction of a finite simplicial base makes the inclusion of every literal fibre of the realized product weak, even at a point which is not a simplicial vertex.

    theorem realizedFiniteContractedProductFiberInclusion_weak
        (F B : SSet.{0}) [B.Finite] (v : B _⦋0⦌)
        (C : SSet.Homotopy (SSet.const v) (𝟙 B))
        (hC : ∀ L : SSet.{0}, (SSet.const (X := L) v) ▷ Δ[1] ≫ C.h =
    …
  41. theorem OAI.Thomason.Construction.kan_finite_contracted_continuousFiberInclusion_weak line 849

    Source documentation

    The exact fibrewise Kan trivialization transports the preceding product theorem to any Kan fibration over the finite contracted base.

    theorem kan_finite_contracted_continuousFiberInclusion_weak
        {E B : SSet.{0}} [B.Finite] (v : B _⦋0⦌)
        (C : SSet.Homotopy (SSet.const v) (𝟙 B))
        (hC : ∀ L : SSet.{0}, (SSet.const (X := L) v) ▷ Δ[1] ≫ C.h =
    …
  42. theorem OAI.Thomason.Construction.kan_finite_contracted_simplicialFiberInclusion_weak line 870

    Source documentation

    At a vertex this is the inclusion of the original simplicial fibre, via the proved realization homeomorphism of literal point fibres.

    theorem kan_finite_contracted_simplicialFiberInclusion_weak
        {E B : SSet.{0}} [B.Finite] (v : B _⦋0⦌)
        (C : SSet.Homotopy (SSet.const v) (𝟙 B))
        (hC : ∀ L : SSet.{0}, (SSet.const (X := L) v) ▷ Δ[1] ≫ C.h =
    …
  43. theorem OAI.Thomason.Construction.kan_finite_contracted_baseChange_weak line 905

    Source documentation

    The pullback projection of a Kan fibration along a map between finite contracted parameter complexes is weak. The proof identifies a common literal vertex fibre; it does not assume right properness.

    theorem kan_finite_contracted_baseChange_weak
        {E B D : SSet.{0}} [B.Finite] [D.Finite]
        (v : B _⦋0⦌) (w : D _⦋0⦌)
        (C : SSet.Homotopy (SSet.const v) (𝟙 B))
        (T : SSet.Homotopy (SSet.const w) (𝟙 D))
        (hC : ∀ L : SSet.{0}, (SSet.const (X := L) v) ▷ Δ[1] ≫ C.h =
    …
  44. theorem OAI.Thomason.Construction.kan_finite_contracted_continuousFiberBaseChange_weak line 933

    Source documentation

    Under the same finite-parameter hypotheses, every real-point fibre map induced by base change is weak. This retains the exact specified point, rather than replacing it by a chosen vertex.

    theorem kan_finite_contracted_continuousFiberBaseChange_weak
        {E B D : SSet.{0}} [B.Finite] [D.Finite]
        (v : B _⦋0⦌) (w : D _⦋0⦌)
        (C : SSet.Homotopy (SSet.const v) (𝟙 B))
        (T : SSet.Homotopy (SSet.const w) (𝟙 D))
        (hC : ∀ L : SSet.{0}, (SSet.const (X := L) v) ▷ Δ[1] ≫ C.h =
    …
  45. theorem OAI.Thomason.Construction.realizedProductSimplexFiberInclusion_weak line 975

    Source documentation

    The literal fibre inclusion of a realized product projection over any point of the simplex is a weak equivalence.

    theorem realizedProductSimplexFiberInclusion_weak (F : SSet.{0}) (n : ℕ)
        (b : SSet.toTop.obj (Δ[n] : SSet.{0})) :
        topologicalWeakEquivalences (continuousFiberInclusion
          (SSet.toTop.map (snd F (Δ[n] : SSet.{0}))) b) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousFiberInclusion

  46. theorem OAI.Thomason.Construction.kan_simplex_continuousFiberInclusion_weak line 987

    Source documentation

    For a Kan fibration over a standard simplex, EVERY literal continuous fibre includes by a weak equivalence. The point need not be a vertex.

    theorem kan_simplex_continuousFiberInclusion_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ (Δ[n] : SSet.{0})) [HomotopicalAlgebra.Fibration p]
        (b : SSet.toTop.obj (Δ[n] : SSet.{0})) :
        topologicalWeakEquivalences (continuousFiberInclusion (SSet.toTop.map p) b) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousFiberInclusion

  47. theorem OAI.Thomason.Construction.kan_simplex_allPointFiberComparison_weak line 1004

    Source documentation

    The canonical constant-path comparison from the literal continuous fibre to the actual homotopy fibre is weak at every point of a simplex.

    theorem kan_simplex_allPointFiberComparison_weak {E : SSet.{0}} (n : ℕ)
        (p : E ⟶ (Δ[n] : SSet.{0})) [HomotopicalAlgebra.Fibration p]
        (b : SSet.toTop.obj (Δ[n] : SSet.{0})) :
        topologicalWeakEquivalences (continuousPointFiberComparison (SSet.toTop.map p) b) := by
    …

    Mentions: OAI.Thomason.Construction.topologicalWeakEquivalences, OAI.Thomason.Construction.continuousPointFiberComparison