455 lines
18 KiB
Text
455 lines
18 KiB
Text
/-
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Copyright (c) 2015 Ulrik Buchholtz, Egbert Rijke and Floris van Doorn. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Authors: Ulrik Buchholtz, Egbert Rijke, Floris van Doorn
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Formalization of the higher groups paper
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-/
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import .homotopy.EM
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open eq is_conn pointed is_trunc trunc equiv is_equiv trunc_index susp nat algebra
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prod.ops sigma sigma.ops category EM
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namespace higher_group
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set_option pp.binder_types true
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universe variable u
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/- Results not necessarily about higher groups which we repeat here, because they are mentioned in
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the higher group paper -/
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namespace hide
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open pushout
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definition connect_intro_pequiv {k : ℕ} {B : Type*} (A : Type*) (H : is_conn k B) :
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ppmap B (connect k A) ≃* ppmap B A :=
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is_conn.connect_intro_pequiv A H
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definition is_conn_fun_prod_of_wedge (n m : ℕ) (A B : Type*)
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[cA : is_conn n A] [cB : is_conn m B] : is_conn_fun (m + n) (@prod_of_wedge A B) :=
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is_conn_fun_prod_of_wedge n m A B
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definition is_trunc_ppi_of_is_conn (k n : ℕ) (X : Type*) (H : is_conn (k.-1) X)
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(Y : X → Type*) (H3 : Πx, is_trunc (k + n) (Y x)) :
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is_trunc n (Π*(x : X), Y x) :=
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is_conn.is_trunc_ppi_of_is_conn _ (k.-2) _ _ (le_of_eq (sub_one_add_plus_two_sub_one k n)⁻¹) _ H3
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end hide
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/- The k-groupal n-types.
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We require that the carrier has a point (preserved by the equivalence) -/
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structure GType (n k : ℕ) : Type := /- (n,k)GType, denoted here as [n;k]GType -/
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(car : ptrunctype.{u} n)
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(B : pconntype.{u} (k.-1)) /- this is Bᵏ -/
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(e : car ≃* Ω[k] B)
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structure InfGType (k : ℕ) : Type := /- (∞,k)GType, denoted here as [∞;k]GType -/
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(car : pType.{u})
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(B : pconntype.{u} (k.-1)) /- this is Bᵏ -/
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(e : car ≃* Ω[k] B)
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structure ωGType (n : ℕ) := /- (n,ω)GType, denoted here as [n;ω]GType -/
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(B : Π(k : ℕ), (n+k)-Type*[k.-1])
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(e : Π(k : ℕ), B k ≃* Ω (B (k+1)))
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attribute InfGType.car GType.car [coercion]
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variables {n k k' l : ℕ}
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notation `[`:95 n:0 `; ` k `]GType`:0 := GType n k
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notation `[∞; `:95 k:0 `]GType`:0 := InfGType k
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notation `[`:95 n:0 `;ω]GType`:0 := ωGType n
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open GType
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open InfGType (renaming B→iB e→ie)
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open ωGType (renaming B→oB e→oe)
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/- some basic properties -/
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lemma is_trunc_B' (G : [n;k]GType) : is_trunc (k+n) (B G) :=
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begin
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apply is_trunc_of_is_trunc_loopn,
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exact is_trunc_equiv_closed _ (e G) _,
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exact _
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end
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lemma is_trunc_B (G : [n;k]GType) : is_trunc (n+k) (B G) :=
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transport (λm, is_trunc m (B G)) (add.comm k n) (is_trunc_B' G)
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local attribute [instance] is_trunc_B
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definition GType.sigma_char (n k : ℕ) :
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GType.{u} n k ≃ Σ(B : pconntype.{u} (k.-1)), Σ(X : ptrunctype.{u} n), X ≃* Ω[k] B :=
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begin
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fapply equiv.MK,
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{ intro G, exact ⟨B G, G, e G⟩ },
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{ intro v, exact GType.mk v.2.1 v.1 v.2.2 },
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{ intro v, induction v with v₁ v₂, induction v₂, reflexivity },
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{ intro G, induction G, reflexivity },
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end
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definition GType_equiv (n k : ℕ) : [n;k]GType ≃ (n+k)-Type*[k.-1] :=
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GType.sigma_char n k ⬝e
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sigma_equiv_of_is_embedding_left_contr
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ptruncconntype.to_pconntype
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(is_embedding_ptruncconntype_to_pconntype (n+k) (k.-1))
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begin
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intro X,
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apply is_trunc_equiv_closed_rev -2,
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{ apply sigma_equiv_sigma_right, intro B',
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refine _ ⬝e (ptrunctype_eq_equiv B' (ptrunctype.mk (Ω[k] X) !is_trunc_loopn_nat pt))⁻¹ᵉ,
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assert lem : Π(A : n-Type*) (B : Type*) (H : is_trunc n B),
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(A ≃* B) ≃ (A ≃* (ptrunctype.mk B H pt)),
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{ intro A B'' H, induction B'', reflexivity },
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apply lem },
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exact _
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end
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begin
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intro B' H, apply fiber.mk (ptruncconntype.mk B' (is_trunc_B (GType.mk H.1 B' H.2)) pt _),
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induction B' with G' B' e', reflexivity
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end
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definition GType_equiv_pequiv {n k : ℕ} (G : [n;k]GType) : GType_equiv n k G ≃* B G :=
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by reflexivity
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definition GType_eq_equiv {n k : ℕ} (G H : [n;k]GType) : (G = H :> [n;k]GType) ≃ (B G ≃* B H) :=
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eq_equiv_fn_eq (GType_equiv n k) _ _ ⬝e !ptruncconntype_eq_equiv
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definition GType_eq {n k : ℕ} {G H : [n;k]GType} (e : B G ≃* B H) : G = H :=
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(GType_eq_equiv G H)⁻¹ᵉ e
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/- similar properties for [∞;k]GType -/
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definition InfGType.sigma_char (k : ℕ) :
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InfGType.{u} k ≃ Σ(B : pconntype.{u} (k.-1)), Σ(X : pType.{u}), X ≃* Ω[k] B :=
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begin
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fapply equiv.MK,
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{ intro G, exact ⟨iB G, G, ie G⟩ },
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{ intro v, exact InfGType.mk v.2.1 v.1 v.2.2 },
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{ intro v, induction v with v₁ v₂, induction v₂, reflexivity },
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{ intro G, induction G, reflexivity },
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end
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definition InfGType_equiv (k : ℕ) : [∞;k]GType ≃ Type*[k.-1] :=
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InfGType.sigma_char k ⬝e
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@sigma_equiv_of_is_contr_right _ _
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(λX, is_trunc_equiv_closed_rev -2 (sigma_equiv_sigma_right (λB', !pType_eq_equiv⁻¹ᵉ)) _)
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definition InfGType_equiv_pequiv {k : ℕ} (G : [∞;k]GType) : InfGType_equiv k G ≃* iB G :=
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by reflexivity
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definition InfGType_eq_equiv {k : ℕ} (G H : [∞;k]GType) : (G = H :> [∞;k]GType) ≃ (iB G ≃* iB H) :=
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eq_equiv_fn_eq (InfGType_equiv k) _ _ ⬝e !pconntype_eq_equiv
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definition InfGType_eq {k : ℕ} {G H : [∞;k]GType} (e : iB G ≃* iB H) : G = H :=
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(InfGType_eq_equiv G H)⁻¹ᵉ e
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/- alternative constructor for ωGType -/
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definition ωGType.mk_le {n : ℕ} (k₀ : ℕ)
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(C : Π⦃k : ℕ⦄, k₀ ≤ k → ((n+k)-Type*[k.-1] : Type.{u+1}))
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(e : Π⦃k : ℕ⦄ (H : k₀ ≤ k), C H ≃* Ω (C (le.step H))) : ([n;ω]GType : Type.{u+1}) :=
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begin
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fconstructor,
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{ apply rec_down_le _ k₀ C, intro n' D,
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refine (ptruncconntype.mk (Ω D) _ pt _),
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apply is_trunc_loop, apply is_trunc_ptruncconntype, apply is_conn_loop,
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apply is_conn_ptruncconntype },
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{ intro n', apply rec_down_le_univ, exact e, intro n D, reflexivity }
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end
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definition ωGType.mk_le_beta {n : ℕ} {k₀ : ℕ}
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(C : Π⦃k : ℕ⦄, k₀ ≤ k → ((n+k)-Type*[k.-1] : Type.{u+1}))
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(e : Π⦃k : ℕ⦄ (H : k₀ ≤ k), C H ≃* Ω (C (le.step H)))
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(k : ℕ) (H : k₀ ≤ k) : oB (ωGType.mk_le k₀ C e) k ≃* C H :=
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ptruncconntype_eq_equiv _ _ !rec_down_le_beta_ge
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definition GType_hom (G H : [n;k]GType) : Type :=
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B G →* B H
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definition ωGType_hom (G H : [n;ω]GType) : Type* :=
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pointed.MK
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(Σ(f : Πn, oB G n →* oB H n), Πn, psquare (f n) (Ω→ (f (n+1))) (oe G n) (oe H n))
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⟨λn, pconst (oB G n) (oB H n), λn, !phconst_square ⬝vp* !ap1_pconst⟩
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/- Constructions on higher groups -/
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definition Decat (G : [n+1;k]GType) : [n;k]GType :=
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GType.mk (ptrunctype.mk (ptrunc n G) _ pt) (pconntype.mk (ptrunc (n + k) (B G)) _ pt)
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abstract begin
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refine ptrunc_pequiv_ptrunc n (e G) ⬝e* _,
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symmetry, exact !loopn_ptrunc_pequiv_nat
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end end
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definition Disc (G : [n;k]GType) : [n+1;k]GType :=
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GType.mk (ptrunctype.mk G (show is_trunc (n.+1) G, from _) pt) (B G) (e G)
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definition Decat_adjoint_Disc (G : [n+1;k]GType) (H : [n;k]GType) :
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ppmap (B (Decat G)) (B H) ≃* ppmap (B G) (B (Disc H)) :=
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pmap_ptrunc_pequiv (n + k) (B G) (B H)
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definition Decat_adjoint_Disc_natural {G G' : [n+1;k]GType} {H H' : [n;k]GType}
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(g : B G' →* B G) (h : B H →* B H') :
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psquare (Decat_adjoint_Disc G H)
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(Decat_adjoint_Disc G' H')
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(ppcompose_left h ∘* ppcompose_right (ptrunc_functor _ g))
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(ppcompose_left h ∘* ppcompose_right g) :=
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pmap_ptrunc_pequiv_natural (n + k) g h
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definition Decat_Disc (G : [n;k]GType) : Decat (Disc G) = G :=
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GType_eq !ptrunc_pequiv
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definition InfDecat (n : ℕ) (G : [∞;k]GType) : [n;k]GType :=
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GType.mk (ptrunctype.mk (ptrunc n G) _ pt) (pconntype.mk (ptrunc (n + k) (iB G)) _ pt)
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abstract begin
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refine ptrunc_pequiv_ptrunc n (ie G) ⬝e* _,
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symmetry, exact !loopn_ptrunc_pequiv_nat
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end end
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definition InfDisc (n : ℕ) (G : [n;k]GType) : [∞;k]GType :=
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InfGType.mk G (B G) (e G)
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definition InfDecat_adjoint_InfDisc (G : [∞;k]GType) (H : [n;k]GType) :
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ppmap (B (InfDecat n G)) (B H) ≃* ppmap (iB G) (iB (InfDisc n H)) :=
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pmap_ptrunc_pequiv (n + k) (iB G) (B H)
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definition InfDecat_adjoint_InfDisc_natural {G G' : [∞;k]GType} {H H' : [n;k]GType}
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(g : iB G' →* iB G) (h : B H →* B H') :
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psquare (InfDecat_adjoint_InfDisc G H)
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(InfDecat_adjoint_InfDisc G' H')
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(ppcompose_left h ∘* ppcompose_right (ptrunc_functor _ g))
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(ppcompose_left h ∘* ppcompose_right g) :=
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pmap_ptrunc_pequiv_natural (n + k) g h
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definition InfDecat_InfDisc (G : [n;k]GType) : InfDecat n (InfDisc n G) = G :=
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GType_eq !ptrunc_pequiv
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definition Deloop (G : [n;k+1]GType) : [n+1;k]GType :=
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have is_conn k (B G), from is_conn_pconntype (B G),
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have is_trunc (n + (k + 1)) (B G), from is_trunc_B G,
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have is_trunc ((n + 1) + k) (B G), from transport (λ(n : ℕ), is_trunc n _) (succ_add n k)⁻¹ this,
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GType.mk (ptrunctype.mk (Ω[k] (B G)) !is_trunc_loopn_nat pt)
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(pconntype.mk (B G) !is_conn_of_is_conn_succ pt)
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(pequiv_of_equiv erfl idp)
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definition Loop (G : [n+1;k]GType) : [n;k+1]GType :=
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GType.mk (ptrunctype.mk (Ω G) !is_trunc_loop_nat pt)
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(connconnect k (B G))
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(loop_pequiv_loop (e G) ⬝e* (loopn_connect k (B G))⁻¹ᵉ*)
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definition Deloop_adjoint_Loop (G : [n;k+1]GType) (H : [n+1;k]GType) :
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ppmap (B (Deloop G)) (B H) ≃* ppmap (B G) (B (Loop H)) :=
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(connect_intro_pequiv _ !is_conn_pconntype)⁻¹ᵉ*
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definition Deloop_adjoint_Loop_natural {G G' : [n;k+1]GType} {H H' : [n+1;k]GType}
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(g : B G' →* B G) (h : B H →* B H') :
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psquare (Deloop_adjoint_Loop G H)
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(Deloop_adjoint_Loop G' H')
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(ppcompose_left h ∘* ppcompose_right g)
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(ppcompose_left (connect_functor k h) ∘* ppcompose_right g) :=
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(connect_intro_pequiv_natural g h _ _)⁻¹ʰ*
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definition Loop_Deloop (G : [n;k+1]GType) : Loop (Deloop G) = G :=
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GType_eq (connect_pequiv (is_conn_pconntype (B G)))
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definition Forget (G : [n;k+1]GType) : [n;k]GType :=
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have is_conn k (B G), from !is_conn_pconntype,
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GType.mk G (pconntype.mk (Ω (B G)) !is_conn_loop pt)
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abstract begin
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refine e G ⬝e* !loopn_succ_in
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end end
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definition Stabilize (G : [n;k]GType) : [n;k+1]GType :=
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have is_conn k (susp (B G)), from !is_conn_susp,
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have Hconn : is_conn k (ptrunc (n + k + 1) (susp (B G))), from !is_conn_ptrunc,
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GType.mk (ptrunctype.mk (ptrunc n (Ω[k+1] (susp (B G)))) _ pt)
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(pconntype.mk (ptrunc (n+k+1) (susp (B G))) Hconn pt)
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abstract begin
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refine !loopn_ptrunc_pequiv⁻¹ᵉ* ⬝e* _,
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apply loopn_pequiv_loopn,
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exact ptrunc_change_index !of_nat_add_of_nat _
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end end
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definition Stabilize_pequiv {G H : [n;k]GType} (e : B G ≃* B H) :
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B (Stabilize G) ≃* B (Stabilize H) :=
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ptrunc_pequiv_ptrunc (n+k+1) (susp_pequiv e)
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definition Stabilize_adjoint_Forget (G : [n;k]GType) (H : [n;k+1]GType) :
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ppmap (B (Stabilize G)) (B H) ≃* ppmap (B G) (B (Forget H)) :=
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have is_trunc (n + k + 1) (B H), from !is_trunc_B,
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pmap_ptrunc_pequiv (n + k + 1) (⅀ (B G)) (B H) ⬝e* susp_adjoint_loop (B G) (B H)
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definition Stabilize_adjoint_Forget_natural {G G' : [n;k]GType} {H H' : [n;k+1]GType}
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(g : B G' →* B G) (h : B H →* B H') :
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psquare (Stabilize_adjoint_Forget G H)
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(Stabilize_adjoint_Forget G' H')
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(ppcompose_left h ∘* ppcompose_right (ptrunc_functor (n+k+1) (⅀→ g)))
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(ppcompose_left (Ω→ h) ∘* ppcompose_right g) :=
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begin
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have is_trunc (n + k + 1) (B H), from !is_trunc_B,
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have is_trunc (n + k + 1) (B H'), from !is_trunc_B,
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refine pmap_ptrunc_pequiv_natural (n+k+1) (⅀→ g) h ⬝h* _,
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exact susp_adjoint_loop_natural_left g ⬝v* susp_adjoint_loop_natural_right h
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end
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definition Forget_Stabilize (H : k ≥ n + 2) (G : [n;k]GType) : B (Forget (Stabilize G)) ≃* B G :=
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loop_ptrunc_pequiv _ _ ⬝e*
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begin
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cases k with k,
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{ cases H },
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{ have k ≥ succ n, from le_of_succ_le_succ H,
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assert this : n + succ k ≤ 2 * k,
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{ rewrite [two_mul, add_succ, -succ_add], exact nat.add_le_add_right this k },
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exact freudenthal_pequiv this (B G) }
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end⁻¹ᵉ* ⬝e*
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ptrunc_pequiv (n + k) _
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definition Stabilize_Forget (H : k ≥ n + 1) (G : [n;k+1]GType) : B (Stabilize (Forget G)) ≃* B G :=
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begin
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assert lem1 : n + succ k ≤ 2 * k,
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{ rewrite [two_mul, add_succ, -succ_add], exact nat.add_le_add_right H k },
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have is_conn k (B G), from !is_conn_pconntype,
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have Π(G' : [n;k+1]GType), is_trunc (n + k + 1) (B G'), from is_trunc_B,
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note z := is_conn_fun_loop_susp_counit (B G) (nat.le_refl (2 * k)),
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refine ptrunc_pequiv_ptrunc_of_le (of_nat_le_of_nat lem1) (@(ptrunc_pequiv_ptrunc_of_is_conn_fun _ _) z) ⬝e*
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!ptrunc_pequiv,
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end
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definition stabilization (H : k ≥ n + 2) : is_equiv (@Stabilize n k) :=
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begin
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fapply adjointify,
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{ exact Forget },
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{ intro G, apply GType_eq, exact Stabilize_Forget (le.trans !self_le_succ H) _ },
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{ intro G, apply GType_eq, exact Forget_Stabilize H G }
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end
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/- an incomplete formalization of ω-Stabilization -/
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definition ωForget (k : ℕ) (G : [n;ω]GType) : [n;k]GType :=
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have is_trunc (n + k) (oB G k), from _,
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have is_trunc n (Ω[k] (oB G k)), from !is_trunc_loopn_nat,
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GType.mk (ptrunctype.mk (Ω[k] (oB G k)) _ pt) (oB G k) (pequiv_of_equiv erfl idp)
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definition nStabilize (H : k ≤ l) (G : GType.{u} n k) : GType.{u} n l :=
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begin
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induction H with l H IH, exact G, exact Stabilize IH
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end
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definition nStabilize_pequiv (H H' : k ≤ l) {G G' : [n;k]GType}
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(e : B G ≃* B G') : B (nStabilize H G) ≃* B (nStabilize H' G') :=
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begin
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induction H with l H IH,
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{ exact e ⬝e* pequiv_ap (λH, B (nStabilize H G')) (is_prop.elim (le.refl k) H') },
|
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cases H' with l H'',
|
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{ exfalso, exact not_succ_le_self H },
|
||
exact Stabilize_pequiv (IH H'')
|
||
end
|
||
|
||
definition nStabilize_pequiv_of_eq (H : k ≤ l) (p : k = l) (G : [n;k]GType) :
|
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B (nStabilize H G) ≃* B G :=
|
||
begin induction p, exact pequiv_ap (λH, B (nStabilize H G)) (is_prop.elim H (le.refl k)) end
|
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|
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definition ωStabilize_of_le (H : k ≥ n + 2) (G : [n;k]GType) : [n;ω]GType :=
|
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ωGType.mk_le k (λl H', GType_equiv n l (nStabilize H' G))
|
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(λl H', (Forget_Stabilize (le.trans H H') (nStabilize H' G))⁻¹ᵉ*)
|
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|
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definition ωStabilize_of_le_beta (H : k ≥ n + 2) (G : [n;k]GType) (H' : l ≥ k) :
|
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oB (ωStabilize_of_le H G) l ≃* GType_equiv n l (nStabilize H' G) :=
|
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ptruncconntype_eq_equiv _ _ !rec_down_le_beta_ge
|
||
|
||
definition ωStabilize_of_le_pequiv (H : k ≥ n + 2) (H' : k' ≥ n + 2) {G : [n;k]GType}
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{G' : [n;k']GType} (e : B G ≃* B G') (l : ℕ) (Hl : l ≥ k) (Hl' : l ≥ k') (p : k = k') :
|
||
oB (ωStabilize_of_le H G) l ≃* oB (ωStabilize_of_le H' G') l :=
|
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begin
|
||
refine ωStabilize_of_le_beta H G Hl ⬝e* _ ⬝e* (ωStabilize_of_le_beta H' G' Hl')⁻¹ᵉ*,
|
||
induction p,
|
||
exact nStabilize_pequiv _ _ e
|
||
end
|
||
|
||
definition ωForget_ωStabilize_of_le (H : k ≥ n + 2) (G : [n;k]GType) :
|
||
B (ωForget k (ωStabilize_of_le H G)) ≃* B G :=
|
||
ωStabilize_of_le_beta H _ (le.refl k)
|
||
|
||
definition ωStabilize (G : [n;k]GType) : [n;ω]GType :=
|
||
ωStabilize_of_le !le_max_left (nStabilize !le_max_right G)
|
||
|
||
definition ωForget_ωStabilize (H : k ≥ n + 2) (G : [n;k]GType) :
|
||
B (ωForget k (ωStabilize G)) ≃* B G :=
|
||
begin
|
||
refine _ ⬝e* ωForget_ωStabilize_of_le H G,
|
||
esimp [ωForget, ωStabilize],
|
||
have H' : max (n + 2) k = k, from max_eq_right H,
|
||
exact ωStabilize_of_le_pequiv !le_max_left H (nStabilize_pequiv_of_eq _ H'⁻¹ _)
|
||
k (le_of_eq H') (le.refl k) H'
|
||
end
|
||
|
||
/-
|
||
definition ωStabilize_adjoint_ωForget (G : [n;k]GType) (H : [n;ω]GType) :
|
||
ωGType_hom (ωStabilize G) H ≃* ppmap (B G) (B (ωForget k H)) :=
|
||
sorry
|
||
|
||
definition ωStabilize_ωForget (G : [n;ω]GType) (l : ℕ) :
|
||
oB (ωStabilize (ωForget k G)) l ≃* oB G l :=
|
||
begin
|
||
exact sorry
|
||
end
|
||
|
||
definition ωstabilization (H : k ≥ n + 2) : is_equiv (@ωStabilize n k) :=
|
||
begin
|
||
apply adjointify _ (ωForget k),
|
||
{ intro G', exact sorry },
|
||
{ intro G, apply GType_eq, exact ωForget_ωStabilize H G }
|
||
end
|
||
-/
|
||
|
||
definition is_trunc_GType_hom (G H : [n;k]GType) : is_trunc n (GType_hom G H) :=
|
||
is_trunc_pmap_of_is_conn _ (k.-2) _ (k + n) _ (le_of_eq (sub_one_add_plus_two_sub_one k n)⁻¹)
|
||
(is_trunc_B' H)
|
||
|
||
definition is_set_GType_hom (G H : [0;k]GType) : is_set (GType_hom G H) :=
|
||
is_trunc_GType_hom G H
|
||
|
||
definition is_trunc_GType (n k : ℕ) : is_trunc (n + 1) [n;k]GType :=
|
||
begin
|
||
apply @is_trunc_equiv_closed_rev _ _ (n + 1) (GType_equiv n k),
|
||
apply is_trunc_succ_intro, intros X Y,
|
||
apply @is_trunc_equiv_closed_rev _ _ _ (ptruncconntype_eq_equiv X Y),
|
||
apply @is_trunc_equiv_closed_rev _ _ _ (pequiv.sigma_char_pmap X Y),
|
||
apply @is_trunc_subtype (X →* Y) (λ f, trunctype.mk' -1 (is_equiv f)),
|
||
exact is_trunc_GType_hom ((GType_equiv n k)⁻¹ᵉ X) ((GType_equiv n k)⁻¹ᵉ Y)
|
||
end
|
||
|
||
local attribute [instance] is_set_GType_hom
|
||
|
||
definition cGType [constructor] (k : ℕ) : Precategory :=
|
||
pb_Precategory (cptruncconntype' (k.-1))
|
||
(GType_equiv 0 k ⬝e ptruncconntype_equiv (ap of_nat (zero_add k)) idp ⬝e
|
||
(ptruncconntype'_equiv_ptruncconntype (k.-1))⁻¹ᵉ)
|
||
|
||
example (k : ℕ) : Precategory.carrier (cGType k) = [0;k]GType := by reflexivity
|
||
example (k : ℕ) (G H : cGType k) : (G ⟶ H) = (B G →* B H) := by reflexivity
|
||
|
||
definition cGType_equivalence_cType [constructor] (k : ℕ) : cGType k ≃c cType*[k.-1] :=
|
||
!pb_Precategory_equivalence_of_equiv
|
||
|
||
definition cGType_equivalence_Grp [constructor] : cGType.{u} 1 ≃c Grp.{u} :=
|
||
equivalence.trans !pb_Precategory_equivalence_of_equiv
|
||
(equivalence.trans (equivalence.symm Grp_equivalence_cptruncconntype')
|
||
proof equivalence.refl _ qed)
|
||
|
||
definition cGType_equivalence_AbGrp [constructor] (k : ℕ) : cGType.{u} (k+2) ≃c AbGrp.{u} :=
|
||
equivalence.trans !pb_Precategory_equivalence_of_equiv
|
||
(equivalence.trans (equivalence.symm (AbGrp_equivalence_cptruncconntype' k))
|
||
proof equivalence.refl _ qed)
|
||
|
||
/-
|
||
print axioms GType_equiv
|
||
print axioms InfGType_equiv
|
||
print axioms Decat_adjoint_Disc
|
||
print axioms Decat_adjoint_Disc_natural
|
||
print axioms InfDecat_adjoint_InfDisc
|
||
print axioms InfDecat_adjoint_InfDisc_natural
|
||
print axioms Deloop_adjoint_Loop
|
||
print axioms Deloop_adjoint_Loop_natural
|
||
print axioms Stabilize_adjoint_Forget
|
||
print axioms Stabilize_adjoint_Forget_natural
|
||
print axioms stabilization
|
||
print axioms is_trunc_GType
|
||
print axioms cGType_equivalence_Grp
|
||
print axioms cGType_equivalence_AbGrp
|
||
-/
|
||
|
||
end higher_group
|