+++ /dev/null
-(*********************************************************************************************************************************)
-(* ReificationsEquivalentToGeneralizedArrows: *)
-(* *)
-(* The category of generalized arrows and the category of reifications are equivalent categories. *)
-(* *)
-(*********************************************************************************************************************************)
-
-Generalizable All Variables.
-Require Import Preamble.
-Require Import General.
-Require Import Categories_ch1_3.
-Require Import Functors_ch1_4.
-Require Import Isomorphisms_ch1_5.
-Require Import ProductCategories_ch1_6_1.
-Require Import OppositeCategories_ch1_6_2.
-Require Import Enrichment_ch2_8.
-Require Import Subcategories_ch7_1.
-Require Import NaturalTransformations_ch7_4.
-Require Import NaturalIsomorphisms_ch7_5.
-Require Import MonoidalCategories_ch7_8.
-Require Import Coherence_ch7_8.
-Require Import Enrichment_ch2_8.
-Require Import RepresentableStructure_ch7_2.
-Require Import Reification.
-Require Import GeneralizedArrow.
-Require Import GeneralizedArrowFromReification.
-Require Import ReificationFromGeneralizedArrow.
-Require Import ReificationCategory.
-Require Import GeneralizedArrowCategory.
-
-Section ReificationsEquivalentToGeneralizedArrows.
-
- Ltac if_transitive :=
- match goal with [ |- ?A ≃ ?B ] => refine (@if_comp _ _ _ _ _ _ _ A _ _ _ B _ _)
- end.
-
- Lemma roundtrip_lemma'
- `{C:Category}`{D:Category}`{E:Category}
- {Gobj}(G:Functor E D Gobj) G_full G_faithful {Fobj}(F:Functor C (FullImage G) Fobj) :
- ((F >>>> ff_functor_section_functor G G_full G_faithful) >>>> G) ≃ (F >>>> InclusionFunctor _ _).
- if_transitive.
- apply (if_associativity F (ff_functor_section_functor G _ _) G).
- apply if_respects.
- apply if_id.
- if_transitive; [ idtac | apply if_left_identity ].
- apply (if_comp(F2:=(ff_functor_section_functor G G_full G_faithful) >>>> RestrictToImage G >>>> InclusionFunctor _ _)).
- apply if_inv.
- apply (if_associativity (ff_functor_section_functor G G_full G_faithful) (RestrictToImage G) (InclusionFunctor D (FullImage G))).
- apply if_respects.
- apply ff_functor_section_splits_niso.
- apply if_id.
- Qed.
-
- Definition roundtrip_lemma
- `(K:SurjectiveEnrichment se) `(C:MonicMonoidalEnrichment e ce) (reification : Reification K C (me_i C))
- := roundtrip_lemma' (RepresentableFunctor C (me_i C)) (ffme_mf_full C) (ffme_mf_faithful C) (step1_functor K C reification).
-
- Lemma roundtrip_reification_to_reification
- `(K:SurjectiveEnrichment se) `(C:MonicMonoidalEnrichment e ce) (reification : Reification K C (me_i C))
- : reification ≃ reification_from_garrow K C (garrow_from_reification K C reification).
- simpl.
- unfold mon_f.
- unfold garrow_functor.
- apply (if_comp(F2:=(step1_functor K C reification >>>> InclusionFunctor _ (FullImage (RepresentableFunctor C (me_i C)))))).
- apply (@step1_niso _ K _ _ C reification).
- apply (if_inv (roundtrip_lemma K C reification)).
- Qed.
-
- Lemma roundtrip_garrow_to_garrow
- `(K:SurjectiveEnrichment se) `(C:MonicMonoidalEnrichment e ce) (garrow : GeneralizedArrow K C)
- : garrow ≃ garrow_from_reification K C (reification_from_garrow K C garrow).
- apply (ffc_functor_weakly_monic _ (ffme_mf_conservative C)).
- apply if_inv.
- apply (if_comp(F2:=(step1_functor K C (reification_from_garrow K C garrow)
- >>>> InclusionFunctor _ (FullImage (RepresentableFunctor C (me_i C)))))).
- unfold mf_f.
- unfold garrow_from_reification.
- unfold garrow_functor.
- unfold step2_functor.
- set (@roundtrip_lemma _ K _ _ C) as q.
- apply (q (reification_from_garrow K C garrow)).
- apply if_inv.
- apply (step1_niso K C (reification_from_garrow K C garrow)).
- Qed.
-
-End ReificationsEquivalentToGeneralizedArrows.