lean2/hott/hit/two_quotient.hlean
2015-11-22 18:29:37 -08:00

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Text

/-
Copyright (c) 2015 Floris van Doorn. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Floris van Doorn
-/
import homotopy.circle eq2 algebra.e_closure cubical.squareover cubical.cube cubical.square2
open quotient eq circle sum sigma equiv function relation e_closure
/-
This files defines a general class of nonrecursive HITs using just quotients.
We can define any HIT X which has
- a single 0-constructor
f : A → X (for some type A)
- a single 1-constructor
e : Π{a a' : A}, R a a' → a = a' (for some (type-valued) relation R on A)
and furthermore has 2-constructors which are all of the form
p = p'
where p, p' are of the form
- refl (f a), for some a : A;
- e r, for some r : R a a';
- ap f q, where q : a = a' :> A;
- inverses of such paths;
- concatenations of such paths.
so an example 2-constructor could be (as long as it typechecks):
ap f q' ⬝ ((e r)⁻¹ ⬝ ap f q)⁻¹ ⬝ e r' = idp
-/
namespace simple_two_quotient
section
parameters {A : Type}
(R : A → A → Type)
local abbreviation T := e_closure R -- the (type-valued) equivalence closure of R
parameter (Q : Π⦃a⦄, T a a → Type)
variables ⦃a a' : A⦄ {s : R a a'} {r : T a a}
local abbreviation B := A ⊎ Σ(a : A) (r : T a a), Q r
inductive pre_two_quotient_rel : B → B → Type :=
| pre_Rmk {} : Π⦃a a'⦄ (r : R a a'), pre_two_quotient_rel (inl a) (inl a')
--BUG: if {} not provided, the alias for pre_Rmk is wrong
definition pre_two_quotient := quotient pre_two_quotient_rel
open pre_two_quotient_rel
local abbreviation C := quotient pre_two_quotient_rel
protected definition j [constructor] (a : A) : C := class_of pre_two_quotient_rel (inl a)
protected definition pre_aux [constructor] (q : Q r) : C :=
class_of pre_two_quotient_rel (inr ⟨a, r, q⟩)
protected definition e (s : R a a') : j a = j a' := eq_of_rel _ (pre_Rmk s)
protected definition et (t : T a a') : j a = j a' := e_closure.elim e t
protected definition f [unfold 7] (q : Q r) : S¹ → C :=
circle.elim (j a) (et r)
protected definition pre_rec [unfold 8] {P : C → Type}
(Pj : Πa, P (j a)) (Pa : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), P (pre_aux q))
(Pe : Π⦃a a' : A⦄ (s : R a a'), Pj a =[e s] Pj a') (x : C) : P x :=
begin
induction x with p,
{ induction p,
{ apply Pj},
{ induction a with a1 a2, induction a2, apply Pa}},
{ induction H, esimp, apply Pe},
end
protected definition pre_elim [unfold 8] {P : Type} (Pj : A → P)
(Pa : Π⦃a : A⦄ ⦃r : T a a⦄, Q r → P) (Pe : Π⦃a a' : A⦄ (s : R a a'), Pj a = Pj a') (x : C)
: P :=
pre_rec Pj Pa (λa a' s, pathover_of_eq (Pe s)) x
protected theorem rec_e {P : C → Type}
(Pj : Πa, P (j a)) (Pa : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), P (pre_aux q))
(Pe : Π⦃a a' : A⦄ (s : R a a'), Pj a =[e s] Pj a') ⦃a a' : A⦄ (s : R a a')
: apdo (pre_rec Pj Pa Pe) (e s) = Pe s :=
!rec_eq_of_rel
protected theorem elim_e {P : Type} (Pj : A → P) (Pa : Π⦃a : A⦄ ⦃r : T a a⦄, Q r → P)
(Pe : Π⦃a a' : A⦄ (s : R a a'), Pj a = Pj a') ⦃a a' : A⦄ (s : R a a')
: ap (pre_elim Pj Pa Pe) (e s) = Pe s :=
begin
apply eq_of_fn_eq_fn_inv !(pathover_constant (e s)),
rewrite [▸*,-apdo_eq_pathover_of_eq_ap,↑pre_elim,rec_e],
end
protected definition elim_et {P : Type} (Pj : A → P) (Pa : Π⦃a : A⦄ ⦃r : T a a⦄, Q r → P)
(Pe : Π⦃a a' : A⦄ (s : R a a'), Pj a = Pj a') ⦃a a' : A⦄ (t : T a a')
: ap (pre_elim Pj Pa Pe) (et t) = e_closure.elim Pe t :=
ap_e_closure_elim_h e (elim_e Pj Pa Pe) t
protected definition rec_et {P : C → Type}
(Pj : Πa, P (j a)) (Pa : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), P (pre_aux q))
(Pe : Π⦃a a' : A⦄ (s : R a a'), Pj a =[e s] Pj a') ⦃a a' : A⦄ (t : T a a')
: apdo (pre_rec Pj Pa Pe) (et t) = e_closure.elimo e Pe t :=
ap_e_closure_elimo_h e Pe (rec_e Pj Pa Pe) t
inductive simple_two_quotient_rel : C → C → Type :=
| Rmk {} : Π{a : A} {r : T a a} (q : Q r) (x : circle),
simple_two_quotient_rel (f q x) (pre_aux q)
open simple_two_quotient_rel
definition simple_two_quotient := quotient simple_two_quotient_rel
local abbreviation D := simple_two_quotient
local abbreviation i := class_of simple_two_quotient_rel
definition incl0 (a : A) : D := i (j a)
protected definition aux (q : Q r) : D := i (pre_aux q)
definition incl1 (s : R a a') : incl0 a = incl0 a' := ap i (e s)
definition inclt (t : T a a') : incl0 a = incl0 a' := e_closure.elim incl1 t
-- "wrong" version inclt, which is ap i (p ⬝ q) instead of ap i p ⬝ ap i q
-- it is used in the proof, because incltw is easier to work with
protected definition incltw (t : T a a') : incl0 a = incl0 a' := ap i (et t)
protected definition inclt_eq_incltw (t : T a a') : inclt t = incltw t :=
(ap_e_closure_elim i e t)⁻¹
definition incl2' (q : Q r) (x : S¹) : i (f q x) = aux q :=
eq_of_rel simple_two_quotient_rel (Rmk q x)
protected definition incl2w (q : Q r) : incltw r = idp :=
(ap02 i (elim_loop (j a) (et r))⁻¹) ⬝
(ap_compose i (f q) loop)⁻¹ ⬝
ap_is_constant (incl2' q) loop ⬝
!con.right_inv
definition incl2 (q : Q r) : inclt r = idp :=
inclt_eq_incltw r ⬝ incl2w q
local attribute simple_two_quotient f i D incl0 aux incl1 incl2' inclt [reducible]
local attribute i aux incl0 [constructor]
parameters {R Q}
protected definition rec {P : D → Type} (P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r),
change_path (incl2 q) (e_closure.elimo incl1 P1 r) = idpo) (x : D) : P x :=
begin
induction x,
{ refine (pre_rec _ _ _ a),
{ exact P0},
{ intro a r q, exact incl2' q base ▸ P0 a},
{ intro a a' s, exact pathover_of_pathover_ap P i (P1 s)}},
{ exact abstract [irreducible] begin induction H, induction x,
{ esimp, exact pathover_tr (incl2' q base) (P0 a)},
{ apply pathover_pathover,
esimp, fold [i, incl2' q],
refine eq_hconcato _ _, apply _,
{ transitivity _,
{ apply ap (pathover_ap _ _),
transitivity _, apply apdo_compose2 (pre_rec P0 _ _) (f q) loop,
apply ap (pathover_of_pathover_ap _ _),
transitivity _, apply apdo_change_path, exact !elim_loop⁻¹,
transitivity _,
apply ap (change_path _),
transitivity _, apply rec_et,
transitivity (pathover_of_pathover_ap P i (change_path (inclt_eq_incltw r)
(e_closure.elimo incl1 (λ (a a' : A) (s : R a a'), P1 s) r))),
apply e_closure_elimo_ap,
exact idp,
apply change_path_pathover_of_pathover_ap},
esimp, transitivity _, apply pathover_ap_pathover_of_pathover_ap P i (f q),
transitivity _, apply ap (change_path _), apply to_right_inv !pathover_compose,
do 2 (transitivity _; exact !change_path_con⁻¹),
transitivity _, apply ap (change_path _),
exact (to_left_inv (change_path_equiv _ _ (incl2 q)) _)⁻¹, esimp,
rewrite P2, transitivity _; exact !change_path_con⁻¹, apply ap (λx, change_path x _),
rewrite [↑incl2, con_inv], transitivity _, exact !con.assoc⁻¹,
rewrite [inv_con_cancel_right, ↑incl2w, ↑ap02, +con_inv, +ap_inv, +inv_inv, -+con.assoc,
+con_inv_cancel_right], reflexivity},
rewrite [change_path_con, apdo_constant],
apply squareover_change_path_left, apply squareover_change_path_right',
apply squareover_change_path_left,
refine change_square _ vrflo,
symmetry, apply inv_ph_eq_of_eq_ph, rewrite [ap_is_constant_natural_square],
apply whisker_bl_whisker_tl_eq} end end},
end
protected definition rec_on [reducible] {P : D → Type} (x : D) (P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r),
change_path (incl2 q) (e_closure.elimo incl1 P1 r) = idpo) : P x :=
rec P0 P1 P2 x
theorem rec_incl1 {P : D → Type} (P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r),
change_path (incl2 q) (e_closure.elimo incl1 P1 r) = idpo) ⦃a a' : A⦄ (s : R a a')
: apdo (rec P0 P1 P2) (incl1 s) = P1 s :=
begin
unfold [rec, incl1], refine !apdo_ap ⬝ _, esimp, rewrite rec_e,
apply to_right_inv !pathover_compose
end
theorem rec_inclt {P : D → Type} (P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r),
change_path (incl2 q) (e_closure.elimo incl1 P1 r) = idpo) ⦃a a' : A⦄ (t : T a a')
: apdo (rec P0 P1 P2) (inclt t) = e_closure.elimo incl1 P1 t :=
ap_e_closure_elimo_h incl1 P1 (rec_incl1 P0 P1 P2) t
protected definition elim {P : Type} (P0 : A → P)
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
(x : D) : P :=
begin
induction x,
{ refine (pre_elim _ _ _ a),
{ exact P0},
{ intro a r q, exact P0 a},
{ exact P1}},
{ exact abstract begin induction H, induction x,
{ exact idpath (P0 a)},
{ unfold f, apply eq_pathover, apply hdeg_square,
exact abstract ap_compose (pre_elim P0 _ P1) (f q) loop ⬝
ap _ !elim_loop ⬝
!elim_et ⬝
P2 q ⬝
!ap_constant⁻¹ end} end end},
end
local attribute elim [unfold 8]
protected definition elim_on {P : Type} (x : D) (P0 : A → P)
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
: P :=
elim P0 P1 P2 x
definition elim_incl1 {P : Type} {P0 : A → P}
{P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a'}
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
⦃a a' : A⦄ (s : R a a') : ap (elim P0 P1 P2) (incl1 s) = P1 s :=
(ap_compose (elim P0 P1 P2) i (e s))⁻¹ ⬝ !elim_e
definition elim_inclt {P : Type} {P0 : A → P}
{P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a'}
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
⦃a a' : A⦄ (t : T a a') : ap (elim P0 P1 P2) (inclt t) = e_closure.elim P1 t :=
ap_e_closure_elim_h incl1 (elim_incl1 P2) t
protected definition elim_incltw {P : Type} {P0 : A → P}
{P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a'}
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
⦃a a' : A⦄ (t : T a a') : ap (elim P0 P1 P2) (incltw t) = e_closure.elim P1 t :=
(ap_compose (elim P0 P1 P2) i (et t))⁻¹ ⬝ !elim_et
protected theorem elim_inclt_eq_elim_incltw {P : Type} {P0 : A → P}
{P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a'}
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
⦃a a' : A⦄ (t : T a a')
: elim_inclt P2 t = ap (ap (elim P0 P1 P2)) (inclt_eq_incltw t) ⬝ elim_incltw P2 t :=
begin
unfold [elim_inclt,elim_incltw,inclt_eq_incltw,et],
refine !ap_e_closure_elim_h_eq ⬝ _,
rewrite [ap_inv,-con.assoc],
xrewrite [eq_of_square (ap_ap_e_closure_elim i (elim P0 P1 P2) e t)⁻¹ʰ],
rewrite [↓incl1,con.assoc], apply whisker_left,
rewrite [↑[elim_et,elim_incl1],+ap_e_closure_elim_h_eq,con_inv,↑[i,function.compose]],
rewrite [-con.assoc (_ ⬝ _),con.assoc _⁻¹,con.left_inv,▸*,-ap_inv,-ap_con],
apply ap (ap _),
krewrite [-eq_of_homotopy3_inv,-eq_of_homotopy3_con]
end
definition elim_incl2' {P : Type} {P0 : A → P}
{P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a'}
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
⦃a : A⦄ ⦃r : T a a⦄ (q : Q r) : ap (elim P0 P1 P2) (incl2' q base) = idpath (P0 a) :=
!elim_eq_of_rel
protected theorem elim_incl2w {P : Type} (P0 : A → P)
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
⦃a : A⦄ ⦃r : T a a⦄ (q : Q r)
: square (ap02 (elim P0 P1 P2) (incl2w q)) (P2 q) (elim_incltw P2 r) idp :=
begin
esimp [incl2w,ap02],
rewrite [+ap_con (ap _),▸*],
xrewrite [-ap_compose (ap _) (ap i)],
rewrite [+ap_inv],
xrewrite [eq_top_of_square
((ap_compose_natural (elim P0 P1 P2) i (elim_loop (j a) (et r)))⁻¹ʰ⁻¹ᵛ ⬝h
(ap_ap_compose (elim P0 P1 P2) i (f q) loop)⁻¹ʰ⁻¹ᵛ ⬝h
ap_ap_is_constant (elim P0 P1 P2) (incl2' q) loop ⬝h
ap_con_right_inv_sq (elim P0 P1 P2) (incl2' q base)),
↑[elim_incltw]],
apply whisker_tl,
rewrite [ap_is_constant_eq],
xrewrite [naturality_apdo_eq (λx, !elim_eq_of_rel) loop],
rewrite [↑elim_2,rec_loop,square_of_pathover_concato_eq,square_of_pathover_eq_concato,
eq_of_square_vconcat_eq,eq_of_square_eq_vconcat],
apply eq_vconcat,
{ apply ap (λx, _ ⬝ eq_con_inv_of_con_eq ((_ ⬝ x ⬝ _)⁻¹ ⬝ _) ⬝ _),
transitivity _, apply ap eq_of_square,
apply to_right_inv !eq_pathover_equiv_square (hdeg_square (elim_1 P A R Q P0 P1 a r q P2)),
transitivity _, apply eq_of_square_hdeg_square,
unfold elim_1, reflexivity},
rewrite [+con_inv,whisker_left_inv,+inv_inv,-whisker_right_inv,
con.assoc (whisker_left _ _),con.assoc _ (whisker_right _ _),▸*,
whisker_right_con_whisker_left _ !ap_constant],
xrewrite [-con.assoc _ _ (whisker_right _ _)],
rewrite [con.assoc _ _ (whisker_left _ _),idp_con_whisker_left,▸*,
con.assoc _ !ap_constant⁻¹,con.left_inv],
xrewrite [eq_con_inv_of_con_eq_whisker_left,▸*],
rewrite [+con.assoc _ _ !con.right_inv,
right_inv_eq_idp (
(λ(x : ap (elim P0 P1 P2) (incl2' q base) = idpath
(elim P0 P1 P2 (class_of simple_two_quotient_rel (f q base)))), x)
(elim_incl2' P2 q)),
↑[whisker_left]],
xrewrite [con2_con_con2],
rewrite [idp_con,↑elim_incl2',con.left_inv,whisker_right_inv,↑whisker_right],
xrewrite [con.assoc _ _ (_ ◾ _)],
rewrite [con.left_inv,▸*,-+con.assoc,con.assoc _⁻¹,↑[elim,function.compose],con.left_inv,
▸*,↑j,con.left_inv,idp_con],
apply square_of_eq, reflexivity
end
theorem elim_incl2 {P : Type} (P0 : A → P)
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a')
(P2 : Π⦃a : A⦄ ⦃r : T a a⦄ (q : Q r), e_closure.elim P1 r = idp)
⦃a : A⦄ ⦃r : T a a⦄ (q : Q r)
: square (ap02 (elim P0 P1 P2) (incl2 q)) (P2 q) (elim_inclt P2 r) idp :=
begin
rewrite [↑incl2,↑ap02,ap_con,elim_inclt_eq_elim_incltw],
apply whisker_tl,
apply elim_incl2w
end
end
end simple_two_quotient
attribute simple_two_quotient.j [constructor]
attribute simple_two_quotient.rec simple_two_quotient.elim [unfold 8] [recursor 8]
--attribute simple_two_quotient.elim_type [unfold 9] -- TODO
attribute simple_two_quotient.rec_on simple_two_quotient.elim_on [unfold 5]
--attribute simple_two_quotient.elim_type_on [unfold 6] -- TODO
namespace two_quotient
open simple_two_quotient
section
parameters {A : Type}
(R : A → A → Type)
local abbreviation T := e_closure R -- the (type-valued) equivalence closure of R
parameter (Q : Π⦃a a'⦄, T a a' → T a a' → Type)
variables ⦃a a' : A⦄ {s : R a a'} {t t' : T a a'}
inductive two_quotient_Q : Π⦃a : A⦄, e_closure R a a → Type :=
| Qmk : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄, Q t t' → two_quotient_Q (t ⬝r t'⁻¹ʳ)
open two_quotient_Q
local abbreviation Q2 := two_quotient_Q
definition two_quotient := simple_two_quotient R Q2
definition incl0 (a : A) : two_quotient := incl0 _ _ a
definition incl1 (s : R a a') : incl0 a = incl0 a' := incl1 _ _ s
definition inclt (t : T a a') : incl0 a = incl0 a' := e_closure.elim incl1 t
definition incl2 (q : Q t t') : inclt t = inclt t' :=
eq_of_con_inv_eq_idp (incl2 _ _ (Qmk R q))
parameters {R Q}
protected definition rec {P : two_quotient → Type} (P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'),
change_path (incl2 q) (e_closure.elimo incl1 P1 t) = e_closure.elimo incl1 P1 t')
(x : two_quotient) : P x :=
begin
induction x,
{ exact P0 a},
{ exact P1 s},
{ induction q with a a' t t' q,
rewrite [elimo_con (simple_two_quotient.incl1 R Q2) P1,
elimo_inv (simple_two_quotient.incl1 R Q2) P1,
-whisker_right_eq_of_con_inv_eq_idp (simple_two_quotient.incl2 R Q2 (Qmk R q)),
change_path_con],
xrewrite [change_path_cono],
refine ap (λx, change_path _ (_ ⬝o x)) !change_path_invo ⬝ _, esimp,
apply cono_invo_eq_idpo, apply P2}
end
protected definition rec_on [reducible] {P : two_quotient → Type} (x : two_quotient)
(P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'),
change_path (incl2 q) (e_closure.elimo incl1 P1 t) = e_closure.elimo incl1 P1 t') : P x :=
rec P0 P1 P2 x
theorem rec_incl1 {P : two_quotient → Type} (P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'),
change_path (incl2 q) (e_closure.elimo incl1 P1 t) = e_closure.elimo incl1 P1 t')
⦃a a' : A⦄ (s : R a a') : apdo (rec P0 P1 P2) (incl1 s) = P1 s :=
rec_incl1 _ _ _ s
theorem rec_inclt {P : two_quotient → Type} (P0 : Π(a : A), P (incl0 a))
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a =[incl1 s] P0 a')
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'),
change_path (incl2 q) (e_closure.elimo incl1 P1 t) = e_closure.elimo incl1 P1 t')
⦃a a' : A⦄ (t : T a a') : apdo (rec P0 P1 P2) (inclt t) = e_closure.elimo incl1 P1 t :=
rec_inclt _ _ _ t
protected definition elim {P : Type} (P0 : A → P)
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a')
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'), e_closure.elim P1 t = e_closure.elim P1 t')
(x : two_quotient) : P :=
begin
induction x,
{ exact P0 a},
{ exact P1 s},
{ exact abstract [unfold 10] begin induction q with a a' t t' q,
esimp [e_closure.elim],
apply con_inv_eq_idp, exact P2 q end end},
end
local attribute elim [unfold 8]
protected definition elim_on {P : Type} (x : two_quotient) (P0 : A → P)
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a')
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'), e_closure.elim P1 t = e_closure.elim P1 t')
: P :=
elim P0 P1 P2 x
definition elim_incl1 {P : Type} {P0 : A → P}
{P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a'}
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'), e_closure.elim P1 t = e_closure.elim P1 t')
⦃a a' : A⦄ (s : R a a') : ap (elim P0 P1 P2) (incl1 s) = P1 s :=
!elim_incl1
definition elim_inclt {P : Type} {P0 : A → P}
{P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a'}
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'), e_closure.elim P1 t = e_closure.elim P1 t')
⦃a a' : A⦄ (t : T a a') : ap (elim P0 P1 P2) (inclt t) = e_closure.elim P1 t :=
!elim_inclt
theorem elim_incl2 {P : Type} (P0 : A → P)
(P1 : Π⦃a a' : A⦄ (s : R a a'), P0 a = P0 a')
(P2 : Π⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t'), e_closure.elim P1 t = e_closure.elim P1 t')
⦃a a' : A⦄ ⦃t t' : T a a'⦄ (q : Q t t')
: square (ap02 (elim P0 P1 P2) (incl2 q)) (P2 q) (elim_inclt P2 t) (elim_inclt P2 t') :=
begin
rewrite [↑[incl2,elim],ap_eq_of_con_inv_eq_idp],
xrewrite [eq_top_of_square (elim_incl2 P0 P1 (elim_1 A R Q P P0 P1 P2) (Qmk R q))],
xrewrite [{simple_two_quotient.elim_inclt (elim_1 A R Q P P0 P1 P2)
(t ⬝r t'⁻¹ʳ)}
idpath (ap_con (simple_two_quotient.elim P0 P1 (elim_1 A R Q P P0 P1 P2))
(inclt t) (inclt t')⁻¹ ⬝
(simple_two_quotient.elim_inclt (elim_1 A R Q P P0 P1 P2) t ◾
(ap_inv (simple_two_quotient.elim P0 P1 (elim_1 A R Q P P0 P1 P2))
(inclt t') ⬝
inverse2 (simple_two_quotient.elim_inclt (elim_1 A R Q P P0 P1 P2) t')))),▸*],
rewrite [-con.assoc _ _ (con_inv_eq_idp _),-con.assoc _ _ (_ ◾ _),con.assoc _ _ (ap_con _ _ _),
con.left_inv,↑whisker_left,con2_con_con2,-con.assoc (ap_inv _ _)⁻¹,
con.left_inv,+idp_con,eq_of_con_inv_eq_idp_con2],
xrewrite [to_left_inv !eq_equiv_con_inv_eq_idp (P2 q)],
apply top_deg_square
end
end
end two_quotient
attribute two_quotient.incl0 [constructor]
attribute two_quotient.rec two_quotient.elim [unfold 8] [recursor 8]
--attribute two_quotient.elim_type [unfold 9]
attribute two_quotient.rec_on two_quotient.elim_on [unfold 5]
--attribute two_quotient.elim_type_on [unfold 6]