diff equalizer.agda @ 253:24e83b8b81be

fix
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Wed, 11 Sep 2013 20:26:48 +0900
parents e0835b8dd51b
children 45b81fcb8a64
line wrap: on
line diff
--- a/equalizer.agda	Mon Sep 09 16:15:09 2013 +0900
+++ b/equalizer.agda	Wed Sep 11 20:26:48 2013 +0900
@@ -30,6 +30,7 @@
    equalizer : Hom A c a
    equalizer = e
 
+
 --
 -- Burroni's Flat Equational Definition of Equalizer
 --
@@ -116,7 +117,7 @@
              ≈⟨ cdr assoc ⟩
                     e o (( h-1  o  h)  o k eqa j eq  ) 
              ≈⟨ cdr (car h-1h=1 )  ⟩
-                    e o (id1 A c  o k eqa j eq  ) 
+                    e o (id c  o k eqa j eq  ) 
              ≈⟨ cdr idL  ⟩
                     e o  k eqa j eq  
              ≈⟨ ek=h eqa ⟩
@@ -139,7 +140,7 @@
              ≈⟨ assoc  ⟩
                    (h o   h-1 ) o j 
              ≈⟨ car hh-1=1  ⟩
-                   id1 A c' o j 
+                   id c' o j 
              ≈⟨ idL ⟩
                    j

@@ -194,23 +195,23 @@
 e'←e {c} {c'} {a} {b} {f} {g} {e} {e'} eqa eqa' keqa = let open ≈-Reasoning (A) in begin
                  e o c-iso-r eqa eqa' keqa 
               ≈⟨⟩
-                 e  o  k keqa (id1 A c') ( f1=g1 (fe=ge eqa') (id1 A c') )
+                 e  o  k keqa (id c') ( f1=g1 (fe=ge eqa') (id c') )
               ≈↑⟨ car  (ek=h eqa' ) ⟩
-                 ( equalizer eqa'  o k eqa' e (fe=ge eqa) ) o  k keqa (id1 A c') ( f1=g1 (fe=ge eqa') (id1 A c') )
+                 ( equalizer eqa'  o k eqa' e (fe=ge eqa) ) o  k keqa (id c') ( f1=g1 (fe=ge eqa') (id c') )
               ≈⟨⟩
-                 ( e'  o k eqa' e (fe=ge eqa) ) o  k keqa (id1 A c') ( f1=g1 (fe=ge eqa') (id1 A c') )
+                 ( e'  o k eqa' e (fe=ge eqa) ) o  k keqa (id c') ( f1=g1 (fe=ge eqa') (id c') )
               ≈↑⟨ assoc ⟩
-                 e'  o (( k eqa' e (fe=ge eqa) ) o  k keqa (id1 A c') ( f1=g1 (fe=ge eqa') (id1 A c') ) )
+                 e'  o (( k eqa' e (fe=ge eqa) ) o  k keqa (id c') ( f1=g1 (fe=ge eqa') (id c') ) )
               ≈⟨⟩
-                 e'  o (equalizer keqa  o  k keqa (id1 A c') ( f1=g1 (fe=ge eqa') (id1 A c') ) )
+                 e'  o (equalizer keqa  o  k keqa (id c') ( f1=g1 (fe=ge eqa') (id c') ) )
               ≈⟨ cdr ( ek=h keqa )  ⟩
-                 e'  o id1 A c'
+                 e'  o id c'
               ≈⟨ idR ⟩
                  e'

 
---    e←e' e'←e = e
---    e'←e e←e = e'  is enough for isomorphism but we want to prove l o r = id also.
+--    e←e' e'←e e = e
+--    e'←e e←e e' = e'  is enough for isomorphism but we can prove l o r = id also.
 
 c-iso→ : { c c' a b : Obj A } {f g : Hom A a b } → {e : Hom A c a } {e' : Hom A c' a} ( eqa : Equalizer A e f g) → ( eqa' :  Equalizer A e' f g )
       →  ( keqa : Equalizer A (k eqa' e (fe=ge eqa)) (A [ f o e' ])  (A [ g o e' ]) )
@@ -218,9 +219,9 @@
 c-iso→ {c} {c'} {a} {b} {f} {g} eqa eqa' keqa = let open ≈-Reasoning (A) in begin
                  c-iso-l eqa eqa' keqa o c-iso-r eqa eqa' keqa
               ≈⟨⟩
-                 equalizer keqa  o  k keqa (id1 A c') ( f1=g1 (fe=ge eqa') (id1 A c') )
+                 equalizer keqa  o  k keqa (id c') ( f1=g1 (fe=ge eqa') (id c') )
               ≈⟨ ek=h keqa ⟩
-                 id1 A c'
+                 id c'

 
 c-iso← : { c c' a b : Obj A } {f g : Hom A a b } → {e : Hom A c a } {e' : Hom A c' a} ( eqa : Equalizer A e f g) → ( eqa' :  Equalizer A e' f g )
@@ -230,26 +231,26 @@
 c-iso← {c} {c'} {a} {b} {f} {g} {e} {e'} eqa eqa' keqa keqa'  = let open ≈-Reasoning (A) in begin
                  c-iso-r eqa eqa' keqa o c-iso-l eqa eqa' keqa
               ≈⟨⟩
-                 k keqa (id1 A c') ( f1=g1 (fe=ge eqa') (id1 A c') ) o k eqa' e (fe=ge eqa )
+                 k keqa (id c') ( f1=g1 (fe=ge eqa') (id c') ) o k eqa' e (fe=ge eqa )
               ≈⟨⟩
                  equalizer keqa'  o k eqa' e (fe=ge eqa )
               ≈⟨ cdr ( begin
                      k eqa' e (fe=ge eqa )
                    ≈⟨ uniqueness eqa' ( begin
-                       e' o k keqa' (id1 A c) (f1=g1 (fe=ge eqa) (id1 A c))
+                       e' o k keqa' (id c) (f1=g1 (fe=ge eqa) (id c))
                    ≈↑⟨ car (e'←e eqa eqa' keqa ) ⟩
-                        ( e  o equalizer keqa' ) o k keqa' (id1 A c) (f1=g1 (fe=ge eqa) (id1 A c))
+                        ( e  o equalizer keqa' ) o k keqa' (id c) (f1=g1 (fe=ge eqa) (id c))
                    ≈↑⟨ assoc ⟩
-                         e  o ( equalizer keqa'  o k keqa' (id1 A c) (f1=g1 (fe=ge eqa) (id1 A c)))
+                         e  o ( equalizer keqa'  o k keqa' (id c) (f1=g1 (fe=ge eqa) (id c)))
                    ≈⟨ cdr ( ek=h keqa' ) ⟩
-                         e  o id1 A c
+                         e  o id c
                    ≈⟨ idR ⟩
                        e
                    ∎ )⟩
-                     k keqa' (id1 A c) ( f1=g1 (fe=ge eqa) (id1 A c) )
+                     k keqa' (id c) ( f1=g1 (fe=ge eqa) (id c) )
               ∎ )⟩
-                 equalizer keqa'  o k keqa' (id1 A c) ( f1=g1 (fe=ge eqa) (id1 A c) ) ≈⟨ ek=h keqa' ⟩
-                 id1 A c
+                 equalizer keqa'  o k keqa' (id c) ( f1=g1 (fe=ge eqa) (id c) ) ≈⟨ ek=h keqa' ⟩
+                 id c

 
 
@@ -292,9 +293,9 @@
      lemma-b3 : {a b d : Obj A} (f : Hom A a b ) { h : Hom A d a } → A [ A [ equalizer (eqa f f ) o k (eqa f f) (id1 A a) (f1=f1 f) ] ≈ id1 A a  ]
      lemma-b3 {a} {b} {d} f {h} = let open ≈-Reasoning (A) in
              begin
-                  equalizer (eqa f f) o k (eqa f f) (id1 A a) (f1=f1 f)
+                  equalizer (eqa f f) o k (eqa f f) (id a) (f1=f1 f)
              ≈⟨ ek=h (eqa f f )  ⟩
-                  id1 A a
+                  id a

      lemma-equ4 :  {a b c d : Obj A}  → (f : Hom A a b) → (g : Hom A a b ) → (h : Hom A d a ) →
                       A [ A [ f o A [ h o equalizer (eqa (A [ f o h ]) (A [ g o h ])) ] ] ≈ A [ g o A [ h o equalizer (eqa (A [ f o h ]) (A [ g o h ])) ] ] ]
@@ -329,13 +330,13 @@
                                                                             k (eqa {a} {b} {c} f' f' {e} ) (id1 A a)  (f1=f1 f') ]
      cong-δ1 {a} {b} {c} {e} {f} {f'} f=f' =  let open ≈-Reasoning (A) in
              begin
-                 k (eqa {a} {b} {c} f  f  {e} ) (id1 A a)  (f1=f1 f) 
+                 k (eqa {a} {b} {c} f  f  {e} ) (id a)  (f1=f1 f) 
              ≈⟨  uniqueness (eqa f f) ( begin
-                 e o k (eqa {a} {b} {c} f' f' {e} ) (id1 A a)  (f1=f1 f') 
+                 e o k (eqa {a} {b} {c} f' f' {e} ) (id a)  (f1=f1 f') 
              ≈⟨ ek=h (eqa {a} {b} {c} f' f' {e} ) ⟩
-                 id1 A a
+                 id a
              ∎ )⟩
-                 k (eqa {a} {b} {c} f' f' {e} ) (id1 A a)  (f1=f1 f') 
+                 k (eqa {a} {b} {c} f' f' {e} ) (id a)  (f1=f1 f') 

 
      lemma-b2 :  {d : Obj A} {h : Hom A d a} → A [
@@ -362,19 +363,19 @@
              ≈⟨ car ((uniqueness (eqa f g) ( begin
                          equalizer (eqa f g) o j 
                 ≈↑⟨ idR  ⟩
-                         (equalizer (eqa f g) o j )  o id1 A d
-                ≈⟨⟩         -- here we decide e (fej) (gej)' is id1 A d
+                         (equalizer (eqa f g) o j )  o id d
+                ≈⟨⟩         -- here we decide e (fej) (gej)' is id d
                         ((equalizer (eqa f g) o j) o equalizer (eqa (f o equalizer (eqa f g {e}) o j) (g o equalizer (eqa f g {e}) o j)))
              ∎ ))) ⟩
                     j o k (eqa (( f o ( equalizer (eqa f g) o j ) )) (( f o ( equalizer (eqa f g) o j ) ))) (id1 A d) (f1=f1 (( f o ( equalizer (eqa f g) o j ) ))) 
              ≈⟨ cdr ((uniqueness (eqa (( f o ( equalizer (eqa f g) o j ) )) (( f o ( equalizer (eqa f g) o j ) ))) ( begin
-                     equalizer (eqa (f o equalizer (eqa f g {e} ) o j) (f o equalizer (eqa f g {e}) o j))  o id1 A d
+                     equalizer (eqa (f o equalizer (eqa f g {e} ) o j) (f o equalizer (eqa f g {e}) o j))  o id d
                 ≈⟨ idR ⟩
                      equalizer (eqa (f o equalizer (eqa f g {e}) o j) (f o equalizer (eqa f g {e}) o j))  
-                ≈⟨⟩         -- here we decide e (fej) (fej)' is id1 A d
-                    id1 A d
+                ≈⟨⟩         -- here we decide e (fej) (fej)' is id d
+                    id d
              ∎ ))) ⟩
-                    j o id1 A d
+                    j o id d
                 ≈⟨ idR ⟩
                     j

@@ -401,17 +402,17 @@
              begin
                  α bur f g e o k1 h eq 
              ≈⟨⟩
-                 α bur f g e o ( γ bur {a} {b} {c} f g h o δ bur {d} {b} {d} (id1 A d) (f o h) )
+                 α bur f g e o ( γ bur {a} {b} {c} f g h o δ bur {d} {b} {d} (id d) (f o h) )
              ≈⟨ assoc ⟩
-                 ( α bur f g e o  γ bur {a} {b} {c} f g h ) o δ bur {d} {b} {d} (id1 A d) (f o h) 
+                 ( α bur f g e o  γ bur {a} {b} {c} f g h ) o δ bur {d} {b} {d} (id d) (f o h) 
              ≈⟨ car (b2 bur) ⟩
-                  ( h o ( α bur ( f o h ) ( g o h ) (id1 A d))) o δ bur {d} {b} {d} (id1 A d) (f o h) 
+                  ( h o ( α bur ( f o h ) ( g o h ) (id d))) o δ bur {d} {b} {d} (id d) (f o h) 
              ≈↑⟨ assoc ⟩
-                   h o ((( α bur ( f o h ) ( g o h ) (id1 A d) )) o δ bur {d} {b} {d} (id1 A d) (f o h)  )
+                   h o ((( α bur ( f o h ) ( g o h ) (id d) )) o δ bur {d} {b} {d} (id d) (f o h)  )
              ≈↑⟨ cdr ( car ( cong-α bur eq)) ⟩
-                   h o ((( α bur ( f o h ) ( f o h ) (id1 A d)))o δ bur {d} {b} {d} (id1 A d) (f o h)  )
-             ≈⟨ cdr (b3 bur {d} {b} {d} (f  o h) {id1 A d} ) ⟩
-                   h o id1 A d
+                   h o ((( α bur ( f o h ) ( f o h ) (id d)))o δ bur {d} {b} {d} (id d) (f o h)  )
+             ≈⟨ cdr (b3 bur {d} {b} {d} (f  o h) {id d} ) ⟩
+                   h o id d
              ≈⟨ idR ⟩
                  h 

@@ -421,11 +422,11 @@
              begin
                 k1 {d} h eq
              ≈⟨⟩
-                γ bur {a} {b} {c} f g h o δ bur {d} {b} {d} (id1 A d) (f o h)
+                γ bur {a} {b} {c} f g h o δ bur {d} {b} {d} (id d) (f o h)
              ≈↑⟨ car (cong-γ bur {a} {b} {c} {d} ek=h ) ⟩
-                γ bur f g (A [ α bur f g e o k' ]) o δ bur {d} {b} {d} (id1 A d) (f o h)
+                γ bur f g (A [ α bur f g e o k' ]) o δ bur {d} {b} {d} (id d) (f o h)
              ≈↑⟨ cdr (cong-δ bur (resp ek=h refl-hom )) ⟩
-                γ bur f g (A [ α bur f g e o k' ]) o δ bur {d} {b} {d} (id1 A d) ( f o ( α bur f g e o k') ) 
+                γ bur f g (A [ α bur f g e o k' ]) o δ bur {d} {b} {d} (id d) ( f o ( α bur f g e o k') ) 
              ≈⟨ b4 bur ⟩
                  k'