changeset 1431:052f0fca7799

again... gfImage is not strictly positive, because it occurs
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Sun, 02 Jul 2023 00:59:14 +0900
parents f2125be6fec1
children 8da1d318033b
files src/cardinal.agda
diffstat 1 files changed, 78 insertions(+), 66 deletions(-) [+]
line wrap: on
line diff
--- a/src/cardinal.agda	Sat Jul 01 19:37:54 2023 +0900
+++ b/src/cardinal.agda	Sun Jul 02 00:59:14 2023 +0900
@@ -76,6 +76,12 @@
     im00 {x} record { y = y ; ay = ay ; x=fy = x=fy } = subst₂ ( λ j k → j o< k) (trans &iso (sym x=fy)) &iso 
          (c<→o< (subst ( λ k → odef (* b) k) (sym &iso) (iB iab y ay)) )
 
+record IsImage0 (a b : HOD) (f : (x : Ordinal) → odef a x → Ordinal) (x : Ordinal ) : Set n where
+   field
+      y : Ordinal 
+      ay : odef a y
+      x=fy : x ≡ f y ay
+
 record IsInverseImage (a b : Ordinal) (iab : Injection a b ) (x y : Ordinal ) : Set n where
    field
       ax : odef (* a) x
@@ -124,12 +130,12 @@
 Bernstein : {a b : Ordinal } → Injection a b → Injection b a → OrdBijection a b
 Bernstein {a} {b} (f @ record { i→ = fab ; iB = b∋fab ; inject = fab-inject }) ( g @ record { i→ = fba ; iB = a∋fba ; inject = fba-inject })
      = record { 
-         fun←  = λ x lt → h lt ?
-       ; fun→  = λ x lt → h⁻¹ lt ?
-       ; funB  = be74
-       ; funA  = be75
-       ; fiso← = λ x lt → be72 x lt (cc11 (a∋fba x lt) (cc20 lt))
-       ; fiso→ = λ x lt → be73 x lt (cc10 (b∋fab x lt) (cc21 lt))
+         fun←  = λ x lt → h lt (cc0 x)
+       ; fun→  = λ x lt → h⁻¹ lt (cc1 x)
+       ; funB  = λ x lt → be74 x lt (cc0 x)
+       ; funA  = λ x lt → be75 x lt (cc1 x)
+       ; fiso← = λ x lt → be72 x lt (cc1 x)
+       ; fiso→ = λ x lt → be73 x lt (cc0 x)
        }
  where
       gf : Injection a a
@@ -209,17 +215,20 @@
       be16 {x} lt with subst (λ k → odef k x) *iso lt
       ... | ⟪ ax , ncn ⟫ = nimg ax ncn
 
-      nimg1 : {x : Ordinal} (ax : odef (* a) x) → (ncn : ¬ gfImage x) → IsImage b a g x
-      nimg1 {x} ax ncn = nimg ax ncn
+      FA : (x : Ordinal) → (ax : gfImage x) → Ordinal
+      FA x ax = fab x (a∋gfImage ax)
 
-      cc11-case2 : {x : Ordinal} (ax : odef (* a) x) → (ncn : ¬ gfImage x) 
-          → ¬ odef (Image (& UC) (Injection-⊆ UC⊆a f)) (g⁻¹ ax (nimg ax ncn))
-      cc11-case2 {x} ax ncn record { y = y ; ay = ay ; x=fy = x=fy } = ncn ( subst (λ k → gfImage k) be113 (UC∋gf ay) ) where
-                   be113 : fba (fab y (UC⊆a ay)) (b∋fab y (UC⊆a ay)) ≡ x
-                   be113 = begin
-                      fba (fab y (UC⊆a ay)) (b∋fab y (UC⊆a ay)) ≡⟨ fba-eq (sym x=fy)  ⟩
-                      fba (g⁻¹ ax (nimg ax ncn) ) (b∋g⁻¹ ax (nimg ax ncn) ) ≡⟨ g⁻¹-iso ax (nimg ax ncn) ⟩
-                      x ∎ where open ≡-Reasoning
+      cc11-case2 : {x : Ordinal} (ax : odef (* a) x) 
+          → (ncn : ¬ gfImage x) 
+          → ¬ IsImage0 UC (* b) (λ x ax → fab x (a∋gfImage ax))  (g⁻¹ ax (nimg ax ncn))
+      cc11-case2 {x} ax ncn record { y = y ; ay = ay ; x=fy = x=fy } with nimg ax ncn
+      ... | record { y = y1 ; ay = ay1 ; x=fy = x=fy1 } = ncn ( subst (λ k → gfImage k) be113 
+                                            (next-gf record { y = y ; ay = (a∋gfImage ay) ; x=fy = refl } ay ) )  where
+               be113 : fba (fab y (a∋gfImage ay)) (b∋fab y (a∋gfImage ay)) ≡ x
+               be113 = begin
+                    fba (fab y (a∋gfImage ay)) (b∋fab y (a∋gfImage ay)) ≡⟨ fba-eq (sym x=fy)  ⟩
+                    fba y1 ay1 ≡⟨ sym (x=fy1) ⟩
+                    x ∎ where open ≡-Reasoning
 
       be10 : Injection (& a-UC) (b - (& (Image (& UC) (Injection-⊆ UC⊆a f) )) ) -- g⁻¹ x
       be10 = record { i→ = λ x lt → g⁻¹ (be15 lt) (be16 lt) ; iB = be17 ; inject = be18 } where
@@ -248,9 +257,11 @@
       be60 {b} {x} bx ncn = ⟪ bx , subst (λ k → ¬ odef k x ) (sym *iso) ncn ⟫
 
       cc10-case2 : {x : Ordinal } → (bx : odef (* b) x )
-         → (x₁ : ¬ odef (Image (& UC) (Injection-⊆ UC⊆a f)) x )
-         → ¬ gfImage (be13 x (subst (λ k → odef k x) (sym *iso) (be60 bx x₁)))
-      cc10-case2 = ?
+         → ¬ IsImage0 UC (* b) (λ x ax → fab x (a∋gfImage ax))  x
+         → ¬ gfImage (fba x bx)
+      cc10-case2 {x} bx nix (a-g ax ¬ib) = ¬ib record { y = _ ; ay = bx ; x=fy = refl }
+      cc10-case2 {x} bx nix (next-gf record { y = y ; ay = ay ; x=fy = x=fy } gfy) 
+           = nix record { y = _ ; ay = gfy ; x=fy = inject g _ _ bx (b∋fab y (a∋gfImage gfy)) (trans x=fy (fba-eq (fab-eq refl))) }
 
       be11 : Injection  (b - (& (Image (& UC) (Injection-⊆ UC⊆a f) ))) (& a-UC)   -- g x
       be11 = record { i→ = be13 ; iB = be14 ; inject = ? } where
@@ -293,11 +304,20 @@
             ... | next-gf record { y = y ; ay = ay ; x=fy = x=fy } gfiy 
                    = fab x (subst (λ k → odef (* a) k) (sym x=fy) (a∋fba _ (b∋fab y ay) ))
 
+      fU1 : (x : Ordinal) → odef UC x → Ordinal
+      fU1 x gfx = fab x (a∋gfImage gfx)
+
       --   f (C n) → g (f (C n) ) ≡ C (suc i)
       Uf : (x : Ordinal) → odef (* (& (Image (& UC) (Injection-⊆ UC⊆a f)))) x → Ordinal
       Uf x lt with subst (λ k → odef k x ) *iso lt
       ... | record { y = y ; ay = ay ; x=fy = x=fy } = y
 
+      b∋Uf1 : (x : Ordinal) → IsImage0 UC (* b) FA x → odef (* b) x
+      b∋Uf1 x record { y = y ; ay = ay ; x=fy = x=fy } = subst (λ k → odef (* b) k ) (sym x=fy) (b∋fab y (a∋gfImage ay))
+
+      Uf1 : (x : Ordinal) → IsImage0 UC (* b) FA x → Ordinal
+      Uf1 x lt = fba x (b∋Uf1 x lt) 
+
       be04 : {x : Ordinal } →  (cx : odef (* (& UC)) x) → odef (* (& (Image (& UC) (Injection-⊆ UC⊆a f)))) (fU x cx)
       be04 {x} cx = subst (λ k → odef k (fU x cx) ) (sym *iso) be06 where
             be02 : gfImage x
@@ -338,23 +358,23 @@
          → (ux : odef (* (& UC)) (Uf x cx)) → fU ( Uf x cx ) ux  ≡ x
       UC-iso11 x cx ux = subst (λ k → fU (Uf x cx) k ≡ x) ( HE.≅-to-≡ ( ∋-irr {* (& UC)} {_} (be08 cx) ux)) (UC-iso1 x cx)
 
-      CC0 : (x : Ordinal) → (bx : odef (* a) x)  → Set n
-      CC0 x ax =  gfImage x ∨ (¬ gfImage x) 
+      CC0 : (x : Ordinal) → Set n
+      CC0 x =  gfImage x ∨ (¬ gfImage x) 
 
-      CC1 : (x : Ordinal) → (bx : odef (* b) x) → Set n
-      CC1 x bx =  gfImage (fba x bx) ∨  (¬ gfImage (fba x bx) )
+      CC1 : (x : Ordinal) → Set n
+      CC1 x =  IsImage0 UC (* b) FA x ∨  (¬ IsImage0 UC (* b) FA x) 
 
-      cc0 : (x : Ordinal) → CC0 x ?
+      cc0 : (x : Ordinal) → CC0 x 
       cc0 x = ODC.p∨¬p O (gfImage x) 
 
-      cc1 : (x : Ordinal) → (bx : odef (* b) x) → CC1 x ?
-      cc1 x bx = ODC.p∨¬p O (gfImage (fba x bx) )
+      cc1 : (x : Ordinal) → CC1 x 
+      cc1 x = ODC.p∨¬p O (IsImage0 UC (* b) FA x) 
 
-      cc20 : {x : Ordinal } → (lt : odef (* b) x) → CC0 (fba x lt ) ?
-      cc20 = ?
+      cc20 : {x : Ordinal } → (lt : odef (* b) x) → CC0 (fba x lt ) 
+      cc20 {x} lt = cc0 (fba x lt)
 
-      cc21 : {x : Ordinal } → (lt : odef (* a) x) → CC1 (fab x lt ) ?
-      cc21 = ?
+      cc21 : {x : Ordinal } → (lt : odef (* a) x) → CC1 (fab x lt ) 
+      cc21 {x} lt = cc1 (fab x lt)
 
       --
       --  h    : * a  → * b
@@ -368,55 +388,44 @@
       --
       --  otherwise not strict positive on gfImage error will happen
 
-      h : {x : Ordinal } → (ax : odef (* a) x) → CC0 x ax → Ordinal
-      h {x} ax (case1 cn)  = fU x (subst (λ k → odef k x ) (sym *iso) cn )
+      h : {x : Ordinal } → (ax : odef (* a) x) → CC0 x → Ordinal
+      h {x} ax (case1 cn)  = fU1 x cn
       h {x} ax (case2 ncn) = g⁻¹ ax (nimg ax ncn)
 
-      h⁻¹ : {x : Ordinal } → (bx : odef (* b) x) → CC1 x bx → Ordinal
-      h⁻¹ {x} bx ( case1 cn)  = Uf x ?                    --   x ≡ f y
+      h⁻¹ : {x : Ordinal } → (bx : odef (* b) x) → CC1 x → Ordinal
+      h⁻¹ {x} bx ( case1 cn)  = Uf1 x cn                    --   x ≡ f y
       h⁻¹ {x} bx ( case2 ncn) = fba x bx
 
-      cc10 : {x : Ordinal} → (bx : odef (* b) x) → (cc1 : CC1 x bx) → CC0 (h⁻¹ bx cc1 ) ?
-      cc10 {x} bx (case1 x₁) = case1 ? -- (subst₂ (λ j k → odef j k ) *iso refl (be08 (subst (λ k → odef k x) (sym *iso) x₁)))
-      cc10 {x} bx (case2 x₁) = case2 ? -- (cc10-case2 bx ? ) 
-
-      cc11 : {x : Ordinal} → (ax : odef (* a) x) → (cc0 : CC0 x ax) → CC1 (h ax cc0 ) ?
-      cc11 {x} ax (case1 x₁) = case1 ? -- (subst₂ (λ j k → odef j k ) *iso refl (be04 (subst (λ k → odef k x) (sym *iso) x₁)))
-      cc11 {x} ax (case2 x₁) = case2 ? -- (cc11-case2 ax x₁)
+      cc10 : {x : Ordinal} → (bx : odef (* b) x) → (cc1 : CC1 x ) → CC0 (h⁻¹ bx cc1 ) 
+      cc10 {x} bx (case1 record { y = y ; ay = ay ; x=fy = x=fy }) = 
+          case1 (next-gf record { y = _ ; ay = a∋gfImage ay ; x=fy = fba-eq x=fy } ay )
+      cc10 {x} bx (case2 x₁) = case2 (cc10-case2 bx x₁ ) 
 
-      be70 : (x : Ordinal) (lt : odef (* a) x) → (or : gfImage x ∨ (¬ gfImage x )) → odef (* b) (h lt or )
-      be70 x ax ( case1 cn ) = be03 (subst (λ k → odef k x) (sym *iso) cn) where    -- make the same condition for Uf
-           be03 : (cn : odef (* (& UC)) x) → odef (* b) (fU x cn )
-           be03 cn with subst (λ k → odef k x) *iso cn 
-           ... | a-g ax ¬ib = b∋fab x ax
-           ... | next-gf record { y = y ; ay = ay ; x=fy = x=fy } gfiy = b∋fab x
-                 (subst (odef (* a)) (sym x=fy) (a∋fba (fab y ay) (b∋fab y ay)))
-      be70 x ax ( case2 ncn ) = ? -- proj1 (subst₂ (λ j k → odef j k ) *iso refl (iB be10 x (subst (λ k → odef k x ) (sym *iso) ⟪ ax , ncn ⟫ ))) 
+      cc11 : {x : Ordinal} → (ax : odef (* a) x) → (cc0 : CC0 x ) → CC1 (h ax cc0 ) 
+      cc11 {x} ax (case1 x₁) = case1 record {y = _ ; ay = x₁ ; x=fy = refl } 
+      cc11 {x} ax (case2 x₁) = case2 (cc11-case2 ax x₁)
 
-      be71 :  (x : Ordinal) (bx : odef (* b) x) 
-             → (or : (odef ( Image (& UC) (Injection-⊆ UC⊆a f)) x) ∨ ( ¬ (odef ( Image (& UC) (Injection-⊆ UC⊆a f)) x)   ))
-             → odef (* a) (h⁻¹ bx ? )
-      be71  x bx ( case1 cn ) = be03 (subst (λ k → odef k x) (sym *iso) cn) where
-           be03 : (cn : odef (* (& (Image (& UC) (Injection-⊆ UC⊆a f)))) x) → odef (* a) (Uf x cn )
-           be03 cn with subst (λ k → odef k x ) *iso cn
-           ... | record { y = y ; ay = ay ; x=fy = x=fy } = UC⊆a ay
-      be71 x bx ( case2 ncn ) = proj1 (subst₂ (λ j k → odef j k ) *iso refl (iB be11 x (subst (λ k → odef k x) (sym *iso) (be60 bx ncn)) ))   
+      be70 : (x : Ordinal) (lt : odef (* a) x) → (or :  CC0 x ) → odef (* b) (h lt or )
+      be70 x ax ( case1 cn ) = b∋fab x (a∋gfImage cn)
+      be70 x ax ( case2 ncn ) = b∋g⁻¹ ax (nimg ax ncn)
+
+      be71 :  (x : Ordinal) (bx : odef (* b) x) → (or : CC1 x) → odef (* a) (h⁻¹ bx or )
+      be71  x bx ( case1 cn ) = subst (λ k → odef (* a) k) (fba-eq refl) (a∋fba x bx  )
+      be71 x bx ( case2 ncn ) = a∋fba x bx 
 
       be71-1 :  (x : Ordinal) (bx : odef (* b) x) 
              → (or : (odef ( Image (& UC) (Injection-⊆ UC⊆a f)) x)) 
              → gfImage (h⁻¹ bx (case1 ? ) )
-      be71-1 x bx cn = subst₂ (λ j k → odef j k ) *iso refl (be08 (subst (λ k → odef k x) (sym *iso) cn))  
+      be71-1 x bx cn = ? -- subst₂ (λ j k → odef j k ) *iso refl (be08 (subst (λ k → odef k x) (sym *iso) cn))  
 
       be70-1 : (x : Ordinal) (lt : odef (* a) x) → (or : gfImage x ∨ (¬ gfImage x )) → odef ( Image (& UC) (Injection-⊆ UC⊆a f)) (h lt or ) 
       be70-1 = ?
 
-      be74 : (x : Ordinal) (ax : odef (* a) x) → odef (* b) (h ax (cc0 x))
-      be74 x ax with cc0 x
-      ... | case1 lt1 = ?
-      ... | case2 lt1 with iB be10 ? ?
+      be74 : (x : Ordinal) (ax : odef (* a) x) (cc0 : CC0 x) → odef (* b) (h ax cc0 )
+      be74 x ax with cc0 
       ... | t = ?
 
-      be75 : (x : Ordinal) (bx : odef (* b) x) → odef (* a) (h⁻¹ bx ? )
+      be75 : (x : Ordinal) (bx : odef (* b) x) → (cc1 : CC1 x) → odef (* a) (h⁻¹ bx cc1 )
       be75 x lt  = ?
 
       fba-image : {x : Ordinal } → (bx : odef (* b) x) → odef (Image b g) (fba x bx)
@@ -425,12 +434,15 @@
       ImageUnique : {a b x : Ordinal } → {F : Injection a b} → (i j : odef (Image a F) x ) → IsImage.y i ≡ IsImage.y j
       ImageUnique {a} {b} {x} {F} i j = inject F _ _ (IsImage.ay i) (IsImage.ay j) (trans (sym (IsImage.x=fy i)) (IsImage.x=fy j))
 
-      be72 :  (x : Ordinal) (bx : odef (* b) x) → (cc1 : CC1 x bx) →  h (be71 x bx ? ) (cc10 bx ? ) ≡ x
-      be72 x bx = ?
+      be72 :  (x : Ordinal) (bx : odef (* b) x) → (cc1 : CC1 x ) →  h (be75 x bx cc1) (cc0 (h⁻¹ bx cc1)) ≡ x
+      be72 x bx (case1 x₁) with cc0 (Uf1 x x₁)
+      ... | t = ?
+      be72 x bx (case2 x₁) = ?
 
 
-      be73 :  (x : Ordinal) (ax : odef (* a) x) → (cc0 : CC0 x ax ) →  h⁻¹ (be70 x ax cc0) ? ≡ x
+      be73 :  (x : Ordinal) (ax : odef (* a) x) → (cc0 : CC0 x ) →  h⁻¹ (be74 x ax cc0) (cc1 (h ax cc0)) ≡ x
       be73 x ax (case1 x₁) = ?
+      be73 x ax (case2 x₁) = ?
 
 
 _c<_ : ( A B : HOD ) → Set n