changeset 53:b4530a807918

start adjunction
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Tue, 23 Jul 2013 16:36:31 +0900
parents 0fc0dbda7b55
children 5d2a33bb1291
files universal-mapping.agda
diffstat 1 files changed, 31 insertions(+), 0 deletions(-) [+]
line wrap: on
line diff
--- a/universal-mapping.agda	Tue Jul 23 16:18:21 2013 +0900
+++ b/universal-mapping.agda	Tue Jul 23 16:36:31 2013 +0900
@@ -296,3 +296,34 @@
        ∎ )
     myIsNTrans : IsNTrans B B ( F' ○ U ) identityFunctor ε
     myIsNTrans = record { naturality = naturality }
+
+------
+--
+--   Adjunction Construction from Universal Mapping
+--
+-----
+
+UMAdjunction : {c₁ c₂ ℓ c₁' c₂' ℓ' : Level} (A : Category c₁ c₂ ℓ) (B : Category c₁' c₂' ℓ') 
+                 ( U : Functor B A )
+                 ( F' : Obj A -> Obj B )
+                 ( η' : (a : Obj A) -> Hom A a ( FObj U (F' a) ) ) ->
+       (um : UniversalMapping A B U F' η' )  -> 
+              Adjunction A B U (FunctorF A B U F' η' um) (nat-η A B U F' η' um) (nat-ε A B U F' η' um)
+UMAdjunction A B U F' η' um = record {
+           isAdjunction = record {
+               adjoint1 = adjoint1 ; 
+               adjoint2 = adjoint2
+           } 
+       } where
+          F : Functor A B
+          F = FunctorF A B U F' η' um
+          η : NTrans A A identityFunctor ( U ○  F ) 
+          η = nat-η A B U F' η' um
+          ε : NTrans B B  ( F ○  U ) identityFunctor 
+          ε = nat-ε A B U F' η' um
+          adjoint1 :   { b : Obj B } ->
+                     A [ A [ ( FMap U ( TMap ε b ))  o ( TMap η ( FObj U b )) ]  ≈ id1 A (FObj U b) ]
+          adjoint1 = ?
+          adjoint2 :   {a : Obj A} ->
+                     B [ B [ ( TMap ε ( FObj F a ))  o ( FMap F ( TMap η a )) ]  ≈ id1 B (FObj F a) ]
+          adjoint2 = ?