Metamath Proof Explorer


Theorem fullresc

Description: The category formed by structure restriction is the same as the category restriction. (Contributed by Mario Carneiro, 5-Jan-2017)

Ref Expression
Hypotheses fullsubc.b
|- B = ( Base ` C )
fullsubc.h
|- H = ( Homf ` C )
fullsubc.c
|- ( ph -> C e. Cat )
fullsubc.s
|- ( ph -> S C_ B )
fullsubc.d
|- D = ( C |`s S )
fullsubc.e
|- E = ( C |`cat ( H |` ( S X. S ) ) )
Assertion fullresc
|- ( ph -> ( ( Homf ` D ) = ( Homf ` E ) /\ ( comf ` D ) = ( comf ` E ) ) )

Proof

Step Hyp Ref Expression
1 fullsubc.b
 |-  B = ( Base ` C )
2 fullsubc.h
 |-  H = ( Homf ` C )
3 fullsubc.c
 |-  ( ph -> C e. Cat )
4 fullsubc.s
 |-  ( ph -> S C_ B )
5 fullsubc.d
 |-  D = ( C |`s S )
6 fullsubc.e
 |-  E = ( C |`cat ( H |` ( S X. S ) ) )
7 eqid
 |-  ( Hom ` C ) = ( Hom ` C )
8 4 adantr
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> S C_ B )
9 simprl
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> x e. S )
10 8 9 sseldd
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> x e. B )
11 simprr
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> y e. S )
12 8 11 sseldd
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> y e. B )
13 2 1 7 10 12 homfval
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x H y ) = ( x ( Hom ` C ) y ) )
14 9 11 ovresd
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x ( H |` ( S X. S ) ) y ) = ( x H y ) )
15 2 1 homffn
 |-  H Fn ( B X. B )
16 xpss12
 |-  ( ( S C_ B /\ S C_ B ) -> ( S X. S ) C_ ( B X. B ) )
17 4 4 16 syl2anc
 |-  ( ph -> ( S X. S ) C_ ( B X. B ) )
18 fnssres
 |-  ( ( H Fn ( B X. B ) /\ ( S X. S ) C_ ( B X. B ) ) -> ( H |` ( S X. S ) ) Fn ( S X. S ) )
19 15 17 18 sylancr
 |-  ( ph -> ( H |` ( S X. S ) ) Fn ( S X. S ) )
20 6 1 3 19 4 reschom
 |-  ( ph -> ( H |` ( S X. S ) ) = ( Hom ` E ) )
21 20 oveqdr
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x ( H |` ( S X. S ) ) y ) = ( x ( Hom ` E ) y ) )
22 14 21 eqtr3d
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x H y ) = ( x ( Hom ` E ) y ) )
23 5 1 ressbas2
 |-  ( S C_ B -> S = ( Base ` D ) )
24 4 23 syl
 |-  ( ph -> S = ( Base ` D ) )
25 fvex
 |-  ( Base ` D ) e. _V
26 24 25 eqeltrdi
 |-  ( ph -> S e. _V )
27 5 7 resshom
 |-  ( S e. _V -> ( Hom ` C ) = ( Hom ` D ) )
28 26 27 syl
 |-  ( ph -> ( Hom ` C ) = ( Hom ` D ) )
29 28 oveqdr
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x ( Hom ` C ) y ) = ( x ( Hom ` D ) y ) )
30 13 22 29 3eqtr3rd
 |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x ( Hom ` D ) y ) = ( x ( Hom ` E ) y ) )
31 30 ralrimivva
 |-  ( ph -> A. x e. S A. y e. S ( x ( Hom ` D ) y ) = ( x ( Hom ` E ) y ) )
32 eqid
 |-  ( Hom ` D ) = ( Hom ` D )
33 eqid
 |-  ( Hom ` E ) = ( Hom ` E )
34 6 1 3 19 4 rescbas
 |-  ( ph -> S = ( Base ` E ) )
35 32 33 24 34 homfeq
 |-  ( ph -> ( ( Homf ` D ) = ( Homf ` E ) <-> A. x e. S A. y e. S ( x ( Hom ` D ) y ) = ( x ( Hom ` E ) y ) ) )
36 31 35 mpbird
 |-  ( ph -> ( Homf ` D ) = ( Homf ` E ) )
37 eqid
 |-  ( comp ` C ) = ( comp ` C )
38 5 37 ressco
 |-  ( S e. _V -> ( comp ` C ) = ( comp ` D ) )
39 26 38 syl
 |-  ( ph -> ( comp ` C ) = ( comp ` D ) )
40 6 1 3 19 4 37 rescco
 |-  ( ph -> ( comp ` C ) = ( comp ` E ) )
41 39 40 eqtr3d
 |-  ( ph -> ( comp ` D ) = ( comp ` E ) )
42 41 36 comfeqd
 |-  ( ph -> ( comf ` D ) = ( comf ` E ) )
43 36 42 jca
 |-  ( ph -> ( ( Homf ` D ) = ( Homf ` E ) /\ ( comf ` D ) = ( comf ` E ) ) )