Metamath Proof Explorer


Theorem zeroopropdlem

Description: Lemma for zeroopropd . (Contributed by Zhi Wang, 26-Oct-2025)

Ref Expression
Hypotheses initopropd.1
|- ( ph -> ( Homf ` C ) = ( Homf ` D ) )
initopropd.2
|- ( ph -> ( comf ` C ) = ( comf ` D ) )
initopropdlem.1
|- ( ph -> -. C e. _V )
Assertion zeroopropdlem
|- ( ph -> ( ZeroO ` C ) = ( ZeroO ` D ) )

Proof

Step Hyp Ref Expression
1 initopropd.1
 |-  ( ph -> ( Homf ` C ) = ( Homf ` D ) )
2 initopropd.2
 |-  ( ph -> ( comf ` C ) = ( comf ` D ) )
3 initopropdlem.1
 |-  ( ph -> -. C e. _V )
4 zeroofn
 |-  ZeroO Fn Cat
5 ssv
 |-  Cat C_ _V
6 simpr
 |-  ( ( ph /\ D e. Cat ) -> D e. Cat )
7 eqid
 |-  ( Base ` D ) = ( Base ` D )
8 eqid
 |-  ( Hom ` D ) = ( Hom ` D )
9 6 7 8 zerooval
 |-  ( ( ph /\ D e. Cat ) -> ( ZeroO ` D ) = ( ( InitO ` D ) i^i ( TermO ` D ) ) )
10 1 2 3 initopropdlem
 |-  ( ph -> ( InitO ` C ) = ( InitO ` D ) )
11 fvprc
 |-  ( -. C e. _V -> ( InitO ` C ) = (/) )
12 3 11 syl
 |-  ( ph -> ( InitO ` C ) = (/) )
13 10 12 eqtr3d
 |-  ( ph -> ( InitO ` D ) = (/) )
14 13 adantr
 |-  ( ( ph /\ D e. Cat ) -> ( InitO ` D ) = (/) )
15 1 2 3 termopropdlem
 |-  ( ph -> ( TermO ` C ) = ( TermO ` D ) )
16 fvprc
 |-  ( -. C e. _V -> ( TermO ` C ) = (/) )
17 3 16 syl
 |-  ( ph -> ( TermO ` C ) = (/) )
18 15 17 eqtr3d
 |-  ( ph -> ( TermO ` D ) = (/) )
19 18 adantr
 |-  ( ( ph /\ D e. Cat ) -> ( TermO ` D ) = (/) )
20 14 19 ineq12d
 |-  ( ( ph /\ D e. Cat ) -> ( ( InitO ` D ) i^i ( TermO ` D ) ) = ( (/) i^i (/) ) )
21 inidm
 |-  ( (/) i^i (/) ) = (/)
22 20 21 eqtrdi
 |-  ( ( ph /\ D e. Cat ) -> ( ( InitO ` D ) i^i ( TermO ` D ) ) = (/) )
23 9 22 eqtrd
 |-  ( ( ph /\ D e. Cat ) -> ( ZeroO ` D ) = (/) )
24 4 3 5 23 initopropdlemlem
 |-  ( ph -> ( ZeroO ` C ) = ( ZeroO ` D ) )