Metamath Proof Explorer


Theorem cntzval

Description: Definition substitution for a centralizer. (Contributed by Stefan O'Rear, 5-Sep-2015)

Ref Expression
Hypotheses cntzfval.b 𝐵 = ( Base ‘ 𝑀 )
cntzfval.p + = ( +g𝑀 )
cntzfval.z 𝑍 = ( Cntz ‘ 𝑀 )
Assertion cntzval ( 𝑆𝐵 → ( 𝑍𝑆 ) = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )

Proof

Step Hyp Ref Expression
1 cntzfval.b 𝐵 = ( Base ‘ 𝑀 )
2 cntzfval.p + = ( +g𝑀 )
3 cntzfval.z 𝑍 = ( Cntz ‘ 𝑀 )
4 1 2 3 cntzfval ( 𝑀 ∈ V → 𝑍 = ( 𝑠 ∈ 𝒫 𝐵 ↦ { 𝑥𝐵 ∣ ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ) )
5 4 fveq1d ( 𝑀 ∈ V → ( 𝑍𝑆 ) = ( ( 𝑠 ∈ 𝒫 𝐵 ↦ { 𝑥𝐵 ∣ ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ) ‘ 𝑆 ) )
6 1 fvexi 𝐵 ∈ V
7 6 elpw2 ( 𝑆 ∈ 𝒫 𝐵𝑆𝐵 )
8 raleq ( 𝑠 = 𝑆 → ( ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) ↔ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) ) )
9 8 rabbidv ( 𝑠 = 𝑆 → { 𝑥𝐵 ∣ ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )
10 eqid ( 𝑠 ∈ 𝒫 𝐵 ↦ { 𝑥𝐵 ∣ ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ) = ( 𝑠 ∈ 𝒫 𝐵 ↦ { 𝑥𝐵 ∣ ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )
11 6 rabex { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ∈ V
12 9 10 11 fvmpt ( 𝑆 ∈ 𝒫 𝐵 → ( ( 𝑠 ∈ 𝒫 𝐵 ↦ { 𝑥𝐵 ∣ ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ) ‘ 𝑆 ) = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )
13 7 12 sylbir ( 𝑆𝐵 → ( ( 𝑠 ∈ 𝒫 𝐵 ↦ { 𝑥𝐵 ∣ ∀ 𝑦𝑠 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ) ‘ 𝑆 ) = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )
14 5 13 sylan9eq ( ( 𝑀 ∈ V ∧ 𝑆𝐵 ) → ( 𝑍𝑆 ) = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )
15 0fv ( ∅ ‘ 𝑆 ) = ∅
16 fvprc ( ¬ 𝑀 ∈ V → ( Cntz ‘ 𝑀 ) = ∅ )
17 3 16 syl5eq ( ¬ 𝑀 ∈ V → 𝑍 = ∅ )
18 17 fveq1d ( ¬ 𝑀 ∈ V → ( 𝑍𝑆 ) = ( ∅ ‘ 𝑆 ) )
19 ssrab2 { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ⊆ 𝐵
20 fvprc ( ¬ 𝑀 ∈ V → ( Base ‘ 𝑀 ) = ∅ )
21 1 20 syl5eq ( ¬ 𝑀 ∈ V → 𝐵 = ∅ )
22 19 21 sseqtrid ( ¬ 𝑀 ∈ V → { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ⊆ ∅ )
23 ss0 ( { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } ⊆ ∅ → { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } = ∅ )
24 22 23 syl ( ¬ 𝑀 ∈ V → { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } = ∅ )
25 15 18 24 3eqtr4a ( ¬ 𝑀 ∈ V → ( 𝑍𝑆 ) = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )
26 25 adantr ( ( ¬ 𝑀 ∈ V ∧ 𝑆𝐵 ) → ( 𝑍𝑆 ) = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )
27 14 26 pm2.61ian ( 𝑆𝐵 → ( 𝑍𝑆 ) = { 𝑥𝐵 ∣ ∀ 𝑦𝑆 ( 𝑥 + 𝑦 ) = ( 𝑦 + 𝑥 ) } )