Metamath Proof Explorer


Theorem resscntz

Description: Centralizer in a substructure. (Contributed by Mario Carneiro, 3-Oct-2015)

Ref Expression
Hypotheses resscntz.p 𝐻 = ( 𝐺s 𝐴 )
resscntz.z 𝑍 = ( Cntz ‘ 𝐺 )
resscntz.y 𝑌 = ( Cntz ‘ 𝐻 )
Assertion resscntz ( ( 𝐴𝑉𝑆𝐴 ) → ( 𝑌𝑆 ) = ( ( 𝑍𝑆 ) ∩ 𝐴 ) )

Proof

Step Hyp Ref Expression
1 resscntz.p 𝐻 = ( 𝐺s 𝐴 )
2 resscntz.z 𝑍 = ( Cntz ‘ 𝐺 )
3 resscntz.y 𝑌 = ( Cntz ‘ 𝐻 )
4 eqid ( Base ‘ 𝐻 ) = ( Base ‘ 𝐻 )
5 4 3 cntzrcl ( 𝑥 ∈ ( 𝑌𝑆 ) → ( 𝐻 ∈ V ∧ 𝑆 ⊆ ( Base ‘ 𝐻 ) ) )
6 5 simprd ( 𝑥 ∈ ( 𝑌𝑆 ) → 𝑆 ⊆ ( Base ‘ 𝐻 ) )
7 eqid ( Base ‘ 𝐺 ) = ( Base ‘ 𝐺 )
8 1 7 ressbasss ( Base ‘ 𝐻 ) ⊆ ( Base ‘ 𝐺 )
9 6 8 sstrdi ( 𝑥 ∈ ( 𝑌𝑆 ) → 𝑆 ⊆ ( Base ‘ 𝐺 ) )
10 9 a1i ( ( 𝐴𝑉𝑆𝐴 ) → ( 𝑥 ∈ ( 𝑌𝑆 ) → 𝑆 ⊆ ( Base ‘ 𝐺 ) ) )
11 elinel1 ( 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) → 𝑥 ∈ ( 𝑍𝑆 ) )
12 7 2 cntzrcl ( 𝑥 ∈ ( 𝑍𝑆 ) → ( 𝐺 ∈ V ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) )
13 12 simprd ( 𝑥 ∈ ( 𝑍𝑆 ) → 𝑆 ⊆ ( Base ‘ 𝐺 ) )
14 11 13 syl ( 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) → 𝑆 ⊆ ( Base ‘ 𝐺 ) )
15 14 a1i ( ( 𝐴𝑉𝑆𝐴 ) → ( 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) → 𝑆 ⊆ ( Base ‘ 𝐺 ) ) )
16 elin ( 𝑥 ∈ ( 𝐴 ∩ ( Base ‘ 𝐺 ) ) ↔ ( 𝑥𝐴𝑥 ∈ ( Base ‘ 𝐺 ) ) )
17 1 7 ressbas ( 𝐴𝑉 → ( 𝐴 ∩ ( Base ‘ 𝐺 ) ) = ( Base ‘ 𝐻 ) )
18 17 eleq2d ( 𝐴𝑉 → ( 𝑥 ∈ ( 𝐴 ∩ ( Base ‘ 𝐺 ) ) ↔ 𝑥 ∈ ( Base ‘ 𝐻 ) ) )
19 16 18 bitr3id ( 𝐴𝑉 → ( ( 𝑥𝐴𝑥 ∈ ( Base ‘ 𝐺 ) ) ↔ 𝑥 ∈ ( Base ‘ 𝐻 ) ) )
20 eqid ( +g𝐺 ) = ( +g𝐺 )
21 1 20 ressplusg ( 𝐴𝑉 → ( +g𝐺 ) = ( +g𝐻 ) )
22 21 oveqd ( 𝐴𝑉 → ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑥 ( +g𝐻 ) 𝑦 ) )
23 21 oveqd ( 𝐴𝑉 → ( 𝑦 ( +g𝐺 ) 𝑥 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) )
24 22 23 eqeq12d ( 𝐴𝑉 → ( ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ↔ ( 𝑥 ( +g𝐻 ) 𝑦 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) ) )
25 24 ralbidv ( 𝐴𝑉 → ( ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ↔ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐻 ) 𝑦 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) ) )
26 19 25 anbi12d ( 𝐴𝑉 → ( ( ( 𝑥𝐴𝑥 ∈ ( Base ‘ 𝐺 ) ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ↔ ( 𝑥 ∈ ( Base ‘ 𝐻 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐻 ) 𝑦 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) ) ) )
27 26 ad2antrr ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → ( ( ( 𝑥𝐴𝑥 ∈ ( Base ‘ 𝐺 ) ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ↔ ( 𝑥 ∈ ( Base ‘ 𝐻 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐻 ) 𝑦 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) ) ) )
28 anass ( ( ( 𝑥𝐴𝑥 ∈ ( Base ‘ 𝐺 ) ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ↔ ( 𝑥𝐴 ∧ ( 𝑥 ∈ ( Base ‘ 𝐺 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ) )
29 27 28 bitr3di ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → ( ( 𝑥 ∈ ( Base ‘ 𝐻 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐻 ) 𝑦 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) ) ↔ ( 𝑥𝐴 ∧ ( 𝑥 ∈ ( Base ‘ 𝐺 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ) ) )
30 ssin ( ( 𝑆𝐴𝑆 ⊆ ( Base ‘ 𝐺 ) ) ↔ 𝑆 ⊆ ( 𝐴 ∩ ( Base ‘ 𝐺 ) ) )
31 17 sseq2d ( 𝐴𝑉 → ( 𝑆 ⊆ ( 𝐴 ∩ ( Base ‘ 𝐺 ) ) ↔ 𝑆 ⊆ ( Base ‘ 𝐻 ) ) )
32 30 31 syl5bb ( 𝐴𝑉 → ( ( 𝑆𝐴𝑆 ⊆ ( Base ‘ 𝐺 ) ) ↔ 𝑆 ⊆ ( Base ‘ 𝐻 ) ) )
33 32 biimpd ( 𝐴𝑉 → ( ( 𝑆𝐴𝑆 ⊆ ( Base ‘ 𝐺 ) ) → 𝑆 ⊆ ( Base ‘ 𝐻 ) ) )
34 33 impl ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → 𝑆 ⊆ ( Base ‘ 𝐻 ) )
35 eqid ( +g𝐻 ) = ( +g𝐻 )
36 4 35 3 elcntz ( 𝑆 ⊆ ( Base ‘ 𝐻 ) → ( 𝑥 ∈ ( 𝑌𝑆 ) ↔ ( 𝑥 ∈ ( Base ‘ 𝐻 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐻 ) 𝑦 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) ) ) )
37 34 36 syl ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → ( 𝑥 ∈ ( 𝑌𝑆 ) ↔ ( 𝑥 ∈ ( Base ‘ 𝐻 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐻 ) 𝑦 ) = ( 𝑦 ( +g𝐻 ) 𝑥 ) ) ) )
38 elin ( 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) ↔ ( 𝑥 ∈ ( 𝑍𝑆 ) ∧ 𝑥𝐴 ) )
39 38 biancomi ( 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) ↔ ( 𝑥𝐴𝑥 ∈ ( 𝑍𝑆 ) ) )
40 7 20 2 elcntz ( 𝑆 ⊆ ( Base ‘ 𝐺 ) → ( 𝑥 ∈ ( 𝑍𝑆 ) ↔ ( 𝑥 ∈ ( Base ‘ 𝐺 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ) )
41 40 adantl ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → ( 𝑥 ∈ ( 𝑍𝑆 ) ↔ ( 𝑥 ∈ ( Base ‘ 𝐺 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ) )
42 41 anbi2d ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → ( ( 𝑥𝐴𝑥 ∈ ( 𝑍𝑆 ) ) ↔ ( 𝑥𝐴 ∧ ( 𝑥 ∈ ( Base ‘ 𝐺 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ) ) )
43 39 42 syl5bb ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → ( 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) ↔ ( 𝑥𝐴 ∧ ( 𝑥 ∈ ( Base ‘ 𝐺 ) ∧ ∀ 𝑦𝑆 ( 𝑥 ( +g𝐺 ) 𝑦 ) = ( 𝑦 ( +g𝐺 ) 𝑥 ) ) ) ) )
44 29 37 43 3bitr4d ( ( ( 𝐴𝑉𝑆𝐴 ) ∧ 𝑆 ⊆ ( Base ‘ 𝐺 ) ) → ( 𝑥 ∈ ( 𝑌𝑆 ) ↔ 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) ) )
45 44 ex ( ( 𝐴𝑉𝑆𝐴 ) → ( 𝑆 ⊆ ( Base ‘ 𝐺 ) → ( 𝑥 ∈ ( 𝑌𝑆 ) ↔ 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) ) ) )
46 10 15 45 pm5.21ndd ( ( 𝐴𝑉𝑆𝐴 ) → ( 𝑥 ∈ ( 𝑌𝑆 ) ↔ 𝑥 ∈ ( ( 𝑍𝑆 ) ∩ 𝐴 ) ) )
47 46 eqrdv ( ( 𝐴𝑉𝑆𝐴 ) → ( 𝑌𝑆 ) = ( ( 𝑍𝑆 ) ∩ 𝐴 ) )