Metamath Proof Explorer


Definition df-dprd

Description: Define the internal direct product of a family of subgroups. (Contributed by Mario Carneiro, 21-Apr-2016) (Revised by AV, 11-Jul-2019)

Ref Expression
Assertion df-dprd DProd = ( 𝑔 ∈ Grp , 𝑠 ∈ { ∣ ( : dom ⟶ ( SubGrp ‘ 𝑔 ) ∧ ∀ 𝑥 ∈ dom ( ∀ 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) ) ∧ ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) } ) ) } ↦ ran ( 𝑓 ∈ { X 𝑥 ∈ dom 𝑠 ( 𝑠𝑥 ) ∣ finSupp ( 0g𝑔 ) } ↦ ( 𝑔 Σg 𝑓 ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cdprd DProd
1 vg 𝑔
2 cgrp Grp
3 vs 𝑠
4 vh
5 4 cv
6 5 cdm dom
7 csubg SubGrp
8 1 cv 𝑔
9 8 7 cfv ( SubGrp ‘ 𝑔 )
10 6 9 5 wf : dom ⟶ ( SubGrp ‘ 𝑔 )
11 vx 𝑥
12 vy 𝑦
13 11 cv 𝑥
14 13 csn { 𝑥 }
15 6 14 cdif ( dom ∖ { 𝑥 } )
16 13 5 cfv ( 𝑥 )
17 ccntz Cntz
18 8 17 cfv ( Cntz ‘ 𝑔 )
19 12 cv 𝑦
20 19 5 cfv ( 𝑦 )
21 20 18 cfv ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) )
22 16 21 wss ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) )
23 22 12 15 wral 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) )
24 cmrc mrCls
25 9 24 cfv ( mrCls ‘ ( SubGrp ‘ 𝑔 ) )
26 5 15 cima ( “ ( dom ∖ { 𝑥 } ) )
27 26 cuni ( “ ( dom ∖ { 𝑥 } ) )
28 27 25 cfv ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) )
29 16 28 cin ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) )
30 c0g 0g
31 8 30 cfv ( 0g𝑔 )
32 31 csn { ( 0g𝑔 ) }
33 29 32 wceq ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) }
34 23 33 wa ( ∀ 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) ) ∧ ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) } )
35 34 11 6 wral 𝑥 ∈ dom ( ∀ 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) ) ∧ ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) } )
36 10 35 wa ( : dom ⟶ ( SubGrp ‘ 𝑔 ) ∧ ∀ 𝑥 ∈ dom ( ∀ 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) ) ∧ ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) } ) )
37 36 4 cab { ∣ ( : dom ⟶ ( SubGrp ‘ 𝑔 ) ∧ ∀ 𝑥 ∈ dom ( ∀ 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) ) ∧ ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) } ) ) }
38 vf 𝑓
39 3 cv 𝑠
40 39 cdm dom 𝑠
41 13 39 cfv ( 𝑠𝑥 )
42 11 40 41 cixp X 𝑥 ∈ dom 𝑠 ( 𝑠𝑥 )
43 cfsupp finSupp
44 5 31 43 wbr finSupp ( 0g𝑔 )
45 44 4 42 crab { X 𝑥 ∈ dom 𝑠 ( 𝑠𝑥 ) ∣ finSupp ( 0g𝑔 ) }
46 cgsu Σg
47 38 cv 𝑓
48 8 47 46 co ( 𝑔 Σg 𝑓 )
49 38 45 48 cmpt ( 𝑓 ∈ { X 𝑥 ∈ dom 𝑠 ( 𝑠𝑥 ) ∣ finSupp ( 0g𝑔 ) } ↦ ( 𝑔 Σg 𝑓 ) )
50 49 crn ran ( 𝑓 ∈ { X 𝑥 ∈ dom 𝑠 ( 𝑠𝑥 ) ∣ finSupp ( 0g𝑔 ) } ↦ ( 𝑔 Σg 𝑓 ) )
51 1 3 2 37 50 cmpo ( 𝑔 ∈ Grp , 𝑠 ∈ { ∣ ( : dom ⟶ ( SubGrp ‘ 𝑔 ) ∧ ∀ 𝑥 ∈ dom ( ∀ 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) ) ∧ ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) } ) ) } ↦ ran ( 𝑓 ∈ { X 𝑥 ∈ dom 𝑠 ( 𝑠𝑥 ) ∣ finSupp ( 0g𝑔 ) } ↦ ( 𝑔 Σg 𝑓 ) ) )
52 0 51 wceq DProd = ( 𝑔 ∈ Grp , 𝑠 ∈ { ∣ ( : dom ⟶ ( SubGrp ‘ 𝑔 ) ∧ ∀ 𝑥 ∈ dom ( ∀ 𝑦 ∈ ( dom ∖ { 𝑥 } ) ( 𝑥 ) ⊆ ( ( Cntz ‘ 𝑔 ) ‘ ( 𝑦 ) ) ∧ ( ( 𝑥 ) ∩ ( ( mrCls ‘ ( SubGrp ‘ 𝑔 ) ) ‘ ( “ ( dom ∖ { 𝑥 } ) ) ) ) = { ( 0g𝑔 ) } ) ) } ↦ ran ( 𝑓 ∈ { X 𝑥 ∈ dom 𝑠 ( 𝑠𝑥 ) ∣ finSupp ( 0g𝑔 ) } ↦ ( 𝑔 Σg 𝑓 ) ) )