Theorem gsumress 13468

Description: The group sum in a substructure is the same as the group sum in the original structure. The only requirement on the substructure is that it contain the identity element; neither G nor H need be groups. (Contributed by Mario Carneiro, 19-Dec-2014.) (Revised by Mario Carneiro, 30-Apr-2015.)

Hypotheses

Ref	Expression
gsumress.b	|- B = ( Base ` G )
gsumress.o	|- .+ = ( +g ` G )
gsumress.h	|- H = ( G ↾s S )
gsumress.g	|- ( ph -> G e. V )
gsumress.a	|- ( ph -> A e. X )
gsumress.s	|- ( ph -> S C_ B )
gsumress.f	|- ( ph -> F : A --> S )
gsumress.z	|- ( ph -> .0. e. S )
gsumress.c	|- ( ( ph /\ x e. B ) -> ( ( .0. .+ x ) = x /\ ( x .+ .0. ) = x ) )

Assertion

Ref	Expression
gsumress	|- ( ph -> ( G gsumg F ) = ( H gsumg F ) )

Distinct variable groups:   x, B   x, G   ph, x   x, S   x, H   x, .+   x, .0.

Allowed substitution hints:   A( x)   F( x)   V( x)   X( x)

Proof of Theorem gsumress

Dummy variables m n y z are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		gsumress.g	. . . . . . . . . 10 |- ( ph -> G e. V )
2		gsumress.b	. . . . . . . . . . 11 |- B = ( Base ` G )
3		eqid 2229	. . . . . . . . . . 11 |- ( 0g ` G ) = ( 0g ` G )
4		gsumress.o	. . . . . . . . . . 11 |- .+ = ( +g ` G )
5		eqid 2229	. . . . . . . . . . 11 |- { y e. B | A. x e. B ( ( y .+ x ) = x /\ ( x .+ y ) = x ) } = { y e. B | A. x e. B ( ( y .+ x ) = x /\ ( x .+ y ) = x ) }
6	2, 3, 4, 5	mgmidsssn0 13457	. . . . . . . . . 10 |- ( G e. V -> { y e. B | A. x e. B ( ( y .+ x ) = x /\ ( x .+ y ) = x ) } C_ { ( 0g ` G ) } )
7	1, 6	syl 14	. . . . . . . . 9 |- ( ph -> { y e. B | A. x e. B ( ( y .+ x ) = x /\ ( x .+ y ) = x ) } C_ { ( 0g ` G ) } )
8		oveq1 6020	. . . . . . . . . . . 12 |- ( y = .0. -> ( y .+ x ) = ( .0. .+ x ) )
9	8	eqeq1d 2238	. . . . . . . . . . 11 |- ( y = .0. -> ( ( y .+ x ) = x <-> ( .0. .+ x ) = x ) )
10	9	ovanraleqv 6037	. . . . . . . . . 10 |- ( y = .0. -> ( A. x e. B ( ( y .+ x ) = x /\ ( x .+ y ) = x ) <-> A. x e. B ( ( .0. .+ x ) = x /\ ( x .+ .0. ) = x ) ) )
11		gsumress.s	. . . . . . . . . . 11 |- ( ph -> S C_ B )
12		gsumress.z	. . . . . . . . . . 11 |- ( ph -> .0. e. S )
13	11, 12	sseldd 3226	. . . . . . . . . 10 |- ( ph -> .0. e. B )
14		gsumress.c	. . . . . . . . . . 11 |- ( ( ph /\ x e. B ) -> ( ( .0. .+ x ) = x /\ ( x .+ .0. ) = x ) )
15	14	ralrimiva 2603	. . . . . . . . . 10 |- ( ph -> A. x e. B ( ( .0. .+ x ) = x /\ ( x .+ .0. ) = x ) )
16	10, 13, 15	elrabd 2962	. . . . . . . . 9 |- ( ph -> .0. e. { y e. B | A. x e. B ( ( y .+ x ) = x /\ ( x .+ y ) = x ) } )
17	7, 16	sseldd 3226	. . . . . . . 8 |- ( ph -> .0. e. { ( 0g ` G ) } )
18		elsni 3685	. . . . . . . 8 |- ( .0. e. { ( 0g ` G ) } -> .0. = ( 0g ` G ) )
19	17, 18	syl 14	. . . . . . 7 |- ( ph -> .0. = ( 0g ` G ) )
20		gsumress.h	. . . . . . . . . . . . 13 |- H = ( G ↾s S )
21	20	a1i 9	. . . . . . . . . . . 12 |- ( ph -> H = ( G ↾s S ) )
22	2	a1i 9	. . . . . . . . . . . 12 |- ( ph -> B = ( Base ` G ) )
23	21, 22, 1, 11	ressbas2d 13141	. . . . . . . . . . 11 |- ( ph -> S = ( Base ` H ) )
24	23, 12	basmexd 13133	. . . . . . . . . 10 |- ( ph -> H e. _V )
25		eqid 2229	. . . . . . . . . . 11 |- ( Base ` H ) = ( Base ` H )
26		eqid 2229	. . . . . . . . . . 11 |- ( 0g ` H ) = ( 0g ` H )
27		eqid 2229	. . . . . . . . . . 11 |- ( +g ` H ) = ( +g ` H )
28		eqid 2229	. . . . . . . . . . 11 |- { y e. ( Base ` H ) | A. x e. ( Base ` H ) ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) } = { y e. ( Base ` H ) | A. x e. ( Base ` H ) ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) }
29	25, 26, 27, 28	mgmidsssn0 13457	. . . . . . . . . 10 |- ( H e. _V -> { y e. ( Base ` H ) | A. x e. ( Base ` H ) ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) } C_ { ( 0g ` H ) } )
30	24, 29	syl 14	. . . . . . . . 9 |- ( ph -> { y e. ( Base ` H ) | A. x e. ( Base ` H ) ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) } C_ { ( 0g ` H ) } )
31	9	ovanraleqv 6037	. . . . . . . . . . 11 |- ( y = .0. -> ( A. x e. S ( ( y .+ x ) = x /\ ( x .+ y ) = x ) <-> A. x e. S ( ( .0. .+ x ) = x /\ ( x .+ .0. ) = x ) ) )
32	11	sselda 3225	. . . . . . . . . . . . 13 |- ( ( ph /\ x e. S ) -> x e. B )
33	32, 14	syldan 282	. . . . . . . . . . . 12 |- ( ( ph /\ x e. S ) -> ( ( .0. .+ x ) = x /\ ( x .+ .0. ) = x ) )
34	33	ralrimiva 2603	. . . . . . . . . . 11 |- ( ph -> A. x e. S ( ( .0. .+ x ) = x /\ ( x .+ .0. ) = x ) )
35	31, 12, 34	elrabd 2962	. . . . . . . . . 10 |- ( ph -> .0. e. { y e. S | A. x e. S ( ( y .+ x ) = x /\ ( x .+ y ) = x ) } )
36	4	a1i 9	. . . . . . . . . . . . . . . 16 |- ( ph -> .+ = ( +g ` G ) )
37		basfn 13131	. . . . . . . . . . . . . . . . . 18 |- Base Fn _V
38		funfvex 5652	. . . . . . . . . . . . . . . . . . 19 |- ( ( Fun Base /\ H e. dom Base ) -> ( Base ` H ) e. _V )
39	38	funfni 5429	. . . . . . . . . . . . . . . . . 18 |- ( ( Base Fn _V /\ H e. _V ) -> ( Base ` H ) e. _V )
40	37, 24, 39	sylancr 414	. . . . . . . . . . . . . . . . 17 |- ( ph -> ( Base ` H ) e. _V )
41	23, 40	eqeltrd 2306	. . . . . . . . . . . . . . . 16 |- ( ph -> S e. _V )
42	21, 36, 41, 1	ressplusgd 13202	. . . . . . . . . . . . . . 15 |- ( ph -> .+ = ( +g ` H ) )
43	42	oveqd 6030	. . . . . . . . . . . . . 14 |- ( ph -> ( y .+ x ) = ( y ( +g ` H ) x ) )
44	43	eqeq1d 2238	. . . . . . . . . . . . 13 |- ( ph -> ( ( y .+ x ) = x <-> ( y ( +g ` H ) x ) = x ) )
45	42	oveqd 6030	. . . . . . . . . . . . . 14 |- ( ph -> ( x .+ y ) = ( x ( +g ` H ) y ) )
46	45	eqeq1d 2238	. . . . . . . . . . . . 13 |- ( ph -> ( ( x .+ y ) = x <-> ( x ( +g ` H ) y ) = x ) )
47	44, 46	anbi12d 473	. . . . . . . . . . . 12 |- ( ph -> ( ( ( y .+ x ) = x /\ ( x .+ y ) = x ) <-> ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) ) )
48	23, 47	raleqbidv 2744	. . . . . . . . . . 11 |- ( ph -> ( A. x e. S ( ( y .+ x ) = x /\ ( x .+ y ) = x ) <-> A. x e. ( Base ` H ) ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) ) )
49	23, 48	rabeqbidv 2795	. . . . . . . . . 10 |- ( ph -> { y e. S | A. x e. S ( ( y .+ x ) = x /\ ( x .+ y ) = x ) } = { y e. ( Base ` H ) | A. x e. ( Base ` H ) ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) } )
50	35, 49	eleqtrd 2308	. . . . . . . . 9 |- ( ph -> .0. e. { y e. ( Base ` H ) | A. x e. ( Base ` H ) ( ( y ( +g ` H ) x ) = x /\ ( x ( +g ` H ) y ) = x ) } )
51	30, 50	sseldd 3226	. . . . . . . 8 |- ( ph -> .0. e. { ( 0g ` H ) } )
52		elsni 3685	. . . . . . . 8 |- ( .0. e. { ( 0g ` H ) } -> .0. = ( 0g ` H ) )
53	51, 52	syl 14	. . . . . . 7 |- ( ph -> .0. = ( 0g ` H ) )
54	19, 53	eqtr3d 2264	. . . . . 6 |- ( ph -> ( 0g ` G ) = ( 0g ` H ) )
55	54	eqeq2d 2241	. . . . 5 |- ( ph -> ( z = ( 0g ` G ) <-> z = ( 0g ` H ) ) )
56	55	anbi2d 464	. . . 4 |- ( ph -> ( ( A = (/) /\ z = ( 0g ` G ) ) <-> ( A = (/) /\ z = ( 0g ` H ) ) ) )
57	42	seqeq2d 10706	. . . . . . . . 9 |- ( ph -> seq m ( .+ , F ) = seq m ( ( +g ` H ) , F ) )
58	57	fveq1d 5637	. . . . . . . 8 |- ( ph -> ( seq m ( .+ , F ) ` n ) = ( seq m ( ( +g ` H ) , F ) ` n ) )
59	58	eqeq2d 2241	. . . . . . 7 |- ( ph -> ( z = ( seq m ( .+ , F ) ` n ) <-> z = ( seq m ( ( +g ` H ) , F ) ` n ) ) )
60	59	anbi2d 464	. . . . . 6 |- ( ph -> ( ( A = ( m ... n ) /\ z = ( seq m ( .+ , F ) ` n ) ) <-> ( A = ( m ... n ) /\ z = ( seq m ( ( +g ` H ) , F ) ` n ) ) ) )
61	60	rexbidv 2531	. . . . 5 |- ( ph -> ( E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( .+ , F ) ` n ) ) <-> E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( ( +g ` H ) , F ) ` n ) ) ) )
62	61	exbidv 1871	. . . 4 |- ( ph -> ( E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( .+ , F ) ` n ) ) <-> E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( ( +g ` H ) , F ) ` n ) ) ) )
63	56, 62	orbi12d 798	. . 3 |- ( ph -> ( ( ( A = (/) /\ z = ( 0g ` G ) ) \/ E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( .+ , F ) ` n ) ) ) <-> ( ( A = (/) /\ z = ( 0g ` H ) ) \/ E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( ( +g ` H ) , F ) ` n ) ) ) ) )
64	63	iotabidv 5307	. 2 |- ( ph -> ( iota z ( ( A = (/) /\ z = ( 0g ` G ) ) \/ E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( .+ , F ) ` n ) ) ) ) = ( iota z ( ( A = (/) /\ z = ( 0g ` H ) ) \/ E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( ( +g ` H ) , F ) ` n ) ) ) ) )
65		gsumress.a	. . 3 |- ( ph -> A e. X )
66		gsumress.f	. . . 4 |- ( ph -> F : A --> S )
67	66, 11	fssd 5492	. . 3 |- ( ph -> F : A --> B )
68	2, 3, 4, 1, 65, 67	igsumval 13463	. 2 |- ( ph -> ( G gsumg F ) = ( iota z ( ( A = (/) /\ z = ( 0g ` G ) ) \/ E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( .+ , F ) ` n ) ) ) ) )
69	23	feq3d 5468	. . . 4 |- ( ph -> ( F : A --> S <-> F : A --> ( Base ` H ) ) )
70	66, 69	mpbid 147	. . 3 |- ( ph -> F : A --> ( Base ` H ) )
71	25, 26, 27, 24, 65, 70	igsumval 13463	. 2 |- ( ph -> ( H gsumg F ) = ( iota z ( ( A = (/) /\ z = ( 0g ` H ) ) \/ E. m E. n e. ( ZZ>= ` m ) ( A = ( m ... n ) /\ z = ( seq m ( ( +g ` H ) , F ) ` n ) ) ) ) )
72	64, 68, 71	3eqtr4d 2272	1 |- ( ph -> ( G gsumg F ) = ( H gsumg F ) )

Syntax hints:   -> wi 4   /\ wa 104   \/ wo 713   = wceq 1395   E.wex 1538   e. wcel 2200   A.wral 2508   E.wrex 2509   {crab 2512   _Vcvv 2800   C_ wss 3198   (/)c0 3492   {csn 3667   iotacio 5282   Fn wfn 5319   -->wf 5320   ` cfv 5324  (class class class)co 6013   ZZ>=cuz 9745   ...cfz 10233   seqcseq 10699   Basecbs 13072   ↾_s cress 13073   +g cplusg 13150   0gc0g 13329   gsum_g cgsu 13330

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-coll 4202  ax-sep 4205  ax-pow 4262  ax-pr 4297  ax-un 4528  ax-setind 4633  ax-cnex 8113  ax-resscn 8114  ax-1cn 8115  ax-1re 8116  ax-icn 8117  ax-addcl 8118  ax-addrcl 8119  ax-mulcl 8120  ax-addcom 8122  ax-addass 8124  ax-i2m1 8127  ax-0lt1 8128  ax-0id 8130  ax-rnegex 8131  ax-pre-ltirr 8134  ax-pre-ltadd 8138

This theorem depends on definitions:  df-bi 117  df-3or 1003  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-nel 2496  df-ral 2513  df-rex 2514  df-reu 2515  df-rmo 2516  df-rab 2517  df-v 2802  df-sbc 3030  df-csb 3126  df-dif 3200  df-un 3202  df-in 3204  df-ss 3211  df-nul 3493  df-pw 3652  df-sn 3673  df-pr 3674  df-op 3676  df-uni 3892  df-int 3927  df-iun 3970  df-br 4087  df-opab 4149  df-mpt 4150  df-id 4388  df-xp 4729  df-rel 4730  df-cnv 4731  df-co 4732  df-dm 4733  df-rn 4734  df-res 4735  df-ima 4736  df-iota 5284  df-fun 5326  df-fn 5327  df-f 5328  df-f1 5329  df-fo 5330  df-f1o 5331  df-fv 5332  df-riota 5966  df-ov 6016  df-oprab 6017  df-mpo 6018  df-recs 6466  df-frec 6552  df-pnf 8206  df-mnf 8207  df-ltxr 8209  df-neg 8343  df-inn 9134  df-2 9192  df-z 9470  df-uz 9746  df-seqfrec 10700  df-ndx 13075  df-slot 13076  df-base 13078  df-sets 13079  df-iress 13080  df-plusg 13163  df-0g 13331  df-igsum 13332

This theorem is referenced by:  gsumsubm  13567