Theorem gaorber 19384

Description: The orbit equivalence relation is an equivalence relation on the target set of the group action. (Contributed by NM, 11-Aug-2009.) (Revised by Mario Carneiro, 13-Jan-2015.)

Hypotheses

Ref	Expression
gaorb.1	⊢ ∼ = {⟨𝑥, 𝑦⟩ ∣ ({𝑥, 𝑦} ⊆ 𝑌 ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦)}
gaorber.2	⊢ 𝑋 = (Base‘𝐺)

Assertion

Ref	Expression
gaorber	⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → ∼ Er 𝑌)

Distinct variable groups:   𝑥,𝑔,𝑦, ⊕   𝑔,𝑋,𝑥,𝑦   𝑥,𝑌,𝑦

Allowed substitution hints:   ∼ (𝑥, 𝑦, 𝑔)   𝐺(𝑥, 𝑦, 𝑔)   𝑌(𝑔)

Proof of Theorem gaorber

Dummy variables ℎ 𝑓 𝑘 𝑢 𝑣 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		gaorb.1	. . . 4 ⊢ ∼ = {⟨𝑥, 𝑦⟩ ∣ ({𝑥, 𝑦} ⊆ 𝑌 ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦)}
2	1	relopabiv 5806	. . 3 ⊢ Rel ∼
3	2	a1i 11	. 2 ⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → Rel ∼ )
4		simpr 489	. . . . 5 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → 𝑢 ∼ 𝑣)
5	1	gaorb 19383	. . . . 5 ⊢ (𝑢 ∼ 𝑣 ↔ (𝑢 ∈ 𝑌 ∧ 𝑣 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑣))
6	4, 5	sylib 221	. . . 4 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → (𝑢 ∈ 𝑌 ∧ 𝑣 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑣))
7	6	simp2d 1160	. . 3 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → 𝑣 ∈ 𝑌)
8	6	simp1d 1159	. . 3 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → 𝑢 ∈ 𝑌)
9	6	simp3d 1161	. . . 4 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑣)
10		simpll 778	. . . . . . 7 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → ⊕ ∈ (𝐺 GrpAct 𝑌))
11		simpr 489	. . . . . . 7 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → ℎ ∈ 𝑋)
12	8	adantr 485	. . . . . . 7 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → 𝑢 ∈ 𝑌)
13	7	adantr 485	. . . . . . 7 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → 𝑣 ∈ 𝑌)
14		gaorber.2	. . . . . . . 8 ⊢ 𝑋 = (Base‘𝐺)
15		eqid 2762	. . . . . . . 8 ⊢ (invg‘𝐺) = (invg‘𝐺)
16	14, 15	gacan 19381	. . . . . . 7 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (ℎ ∈ 𝑋 ∧ 𝑢 ∈ 𝑌 ∧ 𝑣 ∈ 𝑌)) → ((ℎ ⊕ 𝑢) = 𝑣 ↔ (((invg‘𝐺)‘ℎ) ⊕ 𝑣) = 𝑢))
17	10, 11, 12, 13, 16	syl13anc 1398	. . . . . 6 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → ((ℎ ⊕ 𝑢) = 𝑣 ↔ (((invg‘𝐺)‘ℎ) ⊕ 𝑣) = 𝑢))
18		gagrp 19368	. . . . . . . . 9 ⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → 𝐺 ∈ Grp)
19	18	adantr 485	. . . . . . . 8 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → 𝐺 ∈ Grp)
20	14, 15	grpinvcl 19060	. . . . . . . 8 ⊢ ((𝐺 ∈ Grp ∧ ℎ ∈ 𝑋) → ((invg‘𝐺)‘ℎ) ∈ 𝑋)
21	19, 20	sylan 591	. . . . . . 7 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → ((invg‘𝐺)‘ℎ) ∈ 𝑋)
22		oveq1 7419	. . . . . . . . . 10 ⊢ (𝑘 = ((invg‘𝐺)‘ℎ) → (𝑘 ⊕ 𝑣) = (((invg‘𝐺)‘ℎ) ⊕ 𝑣))
23	22	eqeq1d 2764	. . . . . . . . 9 ⊢ (𝑘 = ((invg‘𝐺)‘ℎ) → ((𝑘 ⊕ 𝑣) = 𝑢 ↔ (((invg‘𝐺)‘ℎ) ⊕ 𝑣) = 𝑢))
24	23	rspcev 3580	. . . . . . . 8 ⊢ ((((invg‘𝐺)‘ℎ) ∈ 𝑋 ∧ (((invg‘𝐺)‘ℎ) ⊕ 𝑣) = 𝑢) → ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑢)
25	24	ex 417	. . . . . . 7 ⊢ (((invg‘𝐺)‘ℎ) ∈ 𝑋 → ((((invg‘𝐺)‘ℎ) ⊕ 𝑣) = 𝑢 → ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑢))
26	21, 25	syl 18	. . . . . 6 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → ((((invg‘𝐺)‘ℎ) ⊕ 𝑣) = 𝑢 → ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑢))
27	17, 26	sylbid 243	. . . . 5 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) ∧ ℎ ∈ 𝑋) → ((ℎ ⊕ 𝑢) = 𝑣 → ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑢))
28	27	rexlimdva 3165	. . . 4 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → (∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑣 → ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑢))
29	9, 28	mpd 16	. . 3 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑢)
30	1	gaorb 19383	. . 3 ⊢ (𝑣 ∼ 𝑢 ↔ (𝑣 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑢))
31	7, 8, 29, 30	syl3anbrc 1361	. 2 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∼ 𝑣) → 𝑣 ∼ 𝑢)
32	8	adantrr 729	. . 3 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → 𝑢 ∈ 𝑌)
33		simprr 784	. . . . 5 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → 𝑣 ∼ 𝑤)
34	1	gaorb 19383	. . . . 5 ⊢ (𝑣 ∼ 𝑤 ↔ (𝑣 ∈ 𝑌 ∧ 𝑤 ∈ 𝑌 ∧ ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑤))
35	33, 34	sylib 221	. . . 4 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → (𝑣 ∈ 𝑌 ∧ 𝑤 ∈ 𝑌 ∧ ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑤))
36	35	simp2d 1160	. . 3 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → 𝑤 ∈ 𝑌)
37	9	adantrr 729	. . . 4 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑣)
38	35	simp3d 1161	. . . 4 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑤)
39		reeanv 3236	. . . . 5 ⊢ (∃ℎ ∈ 𝑋 ∃𝑘 ∈ 𝑋 ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤) ↔ (∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑣 ∧ ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑤))
40	18	ad2antrr 738	. . . . . . . . 9 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → 𝐺 ∈ Grp)
41		simprlr 791	. . . . . . . . 9 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → 𝑘 ∈ 𝑋)
42		simprll 790	. . . . . . . . 9 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → ℎ ∈ 𝑋)
43		eqid 2762	. . . . . . . . . 10 ⊢ (+g‘𝐺) = (+g‘𝐺)
44	14, 43	grpcl 19014	. . . . . . . . 9 ⊢ ((𝐺 ∈ Grp ∧ 𝑘 ∈ 𝑋 ∧ ℎ ∈ 𝑋) → (𝑘(+g‘𝐺)ℎ) ∈ 𝑋)
45	40, 41, 42, 44	syl3anc 1397	. . . . . . . 8 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → (𝑘(+g‘𝐺)ℎ) ∈ 𝑋)
46		simpll 778	. . . . . . . . . 10 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → ⊕ ∈ (𝐺 GrpAct 𝑌))
47	32	adantr 485	. . . . . . . . . 10 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → 𝑢 ∈ 𝑌)
48	14, 43	gaass 19373	. . . . . . . . . 10 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑘 ∈ 𝑋 ∧ ℎ ∈ 𝑋 ∧ 𝑢 ∈ 𝑌)) → ((𝑘(+g‘𝐺)ℎ) ⊕ 𝑢) = (𝑘 ⊕ (ℎ ⊕ 𝑢)))
49	46, 41, 42, 47, 48	syl13anc 1398	. . . . . . . . 9 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → ((𝑘(+g‘𝐺)ℎ) ⊕ 𝑢) = (𝑘 ⊕ (ℎ ⊕ 𝑢)))
50		simprrl 792	. . . . . . . . . 10 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → (ℎ ⊕ 𝑢) = 𝑣)
51	50	oveq2d 7428	. . . . . . . . 9 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → (𝑘 ⊕ (ℎ ⊕ 𝑢)) = (𝑘 ⊕ 𝑣))
52		simprrr 793	. . . . . . . . 9 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → (𝑘 ⊕ 𝑣) = 𝑤)
53	49, 51, 52	3eqtrd 2801	. . . . . . . 8 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → ((𝑘(+g‘𝐺)ℎ) ⊕ 𝑢) = 𝑤)
54		oveq1 7419	. . . . . . . . . 10 ⊢ (𝑓 = (𝑘(+g‘𝐺)ℎ) → (𝑓 ⊕ 𝑢) = ((𝑘(+g‘𝐺)ℎ) ⊕ 𝑢))
55	54	eqeq1d 2764	. . . . . . . . 9 ⊢ (𝑓 = (𝑘(+g‘𝐺)ℎ) → ((𝑓 ⊕ 𝑢) = 𝑤 ↔ ((𝑘(+g‘𝐺)ℎ) ⊕ 𝑢) = 𝑤))
56	55	rspcev 3580	. . . . . . . 8 ⊢ (((𝑘(+g‘𝐺)ℎ) ∈ 𝑋 ∧ ((𝑘(+g‘𝐺)ℎ) ⊕ 𝑢) = 𝑤) → ∃𝑓 ∈ 𝑋 (𝑓 ⊕ 𝑢) = 𝑤)
57	45, 53, 56	syl2anc 595	. . . . . . 7 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ ((ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋) ∧ ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤))) → ∃𝑓 ∈ 𝑋 (𝑓 ⊕ 𝑢) = 𝑤)
58	57	expr 461	. . . . . 6 ⊢ ((( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) ∧ (ℎ ∈ 𝑋 ∧ 𝑘 ∈ 𝑋)) → (((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤) → ∃𝑓 ∈ 𝑋 (𝑓 ⊕ 𝑢) = 𝑤))
59	58	rexlimdvva 3221	. . . . 5 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → (∃ℎ ∈ 𝑋 ∃𝑘 ∈ 𝑋 ((ℎ ⊕ 𝑢) = 𝑣 ∧ (𝑘 ⊕ 𝑣) = 𝑤) → ∃𝑓 ∈ 𝑋 (𝑓 ⊕ 𝑢) = 𝑤))
60	39, 59	biimtrrid 246	. . . 4 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → ((∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑣 ∧ ∃𝑘 ∈ 𝑋 (𝑘 ⊕ 𝑣) = 𝑤) → ∃𝑓 ∈ 𝑋 (𝑓 ⊕ 𝑢) = 𝑤))
61	37, 38, 60	mp2and 711	. . 3 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → ∃𝑓 ∈ 𝑋 (𝑓 ⊕ 𝑢) = 𝑤)
62	1	gaorb 19383	. . 3 ⊢ (𝑢 ∼ 𝑤 ↔ (𝑢 ∈ 𝑌 ∧ 𝑤 ∈ 𝑌 ∧ ∃𝑓 ∈ 𝑋 (𝑓 ⊕ 𝑢) = 𝑤))
63	32, 36, 61, 62	syl3anbrc 1361	. 2 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ (𝑢 ∼ 𝑣 ∧ 𝑣 ∼ 𝑤)) → 𝑢 ∼ 𝑤)
64	18	adantr 485	. . . . . . . 8 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∈ 𝑌) → 𝐺 ∈ Grp)
65		eqid 2762	. . . . . . . . 9 ⊢ (0g‘𝐺) = (0g‘𝐺)
66	14, 65	grpidcl 19038	. . . . . . . 8 ⊢ (𝐺 ∈ Grp → (0g‘𝐺) ∈ 𝑋)
67	64, 66	syl 18	. . . . . . 7 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∈ 𝑌) → (0g‘𝐺) ∈ 𝑋)
68	65	gagrpid 19370	. . . . . . 7 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∈ 𝑌) → ((0g‘𝐺) ⊕ 𝑢) = 𝑢)
69		oveq1 7419	. . . . . . . . 9 ⊢ (ℎ = (0g‘𝐺) → (ℎ ⊕ 𝑢) = ((0g‘𝐺) ⊕ 𝑢))
70	69	eqeq1d 2764	. . . . . . . 8 ⊢ (ℎ = (0g‘𝐺) → ((ℎ ⊕ 𝑢) = 𝑢 ↔ ((0g‘𝐺) ⊕ 𝑢) = 𝑢))
71	70	rspcev 3580	. . . . . . 7 ⊢ (((0g‘𝐺) ∈ 𝑋 ∧ ((0g‘𝐺) ⊕ 𝑢) = 𝑢) → ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢)
72	67, 68, 71	syl2anc 595	. . . . . 6 ⊢ (( ⊕ ∈ (𝐺 GrpAct 𝑌) ∧ 𝑢 ∈ 𝑌) → ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢)
73	72	ex 417	. . . . 5 ⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → (𝑢 ∈ 𝑌 → ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢))
74	73	pm4.71rd 571	. . . 4 ⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → (𝑢 ∈ 𝑌 ↔ (∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢 ∧ 𝑢 ∈ 𝑌)))
75		df-3an 1104	. . . . 5 ⊢ ((𝑢 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢) ↔ ((𝑢 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌) ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢))
76		anidm 574	. . . . . 6 ⊢ ((𝑢 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌) ↔ 𝑢 ∈ 𝑌)
77	76	anbi2ci 636	. . . . 5 ⊢ (((𝑢 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌) ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢) ↔ (∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢 ∧ 𝑢 ∈ 𝑌))
78	75, 77	bitri 278	. . . 4 ⊢ ((𝑢 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢) ↔ (∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢 ∧ 𝑢 ∈ 𝑌))
79	74, 78	bitr4di 292	. . 3 ⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → (𝑢 ∈ 𝑌 ↔ (𝑢 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢)))
80	1	gaorb 19383	. . 3 ⊢ (𝑢 ∼ 𝑢 ↔ (𝑢 ∈ 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝑢) = 𝑢))
81	79, 80	bitr4di 292	. 2 ⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → (𝑢 ∈ 𝑌 ↔ 𝑢 ∼ 𝑢))
82	3, 31, 63, 81	iserd 8719	1 ⊢ ( ⊕ ∈ (𝐺 GrpAct 𝑌) → ∼ Er 𝑌)

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 400   ∧ w3a 1102   = wceq 1569   ∈ wcel 2142  ∃wrex 3088   ⊆ wss 3904  {cpr 4590   class class class wbr 5108  {copab 5172  Rel wrel 5665  ‘cfv 6536  (class class class)co 7412   Er wer 8689  Basecbs 17275  +_gcplusg 17316  0_gc0g 17498  Grpcgrp 19006  inv_gcminusg 19007   GrpAct cga 19365

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-8 2144  ax-9 2152  ax-10 2175  ax-11 2191  ax-12 2212  ax-ext 2734  ax-sep 5256  ax-nul 5268  ax-pow 5335  ax-pr 5403  ax-un 7734

This proof depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1104  df-tru 1572  df-fal 1582  df-ex 1809  df-nf 1813  df-sb 2096  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rmo 3368  df-reu 3369  df-rab 3416  df-v 3456  df-sbc 3744  df-csb 3853  df-dif 3907  df-un 3909  df-in 3911  df-ss 3921  df-nul 4286  df-if 4487  df-pw 4563  df-sn 4589  df-pr 4591  df-op 4595  df-uni 4872  df-br 5109  df-opab 5173  df-mpt 5192  df-id 5555  df-xp 5666  df-rel 5667  df-cnv 5668  df-co 5669  df-dm 5670  df-rn 5671  df-res 5672  df-ima 5673  df-iota 6492  df-fun 6538  df-fn 6539  df-f 6540  df-fv 6544  df-riota 7369  df-ov 7415  df-oprab 7416  df-mpo 7417  df-er 8692  df-map 8824  df-0g 17500  df-mgm 18704  df-sgrp 18783  df-mnd 18799  df-grp 19009  df-minusg 19010  df-ga 19366

This theorem is used by:  sylow1lem3  19676  sylow1lem5  19678  sylow2alem1  19693  sylow2alem2  19694  sylow2a  19695  sylow3lem3  19705