Theorem gaorb 19521

Description: The orbit equivalence relation puts two points in the group action in the same equivalence class iff there is a group element that takes one element to the other. (Contributed by Mario Carneiro, 14-Jan-2015.)

Hypothesis

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

Assertion

Ref	Expression
gaorb	⊢ (𝐴 ∼ 𝐵 ↔ (𝐴 ∈ 𝑌 ∧ 𝐵 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝐴) = 𝐵))

Distinct variable groups:   𝑔,ℎ,𝑥,𝑦,𝐴   𝐵,𝑔,ℎ,𝑥,𝑦   ∼ ,ℎ   ⊕ ,𝑔,ℎ,𝑥,𝑦   𝑔,𝑋,ℎ,𝑥,𝑦   ℎ,𝑌,𝑥,𝑦

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

Proof of Theorem gaorb

Step	Hyp	Ref	Expression
1		oveq2 7428	. . . . . 6 ⊢ (𝑥 = 𝐴 → (𝑔 ⊕ 𝑥) = (𝑔 ⊕ 𝐴))
2		eqeq12 2778	. . . . . 6 ⊢ (((𝑔 ⊕ 𝑥) = (𝑔 ⊕ 𝐴) ∧ 𝑦 = 𝐵) → ((𝑔 ⊕ 𝑥) = 𝑦 ↔ (𝑔 ⊕ 𝐴) = 𝐵))
3	1, 2	sylan 592	. . . . 5 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → ((𝑔 ⊕ 𝑥) = 𝑦 ↔ (𝑔 ⊕ 𝐴) = 𝐵))
4	3	rexbidv 3187	. . . 4 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦 ↔ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝐴) = 𝐵))
5		oveq1 7427	. . . . . 6 ⊢ (𝑔 = ℎ → (𝑔 ⊕ 𝐴) = (ℎ ⊕ 𝐴))
6	5	eqeq1d 2763	. . . . 5 ⊢ (𝑔 = ℎ → ((𝑔 ⊕ 𝐴) = 𝐵 ↔ (ℎ ⊕ 𝐴) = 𝐵))
7	6	cbvrexvw 3242	. . . 4 ⊢ (∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝐴) = 𝐵 ↔ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝐴) = 𝐵)
8	4, 7	bitrdi 290	. . 3 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦 ↔ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝐴) = 𝐵))
9		gaorb.1	. . . 4 ⊢ ∼ = {⟨𝑥, 𝑦⟩ ∣ ({𝑥, 𝑦} ⊆ 𝑌 ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦)}
10		vex 3455	. . . . . . 7 ⊢ 𝑥 ∈ V
11		vex 3455	. . . . . . 7 ⊢ 𝑦 ∈ V
12	10, 11	prss 4781	. . . . . 6 ⊢ ((𝑥 ∈ 𝑌 ∧ 𝑦 ∈ 𝑌) ↔ {𝑥, 𝑦} ⊆ 𝑌)
13	12	anbi1i 636	. . . . 5 ⊢ (((𝑥 ∈ 𝑌 ∧ 𝑦 ∈ 𝑌) ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦) ↔ ({𝑥, 𝑦} ⊆ 𝑌 ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦))
14	13	opabbii 5172	. . . 4 ⊢ {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝑌 ∧ 𝑦 ∈ 𝑌) ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦)} = {⟨𝑥, 𝑦⟩ ∣ ({𝑥, 𝑦} ⊆ 𝑌 ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦)}
15	9, 14	eqtr4i 2787	. . 3 ⊢ ∼ = {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ 𝑌 ∧ 𝑦 ∈ 𝑌) ∧ ∃𝑔 ∈ 𝑋 (𝑔 ⊕ 𝑥) = 𝑦)}
16	8, 15	brab2a 5744	. 2 ⊢ (𝐴 ∼ 𝐵 ↔ ((𝐴 ∈ 𝑌 ∧ 𝐵 ∈ 𝑌) ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝐴) = 𝐵))
17		df-3an 1105	. 2 ⊢ ((𝐴 ∈ 𝑌 ∧ 𝐵 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝐴) = 𝐵) ↔ ((𝐴 ∈ 𝑌 ∧ 𝐵 ∈ 𝑌) ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝐴) = 𝐵))
18	16, 17	bitr4i 281	1 ⊢ (𝐴 ∼ 𝐵 ↔ (𝐴 ∈ 𝑌 ∧ 𝐵 ∈ 𝑌 ∧ ∃ℎ ∈ 𝑋 (ℎ ⊕ 𝐴) = 𝐵))

This proof depends on syntax axioms:   ↔ wb 209   ∧ wa 401   ∧ w3a 1103   = wceq 1570   ∈ wcel 2145  ∃wrex 3087   ⊆ wss 3899  {cpr 4586   class class class wbr 5103  {copab 5167  (class class class)co 7420

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-ext 2733  ax-sep 5249  ax-pr 5391

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-sb 2100  df-clab 2740  df-cleq 2753  df-clel 2836  df-ral 3078  df-rex 3088  df-rab 3414  df-v 3453  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-opab 5168  df-xp 5657  df-iota 6494  df-fv 6546  df-ov 7423

This theorem is used by:  gaorber  19522  orbsta  19527  sylow2alem1  19831  sylow2alem2  19832  sylow3lem3  19843  lsmsnorb  33946