Theorem fneval 32943

Description: Two covers are finer than each other iff they are both bases for the same topology. (Contributed by Mario Carneiro, 11-Sep-2015.)

Hypothesis

Ref	Expression
fneval.1	⊢ ∼ = (Fne ∩ ◡Fne)

Assertion

Ref	Expression
fneval	⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (𝐴 ∼ 𝐵 ↔ (topGen‘𝐴) = (topGen‘𝐵)))

Proof of Theorem fneval

Step	Hyp	Ref	Expression
1		fneval.1	. . . 4 ⊢ ∼ = (Fne ∩ ◡Fne)
2	1	breqi 4894	. . 3 ⊢ (𝐴 ∼ 𝐵 ↔ 𝐴(Fne ∩ ◡Fne)𝐵)
3		brin 4940	. . . 4 ⊢ (𝐴(Fne ∩ ◡Fne)𝐵 ↔ (𝐴Fne𝐵 ∧ 𝐴◡Fne𝐵))
4		fnerel 32929	. . . . . 6 ⊢ Rel Fne
5	4	relbrcnv 5762	. . . . 5 ⊢ (𝐴◡Fne𝐵 ↔ 𝐵Fne𝐴)
6	5	anbi2i 616	. . . 4 ⊢ ((𝐴Fne𝐵 ∧ 𝐴◡Fne𝐵) ↔ (𝐴Fne𝐵 ∧ 𝐵Fne𝐴))
7	3, 6	bitri 267	. . 3 ⊢ (𝐴(Fne ∩ ◡Fne)𝐵 ↔ (𝐴Fne𝐵 ∧ 𝐵Fne𝐴))
8	2, 7	bitri 267	. 2 ⊢ (𝐴 ∼ 𝐵 ↔ (𝐴Fne𝐵 ∧ 𝐵Fne𝐴))
9		eqid 2778	. . . . . 6 ⊢ ∪ 𝐴 = ∪ 𝐴
10		eqid 2778	. . . . . 6 ⊢ ∪ 𝐵 = ∪ 𝐵
11	9, 10	isfne4b 32932	. . . . 5 ⊢ (𝐵 ∈ 𝑊 → (𝐴Fne𝐵 ↔ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) ⊆ (topGen‘𝐵))))
12	10, 9	isfne4b 32932	. . . . . 6 ⊢ (𝐴 ∈ 𝑉 → (𝐵Fne𝐴 ↔ (∪ 𝐵 = ∪ 𝐴 ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴))))
13		eqcom 2785	. . . . . . 7 ⊢ (∪ 𝐵 = ∪ 𝐴 ↔ ∪ 𝐴 = ∪ 𝐵)
14	13	anbi1i 617	. . . . . 6 ⊢ ((∪ 𝐵 = ∪ 𝐴 ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴)) ↔ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴)))
15	12, 14	syl6bb 279	. . . . 5 ⊢ (𝐴 ∈ 𝑉 → (𝐵Fne𝐴 ↔ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴))))
16	11, 15	bi2anan9r 630	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((𝐴Fne𝐵 ∧ 𝐵Fne𝐴) ↔ ((∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) ⊆ (topGen‘𝐵)) ∧ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴)))))
17		eqss 3836	. . . . . 6 ⊢ ((topGen‘𝐴) = (topGen‘𝐵) ↔ ((topGen‘𝐴) ⊆ (topGen‘𝐵) ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴)))
18	17	anbi2i 616	. . . . 5 ⊢ ((∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) = (topGen‘𝐵)) ↔ (∪ 𝐴 = ∪ 𝐵 ∧ ((topGen‘𝐴) ⊆ (topGen‘𝐵) ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴))))
19		anandi 666	. . . . 5 ⊢ ((∪ 𝐴 = ∪ 𝐵 ∧ ((topGen‘𝐴) ⊆ (topGen‘𝐵) ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴))) ↔ ((∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) ⊆ (topGen‘𝐵)) ∧ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴))))
20	18, 19	bitri 267	. . . 4 ⊢ ((∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) = (topGen‘𝐵)) ↔ ((∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) ⊆ (topGen‘𝐵)) ∧ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐵) ⊆ (topGen‘𝐴))))
21	16, 20	syl6bbr 281	. . 3 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((𝐴Fne𝐵 ∧ 𝐵Fne𝐴) ↔ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) = (topGen‘𝐵))))
22		unieq 4681	. . . . 5 ⊢ ((topGen‘𝐴) = (topGen‘𝐵) → ∪ (topGen‘𝐴) = ∪ (topGen‘𝐵))
23		unitg 21190	. . . . . 6 ⊢ (𝐴 ∈ 𝑉 → ∪ (topGen‘𝐴) = ∪ 𝐴)
24		unitg 21190	. . . . . 6 ⊢ (𝐵 ∈ 𝑊 → ∪ (topGen‘𝐵) = ∪ 𝐵)
25	23, 24	eqeqan12d 2794	. . . . 5 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∪ (topGen‘𝐴) = ∪ (topGen‘𝐵) ↔ ∪ 𝐴 = ∪ 𝐵))
26	22, 25	syl5ib 236	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((topGen‘𝐴) = (topGen‘𝐵) → ∪ 𝐴 = ∪ 𝐵))
27	26	pm4.71rd 558	. . 3 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((topGen‘𝐴) = (topGen‘𝐵) ↔ (∪ 𝐴 = ∪ 𝐵 ∧ (topGen‘𝐴) = (topGen‘𝐵))))
28	21, 27	bitr4d 274	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((𝐴Fne𝐵 ∧ 𝐵Fne𝐴) ↔ (topGen‘𝐴) = (topGen‘𝐵)))
29	8, 28	syl5bb 275	1 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (𝐴 ∼ 𝐵 ↔ (topGen‘𝐴) = (topGen‘𝐵)))

Syntax hints:   → wi 4   ↔ wb 198   ∧ wa 386   = wceq 1601   ∈ wcel 2107   ∩ cin 3791   ⊆ wss 3792  ∪ cuni 4673   class class class wbr 4888  ^◡ccnv 5356  ‘cfv 6137  topGenctg 16495  Fnecfne 32927

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1839  ax-4 1853  ax-5 1953  ax-6 2021  ax-7 2055  ax-8 2109  ax-9 2116  ax-10 2135  ax-11 2150  ax-12 2163  ax-13 2334  ax-ext 2754  ax-sep 5019  ax-nul 5027  ax-pow 5079  ax-pr 5140  ax-un 7228

This theorem depends on definitions:  df-bi 199  df-an 387  df-or 837  df-3an 1073  df-tru 1605  df-ex 1824  df-nf 1828  df-sb 2012  df-mo 2551  df-eu 2587  df-clab 2764  df-cleq 2770  df-clel 2774  df-nfc 2921  df-ral 3095  df-rex 3096  df-rab 3099  df-v 3400  df-sbc 3653  df-dif 3795  df-un 3797  df-in 3799  df-ss 3806  df-nul 4142  df-if 4308  df-pw 4381  df-sn 4399  df-pr 4401  df-op 4405  df-uni 4674  df-iun 4757  df-br 4889  df-opab 4951  df-mpt 4968  df-id 5263  df-xp 5363  df-rel 5364  df-cnv 5365  df-co 5366  df-dm 5367  df-iota 6101  df-fun 6139  df-fv 6145  df-topgen 16501  df-fne 32928

This theorem is referenced by:  fneer  32944  topfneec  32946  topfneec2  32947