Metamath Proof Explorer


Theorem kelac2

Description: Kelley's choice, most common form: compactness of a product of knob topologies recovers choice. (Contributed by Stefan O'Rear, 22-Feb-2015)

Ref Expression
Hypotheses kelac2.s ⊢ φ ∧ x ∈ I → S ∈ V
kelac2.z ⊢ φ ∧ x ∈ I → S ≠ ∅
kelac2.k ⊢ φ → ∏ 𝑡 ⁡ x ∈ I ⟼ topGen ⁡ S 𝒫 ⋃ S ∈ Comp
Assertion kelac2 ⊢ φ → ⨉ x ∈ I S ≠ ∅

Proof

Step Hyp Ref Expression
1 kelac2.s ⊢ φ ∧ x ∈ I → S ∈ V
2 kelac2.z ⊢ φ ∧ x ∈ I → S ≠ ∅
3 kelac2.k ⊢ φ → ∏ 𝑡 ⁡ x ∈ I ⟼ topGen ⁡ S 𝒫 ⋃ S ∈ Comp
4 kelac2lem ⊢ S ∈ V → topGen ⁡ S 𝒫 ⋃ S ∈ Comp
5 cmptop ⊢ topGen ⁡ S 𝒫 ⋃ S ∈ Comp → topGen ⁡ S 𝒫 ⋃ S ∈ Top
6 1 4 5 3syl ⊢ φ ∧ x ∈ I → topGen ⁡ S 𝒫 ⋃ S ∈ Top
7 uncom ⊢ S ∪ 𝒫 ⋃ S = 𝒫 ⋃ S ∪ S
8 7 difeq1i ⊢ S ∪ 𝒫 ⋃ S ∖ S = 𝒫 ⋃ S ∪ S ∖ S
9 difun2 ⊢ 𝒫 ⋃ S ∪ S ∖ S = 𝒫 ⋃ S ∖ S
10 8 9 eqtri ⊢ S ∪ 𝒫 ⋃ S ∖ S = 𝒫 ⋃ S ∖ S
11 snex ⊢ 𝒫 ⋃ S ∈ V
12 uniprg ⊢ S ∈ V ∧ 𝒫 ⋃ S ∈ V → ⋃ S 𝒫 ⋃ S = S ∪ 𝒫 ⋃ S
13 1 11 12 sylancl ⊢ φ ∧ x ∈ I → ⋃ S 𝒫 ⋃ S = S ∪ 𝒫 ⋃ S
14 13 difeq1d ⊢ φ ∧ x ∈ I → ⋃ S 𝒫 ⋃ S ∖ S = S ∪ 𝒫 ⋃ S ∖ S
15 incom ⊢ 𝒫 ⋃ S ∩ S = S ∩ 𝒫 ⋃ S
16 pwuninel ⊢ ¬ 𝒫 ⋃ S ∈ S
17 16 a1i ⊢ φ ∧ x ∈ I → ¬ 𝒫 ⋃ S ∈ S
18 disjsn ⊢ S ∩ 𝒫 ⋃ S = ∅ ↔ ¬ 𝒫 ⋃ S ∈ S
19 17 18 sylibr ⊢ φ ∧ x ∈ I → S ∩ 𝒫 ⋃ S = ∅
20 15 19 eqtrid ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S ∩ S = ∅
21 disj3 ⊢ 𝒫 ⋃ S ∩ S = ∅ ↔ 𝒫 ⋃ S = 𝒫 ⋃ S ∖ S
22 20 21 sylib ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S = 𝒫 ⋃ S ∖ S
23 10 14 22 3eqtr4a ⊢ φ ∧ x ∈ I → ⋃ S 𝒫 ⋃ S ∖ S = 𝒫 ⋃ S
24 prex ⊢ S 𝒫 ⋃ S ∈ V
25 bastg ⊢ S 𝒫 ⋃ S ∈ V → S 𝒫 ⋃ S ⊆ topGen ⁡ S 𝒫 ⋃ S
26 24 25 mp1i ⊢ φ ∧ x ∈ I → S 𝒫 ⋃ S ⊆ topGen ⁡ S 𝒫 ⋃ S
27 11 prid2 ⊢ 𝒫 ⋃ S ∈ S 𝒫 ⋃ S
28 27 a1i ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S ∈ S 𝒫 ⋃ S
29 26 28 sseldd ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S ∈ topGen ⁡ S 𝒫 ⋃ S
30 23 29 eqeltrd ⊢ φ ∧ x ∈ I → ⋃ S 𝒫 ⋃ S ∖ S ∈ topGen ⁡ S 𝒫 ⋃ S
31 prid1g ⊢ S ∈ V → S ∈ S 𝒫 ⋃ S
32 elssuni ⊢ S ∈ S 𝒫 ⋃ S → S ⊆ ⋃ S 𝒫 ⋃ S
33 1 31 32 3syl ⊢ φ ∧ x ∈ I → S ⊆ ⋃ S 𝒫 ⋃ S
34 unitg ⊢ S 𝒫 ⋃ S ∈ V → ⋃ topGen ⁡ S 𝒫 ⋃ S = ⋃ S 𝒫 ⋃ S
35 24 34 ax-mp ⊢ ⋃ topGen ⁡ S 𝒫 ⋃ S = ⋃ S 𝒫 ⋃ S
36 35 eqcomi ⊢ ⋃ S 𝒫 ⋃ S = ⋃ topGen ⁡ S 𝒫 ⋃ S
37 36 iscld2 ⊢ topGen ⁡ S 𝒫 ⋃ S ∈ Top ∧ S ⊆ ⋃ S 𝒫 ⋃ S → S ∈ Clsd ⁡ topGen ⁡ S 𝒫 ⋃ S ↔ ⋃ S 𝒫 ⋃ S ∖ S ∈ topGen ⁡ S 𝒫 ⋃ S
38 6 33 37 syl2anc ⊢ φ ∧ x ∈ I → S ∈ Clsd ⁡ topGen ⁡ S 𝒫 ⋃ S ↔ ⋃ S 𝒫 ⋃ S ∖ S ∈ topGen ⁡ S 𝒫 ⋃ S
39 30 38 mpbird ⊢ φ ∧ x ∈ I → S ∈ Clsd ⁡ topGen ⁡ S 𝒫 ⋃ S
40 f1oi ⊢ I ↾ S : S ⟶ 1-1 onto S
41 40 a1i ⊢ φ ∧ x ∈ I → I ↾ S : S ⟶ 1-1 onto S
42 elssuni ⊢ 𝒫 ⋃ S ∈ S 𝒫 ⋃ S → 𝒫 ⋃ S ⊆ ⋃ S 𝒫 ⋃ S
43 27 42 mp1i ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S ⊆ ⋃ S 𝒫 ⋃ S
44 uniexg ⊢ S ∈ V → ⋃ S ∈ V
45 pwexg ⊢ ⋃ S ∈ V → 𝒫 ⋃ S ∈ V
46 snidg ⊢ 𝒫 ⋃ S ∈ V → 𝒫 ⋃ S ∈ 𝒫 ⋃ S
47 1 44 45 46 4syl ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S ∈ 𝒫 ⋃ S
48 43 47 sseldd ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S ∈ ⋃ S 𝒫 ⋃ S
49 48 35 eleqtrrdi ⊢ φ ∧ x ∈ I → 𝒫 ⋃ S ∈ ⋃ topGen ⁡ S 𝒫 ⋃ S
50 2 6 39 41 49 3 kelac1 ⊢ φ → ⨉ x ∈ I S ≠ ∅