Metamath Proof Explorer


Theorem fclsfnflim

Description: A filter clusters at a point iff a finer filter converges to it. (Contributed by Jeff Hankins, 12-Nov-2009) (Revised by Mario Carneiro, 26-Aug-2015)

Ref Expression
Assertion fclsfnflim ⊢ F ∈ Fil ⁡ X → A ∈ J fClus F ↔ ∃ g ∈ Fil ⁡ X F ⊆ g ∧ A ∈ J fLim g

Proof

Step Hyp Ref Expression
1 filsspw ⊢ F ∈ Fil ⁡ X → F ⊆ 𝒫 X
2 1 adantr ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → F ⊆ 𝒫 X
3 fclstop ⊢ A ∈ J fClus F → J ∈ Top
4 3 adantl ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → J ∈ Top
5 eqid ⊢ ⋃ J = ⋃ J
6 5 neisspw ⊢ J ∈ Top → nei ⁡ J ⁡ A ⊆ 𝒫 ⋃ J
7 4 6 syl ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → nei ⁡ J ⁡ A ⊆ 𝒫 ⋃ J
8 filunibas ⊢ F ∈ Fil ⁡ X → ⋃ F = X
9 5 fclsfil ⊢ A ∈ J fClus F → F ∈ Fil ⁡ ⋃ J
10 filunibas ⊢ F ∈ Fil ⁡ ⋃ J → ⋃ F = ⋃ J
11 9 10 syl ⊢ A ∈ J fClus F → ⋃ F = ⋃ J
12 8 11 sylan9req ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → X = ⋃ J
13 12 pweqd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → 𝒫 X = 𝒫 ⋃ J
14 7 13 sseqtrrd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → nei ⁡ J ⁡ A ⊆ 𝒫 X
15 2 14 unssd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → F ∪ nei ⁡ J ⁡ A ⊆ 𝒫 X
16 ssun1 ⊢ F ⊆ F ∪ nei ⁡ J ⁡ A
17 filn0 ⊢ F ∈ Fil ⁡ X → F ≠ ∅
18 ssn0 ⊢ F ⊆ F ∪ nei ⁡ J ⁡ A ∧ F ≠ ∅ → F ∪ nei ⁡ J ⁡ A ≠ ∅
19 16 17 18 sylancr ⊢ F ∈ Fil ⁡ X → F ∪ nei ⁡ J ⁡ A ≠ ∅
20 19 adantr ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → F ∪ nei ⁡ J ⁡ A ≠ ∅
21 incom ⊢ y ∩ x = x ∩ y
22 fclsneii ⊢ A ∈ J fClus F ∧ y ∈ nei ⁡ J ⁡ A ∧ x ∈ F → y ∩ x ≠ ∅
23 21 22 eqnetrrid ⊢ A ∈ J fClus F ∧ y ∈ nei ⁡ J ⁡ A ∧ x ∈ F → x ∩ y ≠ ∅
24 23 3com23 ⊢ A ∈ J fClus F ∧ x ∈ F ∧ y ∈ nei ⁡ J ⁡ A → x ∩ y ≠ ∅
25 24 3expb ⊢ A ∈ J fClus F ∧ x ∈ F ∧ y ∈ nei ⁡ J ⁡ A → x ∩ y ≠ ∅
26 25 adantll ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F ∧ x ∈ F ∧ y ∈ nei ⁡ J ⁡ A → x ∩ y ≠ ∅
27 26 ralrimivva ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → ∀ x ∈ F ∀ y ∈ nei ⁡ J ⁡ A x ∩ y ≠ ∅
28 filfbas ⊢ F ∈ Fil ⁡ X → F ∈ fBas ⁡ X
29 28 adantr ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → F ∈ fBas ⁡ X
30 istopon ⊢ J ∈ TopOn ⁡ X ↔ J ∈ Top ∧ X = ⋃ J
31 4 12 30 sylanbrc ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → J ∈ TopOn ⁡ X
32 5 fclselbas ⊢ A ∈ J fClus F → A ∈ ⋃ J
33 32 adantl ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → A ∈ ⋃ J
34 33 12 eleqtrrd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → A ∈ X
35 34 snssd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → A ⊆ X
36 snnzg ⊢ A ∈ J fClus F → A ≠ ∅
37 36 adantl ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → A ≠ ∅
38 neifil ⊢ J ∈ TopOn ⁡ X ∧ A ⊆ X ∧ A ≠ ∅ → nei ⁡ J ⁡ A ∈ Fil ⁡ X
39 31 35 37 38 syl3anc ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → nei ⁡ J ⁡ A ∈ Fil ⁡ X
40 filfbas ⊢ nei ⁡ J ⁡ A ∈ Fil ⁡ X → nei ⁡ J ⁡ A ∈ fBas ⁡ X
41 39 40 syl ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → nei ⁡ J ⁡ A ∈ fBas ⁡ X
42 fbunfip ⊢ F ∈ fBas ⁡ X ∧ nei ⁡ J ⁡ A ∈ fBas ⁡ X → ¬ ∅ ∈ fi ⁡ F ∪ nei ⁡ J ⁡ A ↔ ∀ x ∈ F ∀ y ∈ nei ⁡ J ⁡ A x ∩ y ≠ ∅
43 29 41 42 syl2anc ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → ¬ ∅ ∈ fi ⁡ F ∪ nei ⁡ J ⁡ A ↔ ∀ x ∈ F ∀ y ∈ nei ⁡ J ⁡ A x ∩ y ≠ ∅
44 27 43 mpbird ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → ¬ ∅ ∈ fi ⁡ F ∪ nei ⁡ J ⁡ A
45 filtop ⊢ F ∈ Fil ⁡ X → X ∈ F
46 fsubbas ⊢ X ∈ F → fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ fBas ⁡ X ↔ F ∪ nei ⁡ J ⁡ A ⊆ 𝒫 X ∧ F ∪ nei ⁡ J ⁡ A ≠ ∅ ∧ ¬ ∅ ∈ fi ⁡ F ∪ nei ⁡ J ⁡ A
47 45 46 syl ⊢ F ∈ Fil ⁡ X → fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ fBas ⁡ X ↔ F ∪ nei ⁡ J ⁡ A ⊆ 𝒫 X ∧ F ∪ nei ⁡ J ⁡ A ≠ ∅ ∧ ¬ ∅ ∈ fi ⁡ F ∪ nei ⁡ J ⁡ A
48 47 adantr ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ fBas ⁡ X ↔ F ∪ nei ⁡ J ⁡ A ⊆ 𝒫 X ∧ F ∪ nei ⁡ J ⁡ A ≠ ∅ ∧ ¬ ∅ ∈ fi ⁡ F ∪ nei ⁡ J ⁡ A
49 15 20 44 48 mpbir3and ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ fBas ⁡ X
50 fgcl ⊢ fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ fBas ⁡ X → X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ Fil ⁡ X
51 49 50 syl ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ Fil ⁡ X
52 fvex ⊢ nei ⁡ J ⁡ A ∈ V
53 unexg ⊢ F ∈ Fil ⁡ X ∧ nei ⁡ J ⁡ A ∈ V → F ∪ nei ⁡ J ⁡ A ∈ V
54 52 53 mpan2 ⊢ F ∈ Fil ⁡ X → F ∪ nei ⁡ J ⁡ A ∈ V
55 ssfii ⊢ F ∪ nei ⁡ J ⁡ A ∈ V → F ∪ nei ⁡ J ⁡ A ⊆ fi ⁡ F ∪ nei ⁡ J ⁡ A
56 54 55 syl ⊢ F ∈ Fil ⁡ X → F ∪ nei ⁡ J ⁡ A ⊆ fi ⁡ F ∪ nei ⁡ J ⁡ A
57 56 adantr ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → F ∪ nei ⁡ J ⁡ A ⊆ fi ⁡ F ∪ nei ⁡ J ⁡ A
58 57 unssad ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → F ⊆ fi ⁡ F ∪ nei ⁡ J ⁡ A
59 ssfg ⊢ fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ fBas ⁡ X → fi ⁡ F ∪ nei ⁡ J ⁡ A ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
60 49 59 syl ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → fi ⁡ F ∪ nei ⁡ J ⁡ A ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
61 58 60 sstrd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → F ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
62 57 unssbd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → nei ⁡ J ⁡ A ⊆ fi ⁡ F ∪ nei ⁡ J ⁡ A
63 62 60 sstrd ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → nei ⁡ J ⁡ A ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
64 elflim ⊢ J ∈ TopOn ⁡ X ∧ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ Fil ⁡ X → A ∈ J fLim X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ↔ A ∈ X ∧ nei ⁡ J ⁡ A ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
65 31 51 64 syl2anc ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → A ∈ J fLim X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ↔ A ∈ X ∧ nei ⁡ J ⁡ A ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
66 34 63 65 mpbir2and ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → A ∈ J fLim X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
67 sseq2 ⊢ g = X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A → F ⊆ g ↔ F ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
68 oveq2 ⊢ g = X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A → J fLim g = J fLim X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
69 68 eleq2d ⊢ g = X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A → A ∈ J fLim g ↔ A ∈ J fLim X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
70 67 69 anbi12d ⊢ g = X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A → F ⊆ g ∧ A ∈ J fLim g ↔ F ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ∧ A ∈ J fLim X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A
71 70 rspcev ⊢ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ∈ Fil ⁡ X ∧ F ⊆ X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A ∧ A ∈ J fLim X filGen fi ⁡ F ∪ nei ⁡ J ⁡ A → ∃ g ∈ Fil ⁡ X F ⊆ g ∧ A ∈ J fLim g
72 51 61 66 71 syl12anc ⊢ F ∈ Fil ⁡ X ∧ A ∈ J fClus F → ∃ g ∈ Fil ⁡ X F ⊆ g ∧ A ∈ J fLim g
73 72 ex ⊢ F ∈ Fil ⁡ X → A ∈ J fClus F → ∃ g ∈ Fil ⁡ X F ⊆ g ∧ A ∈ J fLim g
74 simprl ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → g ∈ Fil ⁡ X
75 simprrr ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → A ∈ J fLim g
76 flimtopon ⊢ A ∈ J fLim g → J ∈ TopOn ⁡ X ↔ g ∈ Fil ⁡ X
77 75 76 syl ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → J ∈ TopOn ⁡ X ↔ g ∈ Fil ⁡ X
78 74 77 mpbird ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → J ∈ TopOn ⁡ X
79 simpl ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → F ∈ Fil ⁡ X
80 simprrl ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → F ⊆ g
81 fclsss2 ⊢ J ∈ TopOn ⁡ X ∧ F ∈ Fil ⁡ X ∧ F ⊆ g → J fClus g ⊆ J fClus F
82 78 79 80 81 syl3anc ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → J fClus g ⊆ J fClus F
83 flimfcls ⊢ J fLim g ⊆ J fClus g
84 83 75 sselid ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → A ∈ J fClus g
85 82 84 sseldd ⊢ F ∈ Fil ⁡ X ∧ g ∈ Fil ⁡ X ∧ F ⊆ g ∧ A ∈ J fLim g → A ∈ J fClus F
86 85 rexlimdvaa ⊢ F ∈ Fil ⁡ X → ∃ g ∈ Fil ⁡ X F ⊆ g ∧ A ∈ J fLim g → A ∈ J fClus F
87 73 86 impbid ⊢ F ∈ Fil ⁡ X → A ∈ J fClus F ↔ ∃ g ∈ Fil ⁡ X F ⊆ g ∧ A ∈ J fLim g