Metamath Proof Explorer


Theorem istopclsd

Description: A closure function which satisfies sscls , clsidm , cls0 , and clsun defines a (unique) topology which it is the closure function on. (Contributed by Stefan O'Rear, 1-Feb-2015)

Ref Expression
Hypotheses istopclsd.b ( 𝜑𝐵𝑉 )
istopclsd.f ( 𝜑𝐹 : 𝒫 𝐵 ⟶ 𝒫 𝐵 )
istopclsd.e ( ( 𝜑𝑥𝐵 ) → 𝑥 ⊆ ( 𝐹𝑥 ) )
istopclsd.i ( ( 𝜑𝑥𝐵 ) → ( 𝐹 ‘ ( 𝐹𝑥 ) ) = ( 𝐹𝑥 ) )
istopclsd.z ( 𝜑 → ( 𝐹 ‘ ∅ ) = ∅ )
istopclsd.u ( ( 𝜑𝑥𝐵𝑦𝐵 ) → ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( ( 𝐹𝑥 ) ∪ ( 𝐹𝑦 ) ) )
istopclsd.j 𝐽 = { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐹 ‘ ( 𝐵𝑧 ) ) = ( 𝐵𝑧 ) }
Assertion istopclsd ( 𝜑 → ( 𝐽 ∈ ( TopOn ‘ 𝐵 ) ∧ ( cls ‘ 𝐽 ) = 𝐹 ) )

Proof

Step Hyp Ref Expression
1 istopclsd.b ( 𝜑𝐵𝑉 )
2 istopclsd.f ( 𝜑𝐹 : 𝒫 𝐵 ⟶ 𝒫 𝐵 )
3 istopclsd.e ( ( 𝜑𝑥𝐵 ) → 𝑥 ⊆ ( 𝐹𝑥 ) )
4 istopclsd.i ( ( 𝜑𝑥𝐵 ) → ( 𝐹 ‘ ( 𝐹𝑥 ) ) = ( 𝐹𝑥 ) )
5 istopclsd.z ( 𝜑 → ( 𝐹 ‘ ∅ ) = ∅ )
6 istopclsd.u ( ( 𝜑𝑥𝐵𝑦𝐵 ) → ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( ( 𝐹𝑥 ) ∪ ( 𝐹𝑦 ) ) )
7 istopclsd.j 𝐽 = { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐹 ‘ ( 𝐵𝑧 ) ) = ( 𝐵𝑧 ) }
8 2 ffnd ( 𝜑𝐹 Fn 𝒫 𝐵 )
9 8 adantr ( ( 𝜑𝑧 ∈ 𝒫 𝐵 ) → 𝐹 Fn 𝒫 𝐵 )
10 difss ( 𝐵𝑧 ) ⊆ 𝐵
11 elpw2g ( 𝐵𝑉 → ( ( 𝐵𝑧 ) ∈ 𝒫 𝐵 ↔ ( 𝐵𝑧 ) ⊆ 𝐵 ) )
12 1 11 syl ( 𝜑 → ( ( 𝐵𝑧 ) ∈ 𝒫 𝐵 ↔ ( 𝐵𝑧 ) ⊆ 𝐵 ) )
13 10 12 mpbiri ( 𝜑 → ( 𝐵𝑧 ) ∈ 𝒫 𝐵 )
14 13 adantr ( ( 𝜑𝑧 ∈ 𝒫 𝐵 ) → ( 𝐵𝑧 ) ∈ 𝒫 𝐵 )
15 fnelfp ( ( 𝐹 Fn 𝒫 𝐵 ∧ ( 𝐵𝑧 ) ∈ 𝒫 𝐵 ) → ( ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹 ‘ ( 𝐵𝑧 ) ) = ( 𝐵𝑧 ) ) )
16 9 14 15 syl2anc ( ( 𝜑𝑧 ∈ 𝒫 𝐵 ) → ( ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹 ‘ ( 𝐵𝑧 ) ) = ( 𝐵𝑧 ) ) )
17 16 bicomd ( ( 𝜑𝑧 ∈ 𝒫 𝐵 ) → ( ( 𝐹 ‘ ( 𝐵𝑧 ) ) = ( 𝐵𝑧 ) ↔ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) ) )
18 17 rabbidva ( 𝜑 → { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐹 ‘ ( 𝐵𝑧 ) ) = ( 𝐵𝑧 ) } = { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } )
19 7 18 syl5eq ( 𝜑𝐽 = { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } )
20 simp1 ( ( 𝜑𝑥𝐵𝑦𝑥 ) → 𝜑 )
21 simp2 ( ( 𝜑𝑥𝐵𝑦𝑥 ) → 𝑥𝐵 )
22 simp3 ( ( 𝜑𝑥𝐵𝑦𝑥 ) → 𝑦𝑥 )
23 22 21 sstrd ( ( 𝜑𝑥𝐵𝑦𝑥 ) → 𝑦𝐵 )
24 20 21 23 6 syl3anc ( ( 𝜑𝑥𝐵𝑦𝑥 ) → ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( ( 𝐹𝑥 ) ∪ ( 𝐹𝑦 ) ) )
25 ssequn2 ( 𝑦𝑥 ↔ ( 𝑥𝑦 ) = 𝑥 )
26 25 biimpi ( 𝑦𝑥 → ( 𝑥𝑦 ) = 𝑥 )
27 26 3ad2ant3 ( ( 𝜑𝑥𝐵𝑦𝑥 ) → ( 𝑥𝑦 ) = 𝑥 )
28 27 fveq2d ( ( 𝜑𝑥𝐵𝑦𝑥 ) → ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( 𝐹𝑥 ) )
29 24 28 eqtr3d ( ( 𝜑𝑥𝐵𝑦𝑥 ) → ( ( 𝐹𝑥 ) ∪ ( 𝐹𝑦 ) ) = ( 𝐹𝑥 ) )
30 ssequn2 ( ( 𝐹𝑦 ) ⊆ ( 𝐹𝑥 ) ↔ ( ( 𝐹𝑥 ) ∪ ( 𝐹𝑦 ) ) = ( 𝐹𝑥 ) )
31 29 30 sylibr ( ( 𝜑𝑥𝐵𝑦𝑥 ) → ( 𝐹𝑦 ) ⊆ ( 𝐹𝑥 ) )
32 1 2 3 31 4 ismrcd1 ( 𝜑 → dom ( 𝐹 ∩ I ) ∈ ( Moore ‘ 𝐵 ) )
33 0elpw ∅ ∈ 𝒫 𝐵
34 fnelfp ( ( 𝐹 Fn 𝒫 𝐵 ∧ ∅ ∈ 𝒫 𝐵 ) → ( ∅ ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹 ‘ ∅ ) = ∅ ) )
35 8 33 34 sylancl ( 𝜑 → ( ∅ ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹 ‘ ∅ ) = ∅ ) )
36 5 35 mpbird ( 𝜑 → ∅ ∈ dom ( 𝐹 ∩ I ) )
37 simp1 ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝜑 )
38 inss1 ( 𝐹 ∩ I ) ⊆ 𝐹
39 dmss ( ( 𝐹 ∩ I ) ⊆ 𝐹 → dom ( 𝐹 ∩ I ) ⊆ dom 𝐹 )
40 38 39 ax-mp dom ( 𝐹 ∩ I ) ⊆ dom 𝐹
41 40 2 fssdm ( 𝜑 → dom ( 𝐹 ∩ I ) ⊆ 𝒫 𝐵 )
42 41 3ad2ant1 ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → dom ( 𝐹 ∩ I ) ⊆ 𝒫 𝐵 )
43 simp2 ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝑥 ∈ dom ( 𝐹 ∩ I ) )
44 42 43 sseldd ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝑥 ∈ 𝒫 𝐵 )
45 44 elpwid ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝑥𝐵 )
46 simp3 ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝑦 ∈ dom ( 𝐹 ∩ I ) )
47 42 46 sseldd ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝑦 ∈ 𝒫 𝐵 )
48 47 elpwid ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝑦𝐵 )
49 37 45 48 6 syl3anc ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( ( 𝐹𝑥 ) ∪ ( 𝐹𝑦 ) ) )
50 8 3ad2ant1 ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → 𝐹 Fn 𝒫 𝐵 )
51 fnelfp ( ( 𝐹 Fn 𝒫 𝐵𝑥 ∈ 𝒫 𝐵 ) → ( 𝑥 ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹𝑥 ) = 𝑥 ) )
52 50 44 51 syl2anc ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝑥 ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹𝑥 ) = 𝑥 ) )
53 43 52 mpbid ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝐹𝑥 ) = 𝑥 )
54 fnelfp ( ( 𝐹 Fn 𝒫 𝐵𝑦 ∈ 𝒫 𝐵 ) → ( 𝑦 ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹𝑦 ) = 𝑦 ) )
55 50 47 54 syl2anc ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝑦 ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹𝑦 ) = 𝑦 ) )
56 46 55 mpbid ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝐹𝑦 ) = 𝑦 )
57 53 56 uneq12d ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( ( 𝐹𝑥 ) ∪ ( 𝐹𝑦 ) ) = ( 𝑥𝑦 ) )
58 49 57 eqtrd ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( 𝑥𝑦 ) )
59 45 48 unssd ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝑥𝑦 ) ⊆ 𝐵 )
60 vex 𝑥 ∈ V
61 vex 𝑦 ∈ V
62 60 61 unex ( 𝑥𝑦 ) ∈ V
63 62 elpw ( ( 𝑥𝑦 ) ∈ 𝒫 𝐵 ↔ ( 𝑥𝑦 ) ⊆ 𝐵 )
64 59 63 sylibr ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝑥𝑦 ) ∈ 𝒫 𝐵 )
65 fnelfp ( ( 𝐹 Fn 𝒫 𝐵 ∧ ( 𝑥𝑦 ) ∈ 𝒫 𝐵 ) → ( ( 𝑥𝑦 ) ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( 𝑥𝑦 ) ) )
66 50 64 65 syl2anc ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( ( 𝑥𝑦 ) ∈ dom ( 𝐹 ∩ I ) ↔ ( 𝐹 ‘ ( 𝑥𝑦 ) ) = ( 𝑥𝑦 ) ) )
67 58 66 mpbird ( ( 𝜑𝑥 ∈ dom ( 𝐹 ∩ I ) ∧ 𝑦 ∈ dom ( 𝐹 ∩ I ) ) → ( 𝑥𝑦 ) ∈ dom ( 𝐹 ∩ I ) )
68 eqid { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } = { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) }
69 32 36 67 68 mretopd ( 𝜑 → ( { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } ∈ ( TopOn ‘ 𝐵 ) ∧ dom ( 𝐹 ∩ I ) = ( Clsd ‘ { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } ) ) )
70 69 simpld ( 𝜑 → { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } ∈ ( TopOn ‘ 𝐵 ) )
71 19 70 eqeltrd ( 𝜑𝐽 ∈ ( TopOn ‘ 𝐵 ) )
72 topontop ( 𝐽 ∈ ( TopOn ‘ 𝐵 ) → 𝐽 ∈ Top )
73 71 72 syl ( 𝜑𝐽 ∈ Top )
74 eqid ( mrCls ‘ ( Clsd ‘ 𝐽 ) ) = ( mrCls ‘ ( Clsd ‘ 𝐽 ) )
75 74 mrccls ( 𝐽 ∈ Top → ( cls ‘ 𝐽 ) = ( mrCls ‘ ( Clsd ‘ 𝐽 ) ) )
76 73 75 syl ( 𝜑 → ( cls ‘ 𝐽 ) = ( mrCls ‘ ( Clsd ‘ 𝐽 ) ) )
77 69 simprd ( 𝜑 → dom ( 𝐹 ∩ I ) = ( Clsd ‘ { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } ) )
78 19 fveq2d ( 𝜑 → ( Clsd ‘ 𝐽 ) = ( Clsd ‘ { 𝑧 ∈ 𝒫 𝐵 ∣ ( 𝐵𝑧 ) ∈ dom ( 𝐹 ∩ I ) } ) )
79 77 78 eqtr4d ( 𝜑 → dom ( 𝐹 ∩ I ) = ( Clsd ‘ 𝐽 ) )
80 79 fveq2d ( 𝜑 → ( mrCls ‘ dom ( 𝐹 ∩ I ) ) = ( mrCls ‘ ( Clsd ‘ 𝐽 ) ) )
81 76 80 eqtr4d ( 𝜑 → ( cls ‘ 𝐽 ) = ( mrCls ‘ dom ( 𝐹 ∩ I ) ) )
82 1 2 3 31 4 ismrcd2 ( 𝜑𝐹 = ( mrCls ‘ dom ( 𝐹 ∩ I ) ) )
83 81 82 eqtr4d ( 𝜑 → ( cls ‘ 𝐽 ) = 𝐹 )
84 71 83 jca ( 𝜑 → ( 𝐽 ∈ ( TopOn ‘ 𝐵 ) ∧ ( cls ‘ 𝐽 ) = 𝐹 ) )