Metamath Proof Explorer


Theorem cmpcref

Description: Equivalent definition of compact space in terms of open cover refinements. Compact spaces are topologies with finite open cover refinements. (Contributed by Thierry Arnoux, 7-Jan-2020)

Ref Expression
Assertion cmpcref Comp = CovHasRef Fin

Proof

Step Hyp Ref Expression
1 simplr ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) )
2 elin ( 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ↔ ( 𝑥 ∈ 𝒫 𝑦𝑥 ∈ Fin ) )
3 1 2 sylib ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → ( 𝑥 ∈ 𝒫 𝑦𝑥 ∈ Fin ) )
4 3 simpld ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥 ∈ 𝒫 𝑦 )
5 elpwi ( 𝑥 ∈ 𝒫 𝑦𝑥𝑦 )
6 4 5 syl ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥𝑦 )
7 elpwi ( 𝑦 ∈ 𝒫 𝑗𝑦𝑗 )
8 7 ad4antlr ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑦𝑗 )
9 6 8 sstrd ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥𝑗 )
10 velpw ( 𝑥 ∈ 𝒫 𝑗𝑥𝑗 )
11 9 10 sylibr ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥 ∈ 𝒫 𝑗 )
12 3 simprd ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥 ∈ Fin )
13 11 12 elind ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥 ∈ ( 𝒫 𝑗 ∩ Fin ) )
14 simpr ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑗 = 𝑥 )
15 simpllr ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑗 = 𝑦 )
16 14 15 eqtr3d ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥 = 𝑦 )
17 eqid 𝑥 = 𝑥
18 eqid 𝑦 = 𝑦
19 17 18 ssref ( ( 𝑥 ∈ 𝒫 𝑗𝑥𝑦 𝑥 = 𝑦 ) → 𝑥 Ref 𝑦 )
20 11 6 16 19 syl3anc ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → 𝑥 Ref 𝑦 )
21 breq1 ( 𝑧 = 𝑥 → ( 𝑧 Ref 𝑦𝑥 Ref 𝑦 ) )
22 21 rspcev ( ( 𝑥 ∈ ( 𝒫 𝑗 ∩ Fin ) ∧ 𝑥 Ref 𝑦 ) → ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 )
23 13 20 22 syl2anc ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) ) ∧ 𝑗 = 𝑥 ) → ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 )
24 23 r19.29an ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ) → ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 )
25 simplr ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) → 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) )
26 vex 𝑧 ∈ V
27 eqid 𝑧 = 𝑧
28 27 18 isref ( 𝑧 ∈ V → ( 𝑧 Ref 𝑦 ↔ ( 𝑦 = 𝑧 ∧ ∀ 𝑢𝑧𝑣𝑦 𝑢𝑣 ) ) )
29 26 28 ax-mp ( 𝑧 Ref 𝑦 ↔ ( 𝑦 = 𝑧 ∧ ∀ 𝑢𝑧𝑣𝑦 𝑢𝑣 ) )
30 29 simprbi ( 𝑧 Ref 𝑦 → ∀ 𝑢𝑧𝑣𝑦 𝑢𝑣 )
31 30 adantl ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) → ∀ 𝑢𝑧𝑣𝑦 𝑢𝑣 )
32 sseq2 ( 𝑣 = ( 𝑓𝑢 ) → ( 𝑢𝑣𝑢 ⊆ ( 𝑓𝑢 ) ) )
33 32 ac6sg ( 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) → ( ∀ 𝑢𝑧𝑣𝑦 𝑢𝑣 → ∃ 𝑓 ( 𝑓 : 𝑧𝑦 ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) ) )
34 25 31 33 sylc ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) → ∃ 𝑓 ( 𝑓 : 𝑧𝑦 ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) )
35 simplr ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑓 : 𝑧𝑦 )
36 35 frnd ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ran 𝑓𝑦 )
37 vex 𝑓 ∈ V
38 37 rnex ran 𝑓 ∈ V
39 38 elpw ( ran 𝑓 ∈ 𝒫 𝑦 ↔ ran 𝑓𝑦 )
40 36 39 sylibr ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ran 𝑓 ∈ 𝒫 𝑦 )
41 35 ffnd ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑓 Fn 𝑧 )
42 elin ( 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ↔ ( 𝑧 ∈ 𝒫 𝑗𝑧 ∈ Fin ) )
43 42 simprbi ( 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) → 𝑧 ∈ Fin )
44 43 ad4antlr ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑧 ∈ Fin )
45 fnfi ( ( 𝑓 Fn 𝑧𝑧 ∈ Fin ) → 𝑓 ∈ Fin )
46 41 44 45 syl2anc ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑓 ∈ Fin )
47 rnfi ( 𝑓 ∈ Fin → ran 𝑓 ∈ Fin )
48 46 47 syl ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ran 𝑓 ∈ Fin )
49 40 48 elind ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ran 𝑓 ∈ ( 𝒫 𝑦 ∩ Fin ) )
50 simp-5r ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑗 = 𝑦 )
51 27 18 refbas ( 𝑧 Ref 𝑦 𝑦 = 𝑧 )
52 51 ad3antlr ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑦 = 𝑧 )
53 nfv 𝑢 ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 )
54 nfra1 𝑢𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 )
55 53 54 nfan 𝑢 ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) )
56 rspa ( ( ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ∧ 𝑢𝑧 ) → 𝑢 ⊆ ( 𝑓𝑢 ) )
57 56 adantll ( ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) ∧ 𝑢𝑧 ) → 𝑢 ⊆ ( 𝑓𝑢 ) )
58 57 sseld ( ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) ∧ 𝑢𝑧 ) → ( 𝑥𝑢𝑥 ∈ ( 𝑓𝑢 ) ) )
59 58 ex ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ( 𝑢𝑧 → ( 𝑥𝑢𝑥 ∈ ( 𝑓𝑢 ) ) ) )
60 55 59 reximdai ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ( ∃ 𝑢𝑧 𝑥𝑢 → ∃ 𝑢𝑧 𝑥 ∈ ( 𝑓𝑢 ) ) )
61 eluni2 ( 𝑥 𝑧 ↔ ∃ 𝑢𝑧 𝑥𝑢 )
62 61 a1i ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ( 𝑥 𝑧 ↔ ∃ 𝑢𝑧 𝑥𝑢 ) )
63 fnunirn ( 𝑓 Fn 𝑧 → ( 𝑥 ran 𝑓 ↔ ∃ 𝑢𝑧 𝑥 ∈ ( 𝑓𝑢 ) ) )
64 41 63 syl ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ( 𝑥 ran 𝑓 ↔ ∃ 𝑢𝑧 𝑥 ∈ ( 𝑓𝑢 ) ) )
65 60 62 64 3imtr4d ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ( 𝑥 𝑧𝑥 ran 𝑓 ) )
66 65 ssrdv ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑧 ran 𝑓 )
67 52 66 eqsstrd ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑦 ran 𝑓 )
68 36 unissd ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ran 𝑓 𝑦 )
69 67 68 eqssd ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑦 = ran 𝑓 )
70 50 69 eqtrd ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → 𝑗 = ran 𝑓 )
71 unieq ( 𝑥 = ran 𝑓 𝑥 = ran 𝑓 )
72 71 rspceeqv ( ( ran 𝑓 ∈ ( 𝒫 𝑦 ∩ Fin ) ∧ 𝑗 = ran 𝑓 ) → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 )
73 49 70 72 syl2anc ( ( ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) ∧ 𝑓 : 𝑧𝑦 ) ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 )
74 73 expl ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) → ( ( 𝑓 : 𝑧𝑦 ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ) )
75 74 exlimdv ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) → ( ∃ 𝑓 ( 𝑓 : 𝑧𝑦 ∧ ∀ 𝑢𝑧 𝑢 ⊆ ( 𝑓𝑢 ) ) → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ) )
76 34 75 mpd ( ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) ) ∧ 𝑧 Ref 𝑦 ) → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 )
77 76 r19.29an ( ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) ∧ ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 ) → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 )
78 24 77 impbida ( ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) ∧ 𝑗 = 𝑦 ) → ( ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ↔ ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 ) )
79 78 pm5.74da ( ( 𝑗 ∈ Top ∧ 𝑦 ∈ 𝒫 𝑗 ) → ( ( 𝑗 = 𝑦 → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ) ↔ ( 𝑗 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 ) ) )
80 79 ralbidva ( 𝑗 ∈ Top → ( ∀ 𝑦 ∈ 𝒫 𝑗 ( 𝑗 = 𝑦 → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ) ↔ ∀ 𝑦 ∈ 𝒫 𝑗 ( 𝑗 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 ) ) )
81 80 pm5.32i ( ( 𝑗 ∈ Top ∧ ∀ 𝑦 ∈ 𝒫 𝑗 ( 𝑗 = 𝑦 → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ) ) ↔ ( 𝑗 ∈ Top ∧ ∀ 𝑦 ∈ 𝒫 𝑗 ( 𝑗 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 ) ) )
82 eqid 𝑗 = 𝑗
83 82 iscmp ( 𝑗 ∈ Comp ↔ ( 𝑗 ∈ Top ∧ ∀ 𝑦 ∈ 𝒫 𝑗 ( 𝑗 = 𝑦 → ∃ 𝑥 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝑗 = 𝑥 ) ) )
84 82 iscref ( 𝑗 ∈ CovHasRef Fin ↔ ( 𝑗 ∈ Top ∧ ∀ 𝑦 ∈ 𝒫 𝑗 ( 𝑗 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑗 ∩ Fin ) 𝑧 Ref 𝑦 ) ) )
85 81 83 84 3bitr4i ( 𝑗 ∈ Comp ↔ 𝑗 ∈ CovHasRef Fin )
86 85 eqriv Comp = CovHasRef Fin