Metamath Proof Explorer


Theorem cmpcovf

Description: Combine cmpcov with ac6sfi to show the existence of a function that indexes the elements that are generating the open cover. (Contributed by Mario Carneiro, 14-Sep-2014)

Ref Expression
Hypotheses iscmp.1 𝑋 = 𝐽
cmpcovf.2 ( 𝑧 = ( 𝑓𝑦 ) → ( 𝜑𝜓 ) )
Assertion cmpcovf ( ( 𝐽 ∈ Comp ∧ ∀ 𝑥𝑋𝑦𝐽 ( 𝑥𝑦 ∧ ∃ 𝑧𝐴 𝜑 ) ) → ∃ 𝑠 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) )

Proof

Step Hyp Ref Expression
1 iscmp.1 𝑋 = 𝐽
2 cmpcovf.2 ( 𝑧 = ( 𝑓𝑦 ) → ( 𝜑𝜓 ) )
3 simpl ( ( 𝐽 ∈ Comp ∧ ∀ 𝑥𝑋𝑦𝐽 ( 𝑥𝑦 ∧ ∃ 𝑧𝐴 𝜑 ) ) → 𝐽 ∈ Comp )
4 1 cmpcov2 ( ( 𝐽 ∈ Comp ∧ ∀ 𝑥𝑋𝑦𝐽 ( 𝑥𝑦 ∧ ∃ 𝑧𝐴 𝜑 ) ) → ∃ 𝑢 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) )
5 elfpw ( 𝑢 ∈ ( 𝒫 𝐽 ∩ Fin ) ↔ ( 𝑢𝐽𝑢 ∈ Fin ) )
6 simplrl ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → 𝑢𝐽 )
7 velpw ( 𝑢 ∈ 𝒫 𝐽𝑢𝐽 )
8 6 7 sylibr ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → 𝑢 ∈ 𝒫 𝐽 )
9 simplrr ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → 𝑢 ∈ Fin )
10 8 9 elind ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → 𝑢 ∈ ( 𝒫 𝐽 ∩ Fin ) )
11 simprl ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → 𝑋 = 𝑢 )
12 simprr ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → ∀ 𝑦𝑢𝑧𝐴 𝜑 )
13 2 ac6sfi ( ( 𝑢 ∈ Fin ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) → ∃ 𝑓 ( 𝑓 : 𝑢𝐴 ∧ ∀ 𝑦𝑢 𝜓 ) )
14 9 12 13 syl2anc ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → ∃ 𝑓 ( 𝑓 : 𝑢𝐴 ∧ ∀ 𝑦𝑢 𝜓 ) )
15 unieq ( 𝑠 = 𝑢 𝑠 = 𝑢 )
16 15 eqeq2d ( 𝑠 = 𝑢 → ( 𝑋 = 𝑠𝑋 = 𝑢 ) )
17 feq2 ( 𝑠 = 𝑢 → ( 𝑓 : 𝑠𝐴𝑓 : 𝑢𝐴 ) )
18 raleq ( 𝑠 = 𝑢 → ( ∀ 𝑦𝑠 𝜓 ↔ ∀ 𝑦𝑢 𝜓 ) )
19 17 18 anbi12d ( 𝑠 = 𝑢 → ( ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ↔ ( 𝑓 : 𝑢𝐴 ∧ ∀ 𝑦𝑢 𝜓 ) ) )
20 19 exbidv ( 𝑠 = 𝑢 → ( ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ↔ ∃ 𝑓 ( 𝑓 : 𝑢𝐴 ∧ ∀ 𝑦𝑢 𝜓 ) ) )
21 16 20 anbi12d ( 𝑠 = 𝑢 → ( ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) ↔ ( 𝑋 = 𝑢 ∧ ∃ 𝑓 ( 𝑓 : 𝑢𝐴 ∧ ∀ 𝑦𝑢 𝜓 ) ) ) )
22 21 rspcev ( ( 𝑢 ∈ ( 𝒫 𝐽 ∩ Fin ) ∧ ( 𝑋 = 𝑢 ∧ ∃ 𝑓 ( 𝑓 : 𝑢𝐴 ∧ ∀ 𝑦𝑢 𝜓 ) ) ) → ∃ 𝑠 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) )
23 10 11 14 22 syl12anc ( ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) ∧ ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) ) → ∃ 𝑠 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) )
24 23 ex ( ( 𝐽 ∈ Comp ∧ ( 𝑢𝐽𝑢 ∈ Fin ) ) → ( ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) → ∃ 𝑠 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) ) )
25 5 24 sylan2b ( ( 𝐽 ∈ Comp ∧ 𝑢 ∈ ( 𝒫 𝐽 ∩ Fin ) ) → ( ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) → ∃ 𝑠 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) ) )
26 25 rexlimdva ( 𝐽 ∈ Comp → ( ∃ 𝑢 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑢 ∧ ∀ 𝑦𝑢𝑧𝐴 𝜑 ) → ∃ 𝑠 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) ) )
27 3 4 26 sylc ( ( 𝐽 ∈ Comp ∧ ∀ 𝑥𝑋𝑦𝐽 ( 𝑥𝑦 ∧ ∃ 𝑧𝐴 𝜑 ) ) → ∃ 𝑠 ∈ ( 𝒫 𝐽 ∩ Fin ) ( 𝑋 = 𝑠 ∧ ∃ 𝑓 ( 𝑓 : 𝑠𝐴 ∧ ∀ 𝑦𝑠 𝜓 ) ) )