![]() |
Mathbox for Glauco Siliprandi |
< Previous
Next >
Nearby theorems |
|
Mirrors > Home > MPE Home > Th. List > Mathboxes > salunicl | Structured version Visualization version GIF version |
Description: SAlg sigma-algebra is closed under countable union. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
Ref | Expression |
---|---|
salunicl.s | ⊢ (𝜑 → 𝑆 ∈ SAlg) |
salunicl.t | ⊢ (𝜑 → 𝑇 ∈ 𝒫 𝑆) |
salunicl.tct | ⊢ (𝜑 → 𝑇 ≼ ω) |
Ref | Expression |
---|---|
salunicl | ⊢ (𝜑 → ∪ 𝑇 ∈ 𝑆) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | salunicl.tct | . 2 ⊢ (𝜑 → 𝑇 ≼ ω) | |
2 | breq1 5033 | . . . 4 ⊢ (𝑦 = 𝑇 → (𝑦 ≼ ω ↔ 𝑇 ≼ ω)) | |
3 | unieq 4811 | . . . . 5 ⊢ (𝑦 = 𝑇 → ∪ 𝑦 = ∪ 𝑇) | |
4 | 3 | eleq1d 2874 | . . . 4 ⊢ (𝑦 = 𝑇 → (∪ 𝑦 ∈ 𝑆 ↔ ∪ 𝑇 ∈ 𝑆)) |
5 | 2, 4 | imbi12d 348 | . . 3 ⊢ (𝑦 = 𝑇 → ((𝑦 ≼ ω → ∪ 𝑦 ∈ 𝑆) ↔ (𝑇 ≼ ω → ∪ 𝑇 ∈ 𝑆))) |
6 | salunicl.s | . . . . 5 ⊢ (𝜑 → 𝑆 ∈ SAlg) | |
7 | issal 42956 | . . . . . 6 ⊢ (𝑆 ∈ SAlg → (𝑆 ∈ SAlg ↔ (∅ ∈ 𝑆 ∧ ∀𝑦 ∈ 𝑆 (∪ 𝑆 ∖ 𝑦) ∈ 𝑆 ∧ ∀𝑦 ∈ 𝒫 𝑆(𝑦 ≼ ω → ∪ 𝑦 ∈ 𝑆)))) | |
8 | 6, 7 | syl 17 | . . . . 5 ⊢ (𝜑 → (𝑆 ∈ SAlg ↔ (∅ ∈ 𝑆 ∧ ∀𝑦 ∈ 𝑆 (∪ 𝑆 ∖ 𝑦) ∈ 𝑆 ∧ ∀𝑦 ∈ 𝒫 𝑆(𝑦 ≼ ω → ∪ 𝑦 ∈ 𝑆)))) |
9 | 6, 8 | mpbid 235 | . . . 4 ⊢ (𝜑 → (∅ ∈ 𝑆 ∧ ∀𝑦 ∈ 𝑆 (∪ 𝑆 ∖ 𝑦) ∈ 𝑆 ∧ ∀𝑦 ∈ 𝒫 𝑆(𝑦 ≼ ω → ∪ 𝑦 ∈ 𝑆))) |
10 | 9 | simp3d 1141 | . . 3 ⊢ (𝜑 → ∀𝑦 ∈ 𝒫 𝑆(𝑦 ≼ ω → ∪ 𝑦 ∈ 𝑆)) |
11 | salunicl.t | . . 3 ⊢ (𝜑 → 𝑇 ∈ 𝒫 𝑆) | |
12 | 5, 10, 11 | rspcdva 3573 | . 2 ⊢ (𝜑 → (𝑇 ≼ ω → ∪ 𝑇 ∈ 𝑆)) |
13 | 1, 12 | mpd 15 | 1 ⊢ (𝜑 → ∪ 𝑇 ∈ 𝑆) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ↔ wb 209 ∧ w3a 1084 = wceq 1538 ∈ wcel 2111 ∀wral 3106 ∖ cdif 3878 ∅c0 4243 𝒫 cpw 4497 ∪ cuni 4800 class class class wbr 5030 ωcom 7560 ≼ cdom 8490 SAlgcsalg 42950 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1797 ax-4 1811 ax-5 1911 ax-6 1970 ax-7 2015 ax-8 2113 ax-9 2121 ax-ext 2770 |
This theorem depends on definitions: df-bi 210 df-an 400 df-or 845 df-3an 1086 df-ex 1782 df-sb 2070 df-clab 2777 df-cleq 2791 df-clel 2870 df-ral 3111 df-rab 3115 df-v 3443 df-dif 3884 df-un 3886 df-in 3888 df-ss 3898 df-pw 4499 df-sn 4526 df-pr 4528 df-op 4532 df-uni 4801 df-br 5031 df-salg 42951 |
This theorem is referenced by: saliuncl 42964 intsal 42970 smfpimbor1lem1 43430 |
Copyright terms: Public domain | W3C validator |