Metamath Proof Explorer


Theorem omssubaddlem

Description: For any small margin E , we can find a covering approaching the outer measure of a set A by that margin. (Contributed by Thierry Arnoux, 18-Sep-2019) (Revised by AV, 4-Oct-2020)

Ref Expression
Hypotheses oms.m 𝑀 = ( toOMeas ‘ 𝑅 )
oms.o ( 𝜑𝑄𝑉 )
oms.r ( 𝜑𝑅 : 𝑄 ⟶ ( 0 [,] +∞ ) )
omssubaddlem.a ( 𝜑𝐴 𝑄 )
omssubaddlem.m ( 𝜑 → ( 𝑀𝐴 ) ∈ ℝ )
omssubaddlem.e ( 𝜑𝐸 ∈ ℝ+ )
Assertion omssubaddlem ( 𝜑 → ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } Σ* 𝑤𝑥 ( 𝑅𝑤 ) < ( ( 𝑀𝐴 ) + 𝐸 ) )

Proof

Step Hyp Ref Expression
1 oms.m 𝑀 = ( toOMeas ‘ 𝑅 )
2 oms.o ( 𝜑𝑄𝑉 )
3 oms.r ( 𝜑𝑅 : 𝑄 ⟶ ( 0 [,] +∞ ) )
4 omssubaddlem.a ( 𝜑𝐴 𝑄 )
5 omssubaddlem.m ( 𝜑 → ( 𝑀𝐴 ) ∈ ℝ )
6 omssubaddlem.e ( 𝜑𝐸 ∈ ℝ+ )
7 6 rpred ( 𝜑𝐸 ∈ ℝ )
8 5 7 readdcld ( 𝜑 → ( ( 𝑀𝐴 ) + 𝐸 ) ∈ ℝ )
9 8 rexrd ( 𝜑 → ( ( 𝑀𝐴 ) + 𝐸 ) ∈ ℝ* )
10 omsf ( ( 𝑄𝑉𝑅 : 𝑄 ⟶ ( 0 [,] +∞ ) ) → ( toOMeas ‘ 𝑅 ) : 𝒫 dom 𝑅 ⟶ ( 0 [,] +∞ ) )
11 2 3 10 syl2anc ( 𝜑 → ( toOMeas ‘ 𝑅 ) : 𝒫 dom 𝑅 ⟶ ( 0 [,] +∞ ) )
12 1 feq1i ( 𝑀 : 𝒫 dom 𝑅 ⟶ ( 0 [,] +∞ ) ↔ ( toOMeas ‘ 𝑅 ) : 𝒫 dom 𝑅 ⟶ ( 0 [,] +∞ ) )
13 11 12 sylibr ( 𝜑𝑀 : 𝒫 dom 𝑅 ⟶ ( 0 [,] +∞ ) )
14 3 fdmd ( 𝜑 → dom 𝑅 = 𝑄 )
15 14 unieqd ( 𝜑 dom 𝑅 = 𝑄 )
16 4 15 sseqtrrd ( 𝜑𝐴 dom 𝑅 )
17 2 uniexd ( 𝜑 𝑄 ∈ V )
18 4 17 jca ( 𝜑 → ( 𝐴 𝑄 𝑄 ∈ V ) )
19 ssexg ( ( 𝐴 𝑄 𝑄 ∈ V ) → 𝐴 ∈ V )
20 elpwg ( 𝐴 ∈ V → ( 𝐴 ∈ 𝒫 dom 𝑅𝐴 dom 𝑅 ) )
21 18 19 20 3syl ( 𝜑 → ( 𝐴 ∈ 𝒫 dom 𝑅𝐴 dom 𝑅 ) )
22 16 21 mpbird ( 𝜑𝐴 ∈ 𝒫 dom 𝑅 )
23 13 22 ffvelrnd ( 𝜑 → ( 𝑀𝐴 ) ∈ ( 0 [,] +∞ ) )
24 elxrge0 ( ( 𝑀𝐴 ) ∈ ( 0 [,] +∞ ) ↔ ( ( 𝑀𝐴 ) ∈ ℝ* ∧ 0 ≤ ( 𝑀𝐴 ) ) )
25 24 simprbi ( ( 𝑀𝐴 ) ∈ ( 0 [,] +∞ ) → 0 ≤ ( 𝑀𝐴 ) )
26 23 25 syl ( 𝜑 → 0 ≤ ( 𝑀𝐴 ) )
27 6 rpge0d ( 𝜑 → 0 ≤ 𝐸 )
28 5 7 26 27 addge0d ( 𝜑 → 0 ≤ ( ( 𝑀𝐴 ) + 𝐸 ) )
29 elxrge0 ( ( ( 𝑀𝐴 ) + 𝐸 ) ∈ ( 0 [,] +∞ ) ↔ ( ( ( 𝑀𝐴 ) + 𝐸 ) ∈ ℝ* ∧ 0 ≤ ( ( 𝑀𝐴 ) + 𝐸 ) ) )
30 9 28 29 sylanbrc ( 𝜑 → ( ( 𝑀𝐴 ) + 𝐸 ) ∈ ( 0 [,] +∞ ) )
31 1 fveq1i ( 𝑀𝐴 ) = ( ( toOMeas ‘ 𝑅 ) ‘ 𝐴 )
32 omsfval ( ( 𝑄𝑉𝑅 : 𝑄 ⟶ ( 0 [,] +∞ ) ∧ 𝐴 𝑄 ) → ( ( toOMeas ‘ 𝑅 ) ‘ 𝐴 ) = inf ( ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) , ( 0 [,] +∞ ) , < ) )
33 2 3 4 32 syl3anc ( 𝜑 → ( ( toOMeas ‘ 𝑅 ) ‘ 𝐴 ) = inf ( ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) , ( 0 [,] +∞ ) , < ) )
34 31 33 eqtr2id ( 𝜑 → inf ( ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) , ( 0 [,] +∞ ) , < ) = ( 𝑀𝐴 ) )
35 5 6 ltaddrpd ( 𝜑 → ( 𝑀𝐴 ) < ( ( 𝑀𝐴 ) + 𝐸 ) )
36 34 35 eqbrtrd ( 𝜑 → inf ( ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) , ( 0 [,] +∞ ) , < ) < ( ( 𝑀𝐴 ) + 𝐸 ) )
37 iccssxr ( 0 [,] +∞ ) ⊆ ℝ*
38 xrltso < Or ℝ*
39 soss ( ( 0 [,] +∞ ) ⊆ ℝ* → ( < Or ℝ* → < Or ( 0 [,] +∞ ) ) )
40 37 38 39 mp2 < Or ( 0 [,] +∞ )
41 40 a1i ( 𝜑 → < Or ( 0 [,] +∞ ) )
42 omscl ( ( 𝑄𝑉𝑅 : 𝑄 ⟶ ( 0 [,] +∞ ) ∧ 𝐴 ∈ 𝒫 dom 𝑅 ) → ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ⊆ ( 0 [,] +∞ ) )
43 2 3 22 42 syl3anc ( 𝜑 → ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ⊆ ( 0 [,] +∞ ) )
44 xrge0infss ( ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ⊆ ( 0 [,] +∞ ) → ∃ 𝑒 ∈ ( 0 [,] +∞ ) ( ∀ 𝑡 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ¬ 𝑡 < 𝑒 ∧ ∀ 𝑡 ∈ ( 0 [,] +∞ ) ( 𝑒 < 𝑡 → ∃ 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) 𝑢 < 𝑡 ) ) )
45 43 44 syl ( 𝜑 → ∃ 𝑒 ∈ ( 0 [,] +∞ ) ( ∀ 𝑡 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ¬ 𝑡 < 𝑒 ∧ ∀ 𝑡 ∈ ( 0 [,] +∞ ) ( 𝑒 < 𝑡 → ∃ 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) 𝑢 < 𝑡 ) ) )
46 41 45 infglb ( 𝜑 → ( ( ( ( 𝑀𝐴 ) + 𝐸 ) ∈ ( 0 [,] +∞ ) ∧ inf ( ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) , ( 0 [,] +∞ ) , < ) < ( ( 𝑀𝐴 ) + 𝐸 ) ) → ∃ 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
47 30 36 46 mp2and ( 𝜑 → ∃ 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) )
48 eqid ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) = ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) )
49 esumex Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∈ V
50 48 49 elrnmpti ( 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ↔ ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) )
51 50 anbi1i ( ( 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) ↔ ( ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
52 r19.41v ( ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) ↔ ( ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
53 51 52 bitr4i ( ( 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) ↔ ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
54 53 exbii ( ∃ 𝑢 ( 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) ↔ ∃ 𝑢𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
55 df-rex ( ∃ 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ↔ ∃ 𝑢 ( 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
56 rexcom4 ( ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ∃ 𝑢 ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) ↔ ∃ 𝑢𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
57 54 55 56 3bitr4i ( ∃ 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ↔ ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ∃ 𝑢 ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
58 breq1 ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) → ( 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ↔ Σ* 𝑤𝑥 ( 𝑅𝑤 ) < ( ( 𝑀𝐴 ) + 𝐸 ) ) )
59 58 biimpa ( ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) → Σ* 𝑤𝑥 ( 𝑅𝑤 ) < ( ( 𝑀𝐴 ) + 𝐸 ) )
60 59 exlimiv ( ∃ 𝑢 ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) → Σ* 𝑤𝑥 ( 𝑅𝑤 ) < ( ( 𝑀𝐴 ) + 𝐸 ) )
61 60 reximi ( ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ∃ 𝑢 ( 𝑢 = Σ* 𝑤𝑥 ( 𝑅𝑤 ) ∧ 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) ) → ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } Σ* 𝑤𝑥 ( 𝑅𝑤 ) < ( ( 𝑀𝐴 ) + 𝐸 ) )
62 57 61 sylbi ( ∃ 𝑢 ∈ ran ( 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } ↦ Σ* 𝑤𝑥 ( 𝑅𝑤 ) ) 𝑢 < ( ( 𝑀𝐴 ) + 𝐸 ) → ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } Σ* 𝑤𝑥 ( 𝑅𝑤 ) < ( ( 𝑀𝐴 ) + 𝐸 ) )
63 47 62 syl ( 𝜑 → ∃ 𝑥 ∈ { 𝑧 ∈ 𝒫 dom 𝑅 ∣ ( 𝐴 𝑧𝑧 ≼ ω ) } Σ* 𝑤𝑥 ( 𝑅𝑤 ) < ( ( 𝑀𝐴 ) + 𝐸 ) )