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Type | Label | Description |
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Statement | ||
Theorem | meadjun 43101 | The measure of the union of two disjoint sets is the sum of the measures, Property 112C (a) of [Fremlin1] p. 15. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ (𝜑 → 𝐴 ∈ 𝑆) & ⊢ (𝜑 → 𝐵 ∈ 𝑆) & ⊢ (𝜑 → (𝐴 ∩ 𝐵) = ∅) ⇒ ⊢ (𝜑 → (𝑀‘(𝐴 ∪ 𝐵)) = ((𝑀‘𝐴) +𝑒 (𝑀‘𝐵))) | ||
Theorem | meassle 43102 | The measure of a set is greater than or equal to the measure of a subset, Property 112C (b) of [Fremlin1] p. 15. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ (𝜑 → 𝐴 ∈ 𝑆) & ⊢ (𝜑 → 𝐵 ∈ 𝑆) & ⊢ (𝜑 → 𝐴 ⊆ 𝐵) ⇒ ⊢ (𝜑 → (𝑀‘𝐴) ≤ (𝑀‘𝐵)) | ||
Theorem | meaunle 43103 | The measure of the union of two sets is less than or equal to the sum of the measures, Property 112C (c) of [Fremlin1] p. 15. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ (𝜑 → 𝐴 ∈ 𝑆) & ⊢ (𝜑 → 𝐵 ∈ 𝑆) ⇒ ⊢ (𝜑 → (𝑀‘(𝐴 ∪ 𝐵)) ≤ ((𝑀‘𝐴) +𝑒 (𝑀‘𝐵))) | ||
Theorem | meadjiunlem 43104* | The sum of nonnegative extended reals, restricted to the range of another function. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ (𝜑 → 𝑋 ∈ 𝑉) & ⊢ (𝜑 → 𝐺:𝑋⟶𝑆) & ⊢ 𝑌 = {𝑖 ∈ 𝑋 ∣ (𝐺‘𝑖) ≠ ∅} & ⊢ (𝜑 → Disj 𝑖 ∈ 𝑋 (𝐺‘𝑖)) ⇒ ⊢ (𝜑 → (Σ^‘(𝑀 ↾ ran 𝐺)) = (Σ^‘(𝑀 ∘ 𝐺))) | ||
Theorem | meadjiun 43105* | The measure of the disjoint union of a countable set is the extended sum of the measures. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ Ⅎ𝑘𝜑 & ⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ ((𝜑 ∧ 𝑘 ∈ 𝐴) → 𝐵 ∈ 𝑆) & ⊢ (𝜑 → 𝐴 ≼ ω) & ⊢ (𝜑 → Disj 𝑘 ∈ 𝐴 𝐵) ⇒ ⊢ (𝜑 → (𝑀‘∪ 𝑘 ∈ 𝐴 𝐵) = (Σ^‘(𝑘 ∈ 𝐴 ↦ (𝑀‘𝐵)))) | ||
Theorem | ismeannd 43106* | Sufficient condition to prove that 𝑀 is a measure. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑆 ∈ SAlg) & ⊢ (𝜑 → 𝑀:𝑆⟶(0[,]+∞)) & ⊢ (𝜑 → (𝑀‘∅) = 0) & ⊢ ((𝜑 ∧ 𝑒:ℕ⟶𝑆 ∧ Disj 𝑛 ∈ ℕ (𝑒‘𝑛)) → (𝑀‘∪ 𝑛 ∈ ℕ (𝑒‘𝑛)) = (Σ^‘(𝑛 ∈ ℕ ↦ (𝑀‘(𝑒‘𝑛))))) ⇒ ⊢ (𝜑 → 𝑀 ∈ Meas) | ||
Theorem | meaiunlelem 43107* | The measure of the union of countable sets is less than or equal to the sum of the measures, Property 112C (d) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ Ⅎ𝑛𝜑 & ⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶𝑆) & ⊢ 𝐹 = (𝑛 ∈ 𝑍 ↦ ((𝐸‘𝑛) ∖ ∪ 𝑖 ∈ (𝑁..^𝑛)(𝐸‘𝑖))) ⇒ ⊢ (𝜑 → (𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛)) ≤ (Σ^‘(𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))))) | ||
Theorem | meaiunle 43108* | The measure of the union of countable sets is less than or equal to the sum of the measures, Property 112C (d) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ Ⅎ𝑛𝜑 & ⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶𝑆) ⇒ ⊢ (𝜑 → (𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛)) ≤ (Σ^‘(𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))))) | ||
Theorem | psmeasurelem 43109* | 𝑀 applied to a disjoint union of subsets of its domain is the sum of 𝑀 applied to such subset. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑋 ∈ 𝑉) & ⊢ (𝜑 → 𝐻:𝑋⟶(0[,]+∞)) & ⊢ 𝑀 = (𝑥 ∈ 𝒫 𝑋 ↦ (Σ^‘(𝐻 ↾ 𝑥))) & ⊢ (𝜑 → 𝑀:𝒫 𝑋⟶(0[,]+∞)) & ⊢ (𝜑 → 𝑌 ⊆ 𝒫 𝑋) & ⊢ (𝜑 → Disj 𝑦 ∈ 𝑌 𝑦) ⇒ ⊢ (𝜑 → (𝑀‘∪ 𝑌) = (Σ^‘(𝑀 ↾ 𝑌))) | ||
Theorem | psmeasure 43110* | Point supported measure, Remark 112B (d) of [Fremlin1] p. 15. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑋 ∈ 𝑉) & ⊢ (𝜑 → 𝐻:𝑋⟶(0[,]+∞)) & ⊢ 𝑀 = (𝑥 ∈ 𝒫 𝑋 ↦ (Σ^‘(𝐻 ↾ 𝑥))) ⇒ ⊢ (𝜑 → 𝑀 ∈ Meas) | ||
Theorem | voliunsge0lem 43111* | The Lebesgue measure function is countably additive. (Contributed by Glauco Siliprandi, 3-Mar-2021.) |
⊢ 𝑆 = seq1( + , 𝐺) & ⊢ 𝐺 = (𝑛 ∈ ℕ ↦ (vol‘(𝐸‘𝑛))) & ⊢ (𝜑 → 𝐸:ℕ⟶dom vol) & ⊢ (𝜑 → Disj 𝑛 ∈ ℕ (𝐸‘𝑛)) ⇒ ⊢ (𝜑 → (vol‘∪ 𝑛 ∈ ℕ (𝐸‘𝑛)) = (Σ^‘(𝑛 ∈ ℕ ↦ (vol‘(𝐸‘𝑛))))) | ||
Theorem | voliunsge0 43112* | The Lebesgue measure function is countably additive. (Contributed by Glauco Siliprandi, 3-Mar-2021.) |
⊢ (𝜑 → 𝐸:ℕ⟶dom vol) & ⊢ (𝜑 → Disj 𝑛 ∈ ℕ (𝐸‘𝑛)) ⇒ ⊢ (𝜑 → (vol‘∪ 𝑛 ∈ ℕ (𝐸‘𝑛)) = (Σ^‘(𝑛 ∈ ℕ ↦ (vol‘(𝐸‘𝑛))))) | ||
Theorem | volmea 43113 | The Lebeasgue measure on the Reals is actually a measure. (Contributed by Glauco Siliprandi, 3-Mar-2021.) |
⊢ (𝜑 → vol ∈ Meas) | ||
Theorem | meage0 43114 | If the measure of a measurable set is greater than or equal to 0. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝐴 ∈ dom 𝑀) ⇒ ⊢ (𝜑 → 0 ≤ (𝑀‘𝐴)) | ||
Theorem | meadjunre 43115 | The measure of the union of two disjoint sets, with finite measure, is the sum of the measures, Property 112C (a) of [Fremlin1] p. 15. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ 𝑆 = dom 𝑀 & ⊢ (𝜑 → 𝐴 ∈ 𝑆) & ⊢ (𝜑 → 𝐵 ∈ 𝑆) & ⊢ (𝜑 → (𝐴 ∩ 𝐵) = ∅) & ⊢ (𝜑 → (𝑀‘𝐴) ∈ ℝ) & ⊢ (𝜑 → (𝑀‘𝐵) ∈ ℝ) ⇒ ⊢ (𝜑 → (𝑀‘(𝐴 ∪ 𝐵)) = ((𝑀‘𝐴) + (𝑀‘𝐵))) | ||
Theorem | meassre 43116 | If the measure of a measurable set is real, then the measure of any of its measurable subsets is real. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝐴 ∈ dom 𝑀) & ⊢ (𝜑 → (𝑀‘𝐴) ∈ ℝ) & ⊢ (𝜑 → 𝐵 ⊆ 𝐴) & ⊢ (𝜑 → 𝐵 ∈ dom 𝑀) ⇒ ⊢ (𝜑 → (𝑀‘𝐵) ∈ ℝ) | ||
Theorem | meale0eq0 43117 | A measure that is less than or equal to 0 is 0. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝐴 ∈ dom 𝑀) & ⊢ (𝜑 → (𝑀‘𝐴) ≤ 0) ⇒ ⊢ (𝜑 → (𝑀‘𝐴) = 0) | ||
Theorem | meadif 43118 | The measure of the difference of two sets. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝐴 ∈ dom 𝑀) & ⊢ (𝜑 → (𝑀‘𝐴) ∈ ℝ) & ⊢ (𝜑 → 𝐵 ∈ dom 𝑀) & ⊢ (𝜑 → 𝐵 ⊆ 𝐴) ⇒ ⊢ (𝜑 → (𝑀‘(𝐴 ∖ 𝐵)) = ((𝑀‘𝐴) − (𝑀‘𝐵))) | ||
Theorem | meaiuninclem 43119* | Measures are continuous from below (bounded case): if 𝐸 is a sequence of increasing measurable sets (with uniformly bounded measure) then the measure of the union is the union of the measure. This is Proposition 112C (e) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘𝑛) ⊆ (𝐸‘(𝑛 + 1))) & ⊢ (𝜑 → ∃𝑥 ∈ ℝ ∀𝑛 ∈ 𝑍 (𝑀‘(𝐸‘𝑛)) ≤ 𝑥) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) & ⊢ 𝐹 = (𝑛 ∈ 𝑍 ↦ ((𝐸‘𝑛) ∖ ∪ 𝑖 ∈ (𝑁..^𝑛)(𝐸‘𝑖))) ⇒ ⊢ (𝜑 → 𝑆 ⇝ (𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiuninc 43120* | Measures are continuous from below (bounded case): if 𝐸 is a sequence of nondecreasing measurable sets (with bounded measure) then the measure of the union is the limit of the measures. This is Proposition 112C (e) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘𝑛) ⊆ (𝐸‘(𝑛 + 1))) & ⊢ (𝜑 → ∃𝑥 ∈ ℝ ∀𝑛 ∈ 𝑍 (𝑀‘(𝐸‘𝑛)) ≤ 𝑥) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) ⇒ ⊢ (𝜑 → 𝑆 ⇝ (𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiuninc2 43121* | Measures are continuous from below (bounded case): if 𝐸 is a sequence of nondecreasing measurable sets (with bounded measure) then the measure of the union is the limit of the measures. This is Proposition 112C (e) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘𝑛) ⊆ (𝐸‘(𝑛 + 1))) & ⊢ (𝜑 → 𝐵 ∈ ℝ) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝑀‘(𝐸‘𝑛)) ≤ 𝐵) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) ⇒ ⊢ (𝜑 → 𝑆 ⇝ (𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiunincf 43122* | Measures are continuous from below (bounded case): if 𝐸 is a sequence of nondecreasing measurable sets (with bounded measure) then the measure of the union is the limit of the measures. This is Proposition 112C (e) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 13-Feb-2022.) |
⊢ Ⅎ𝑛𝜑 & ⊢ Ⅎ𝑛𝐸 & ⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘𝑛) ⊆ (𝐸‘(𝑛 + 1))) & ⊢ (𝜑 → ∃𝑥 ∈ ℝ ∀𝑛 ∈ 𝑍 (𝑀‘(𝐸‘𝑛)) ≤ 𝑥) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) ⇒ ⊢ (𝜑 → 𝑆 ⇝ (𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiuninc3v 43123* | Measures are continuous from below: if 𝐸 is a sequence of nondecreasing measurable sets (with bounded measure) then the measure of the union is the limit of the measures. This is the general case of Proposition 112C (e) of [Fremlin1] p. 16 . This theorem generalizes meaiuninc 43120 and meaiuninc2 43121 where the sequence is required to be bounded. (Contributed by Glauco Siliprandi, 13-Feb-2022.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘𝑛) ⊆ (𝐸‘(𝑛 + 1))) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) ⇒ ⊢ (𝜑 → 𝑆~~>*(𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiuninc3 43124* | Measures are continuous from below: if 𝐸 is a sequence of nondecreasing measurable sets (with bounded measure) then the measure of the union is the limit of the measures. This is the general case of Proposition 112C (e) of [Fremlin1] p. 16 . This theorem generalizes meaiuninc 43120 and meaiuninc2 43121 where the sequence is required to be bounded. (Contributed by Glauco Siliprandi, 13-Feb-2022.) |
⊢ Ⅎ𝑛𝜑 & ⊢ Ⅎ𝑛𝐸 & ⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘𝑛) ⊆ (𝐸‘(𝑛 + 1))) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) ⇒ ⊢ (𝜑 → 𝑆~~>*(𝑀‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiininclem 43125* | Measures are continuous from above: if 𝐸 is a nonincreasing sequence of measurable sets, and any of the sets has finite measure, then the measure of the intersection is the limit of the measures. This is Proposition 112C (f) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘(𝑛 + 1)) ⊆ (𝐸‘𝑛)) & ⊢ (𝜑 → 𝐾 ∈ (ℤ≥‘𝑁)) & ⊢ (𝜑 → (𝑀‘(𝐸‘𝐾)) ∈ ℝ) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) & ⊢ 𝐺 = (𝑛 ∈ 𝑍 ↦ ((𝐸‘𝐾) ∖ (𝐸‘𝑛))) & ⊢ 𝐹 = ∪ 𝑛 ∈ 𝑍 (𝐺‘𝑛) ⇒ ⊢ (𝜑 → 𝑆 ⇝ (𝑀‘∩ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiininc 43126* | Measures are continuous from above: if 𝐸 is a nonincreasing sequence of measurable sets, and any of the sets has finite measure, then the measure of the intersection is the limit of the measures. This is Proposition 112C (f) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ Ⅎ𝑛𝜑 & ⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘(𝑛 + 1)) ⊆ (𝐸‘𝑛)) & ⊢ (𝜑 → 𝐾 ∈ (ℤ≥‘𝑁)) & ⊢ (𝜑 → (𝑀‘(𝐸‘𝐾)) ∈ ℝ) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) ⇒ ⊢ (𝜑 → 𝑆 ⇝ (𝑀‘∩ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Theorem | meaiininc2 43127* | Measures are continuous from above: if 𝐸 is a nonincreasing sequence of measurable sets, and any of the sets has finite measure, then the measure of the intersection is the limit of the measures. This is Proposition 112C (f) of [Fremlin1] p. 16. (Contributed by Glauco Siliprandi, 8-Apr-2021.) |
⊢ Ⅎ𝑛𝜑 & ⊢ Ⅎ𝑘𝜑 & ⊢ (𝜑 → 𝑀 ∈ Meas) & ⊢ (𝜑 → 𝑁 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶dom 𝑀) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → (𝐸‘(𝑛 + 1)) ⊆ (𝐸‘𝑛)) & ⊢ (𝜑 → ∃𝑘 ∈ 𝑍 (𝑀‘(𝐸‘𝑘)) ∈ ℝ) & ⊢ 𝑆 = (𝑛 ∈ 𝑍 ↦ (𝑀‘(𝐸‘𝑛))) ⇒ ⊢ (𝜑 → 𝑆 ⇝ (𝑀‘∩ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) | ||
Proofs for most of the theorems in section 113 of [Fremlin1] | ||
Syntax | come 43128 | Extend class notation with the class of outer measures. |
class OutMeas | ||
Definition | df-ome 43129* | Define the class of outer measures. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ OutMeas = {𝑥 ∣ ((((𝑥:dom 𝑥⟶(0[,]+∞) ∧ dom 𝑥 = 𝒫 ∪ dom 𝑥) ∧ (𝑥‘∅) = 0) ∧ ∀𝑦 ∈ 𝒫 ∪ dom 𝑥∀𝑧 ∈ 𝒫 𝑦(𝑥‘𝑧) ≤ (𝑥‘𝑦)) ∧ ∀𝑦 ∈ 𝒫 dom 𝑥(𝑦 ≼ ω → (𝑥‘∪ 𝑦) ≤ (Σ^‘(𝑥 ↾ 𝑦))))} | ||
Syntax | ccaragen 43130 | Extend class notation with a function that takes an outer measure and generates a sigma-algebra and a measure. |
class CaraGen | ||
Definition | df-caragen 43131* | Define the sigma-algebra generated by an outer measure. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ CaraGen = (𝑜 ∈ OutMeas ↦ {𝑒 ∈ 𝒫 ∪ dom 𝑜 ∣ ∀𝑎 ∈ 𝒫 ∪ dom 𝑜((𝑜‘(𝑎 ∩ 𝑒)) +𝑒 (𝑜‘(𝑎 ∖ 𝑒))) = (𝑜‘𝑎)}) | ||
Theorem | caragenval 43132* | The sigma-algebra generated by an outer measure. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝑂 ∈ OutMeas → (CaraGen‘𝑂) = {𝑒 ∈ 𝒫 ∪ dom 𝑂 ∣ ∀𝑎 ∈ 𝒫 ∪ dom 𝑂((𝑂‘(𝑎 ∩ 𝑒)) +𝑒 (𝑂‘(𝑎 ∖ 𝑒))) = (𝑂‘𝑎)}) | ||
Theorem | isome 43133* | Express the predicate "𝑂 is an outer measure." Definition 113A of [Fremlin1] p. 19. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝑂 ∈ 𝑉 → (𝑂 ∈ OutMeas ↔ ((((𝑂:dom 𝑂⟶(0[,]+∞) ∧ dom 𝑂 = 𝒫 ∪ dom 𝑂) ∧ (𝑂‘∅) = 0) ∧ ∀𝑦 ∈ 𝒫 ∪ dom 𝑂∀𝑧 ∈ 𝒫 𝑦(𝑂‘𝑧) ≤ (𝑂‘𝑦)) ∧ ∀𝑦 ∈ 𝒫 dom 𝑂(𝑦 ≼ ω → (𝑂‘∪ 𝑦) ≤ (Σ^‘(𝑂 ↾ 𝑦)))))) | ||
Theorem | caragenel 43134* | Membership in the Caratheodory's construction. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → (𝐸 ∈ 𝑆 ↔ (𝐸 ∈ 𝒫 ∪ dom 𝑂 ∧ ∀𝑎 ∈ 𝒫 ∪ dom 𝑂((𝑂‘(𝑎 ∩ 𝐸)) +𝑒 (𝑂‘(𝑎 ∖ 𝐸))) = (𝑂‘𝑎)))) | ||
Theorem | omef 43135 | An outer measure is a function that maps to nonnegative extended reals. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 ⇒ ⊢ (𝜑 → 𝑂:𝒫 𝑋⟶(0[,]+∞)) | ||
Theorem | ome0 43136 | The outer measure of the empty set is 0 . (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) ⇒ ⊢ (𝜑 → (𝑂‘∅) = 0) | ||
Theorem | omessle 43137 | The outer measure of a set is greater than or equal to the measure of a subset, Definition 113A (ii) of [Fremlin1] p. 19. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐵 ⊆ 𝑋) & ⊢ (𝜑 → 𝐴 ⊆ 𝐵) ⇒ ⊢ (𝜑 → (𝑂‘𝐴) ≤ (𝑂‘𝐵)) | ||
Theorem | omedm 43138 | The domain of an outer measure is a power set. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝑂 ∈ OutMeas → dom 𝑂 = 𝒫 ∪ dom 𝑂) | ||
Theorem | caragensplit 43139 | If 𝐸 is in the set generated by the Caratheodory's method, then it splits any set 𝐴 in two parts such that the sum of the outer measures of the two parts is equal to the outer measure of the whole set 𝐴. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐸 ∈ 𝑆) & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) ⇒ ⊢ (𝜑 → ((𝑂‘(𝐴 ∩ 𝐸)) +𝑒 (𝑂‘(𝐴 ∖ 𝐸))) = (𝑂‘𝐴)) | ||
Theorem | caragenelss 43140 | An element of the Caratheodory's construction is a subset of the base set of the outer measure. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐴 ∈ 𝑆) & ⊢ 𝑋 = ∪ dom 𝑂 ⇒ ⊢ (𝜑 → 𝐴 ⊆ 𝑋) | ||
Theorem | carageneld 43141* | Membership in the Caratheodory's construction. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐸 ∈ 𝒫 𝑋) & ⊢ ((𝜑 ∧ 𝑎 ∈ 𝒫 𝑋) → ((𝑂‘(𝑎 ∩ 𝐸)) +𝑒 (𝑂‘(𝑎 ∖ 𝐸))) = (𝑂‘𝑎)) ⇒ ⊢ (𝜑 → 𝐸 ∈ 𝑆) | ||
Theorem | omecl 43142 | The outer measure of a set is a nonnegative extended real. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) ⇒ ⊢ (𝜑 → (𝑂‘𝐴) ∈ (0[,]+∞)) | ||
Theorem | caragenss 43143 | The sigma-algebra generated from an outer measure, by the Caratheodory's construction, is a subset of the domain of the outer measure. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝑂 ∈ OutMeas → 𝑆 ⊆ dom 𝑂) | ||
Theorem | omeunile 43144 | The outer measure of the union of a countable set is the less than or equal to the extended sum of the outer measures. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝑌 ⊆ 𝒫 𝑋) & ⊢ (𝜑 → 𝑌 ≼ ω) ⇒ ⊢ (𝜑 → (𝑂‘∪ 𝑌) ≤ (Σ^‘(𝑂 ↾ 𝑌))) | ||
Theorem | caragen0 43145 | The empty set belongs to any Caratheodory's construction. First part of Step (b) in the proof of Theorem 113C of [Fremlin1] p. 19. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → ∅ ∈ 𝑆) | ||
Theorem | omexrcl 43146 | The outer measure of a set is an extended real. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) ⇒ ⊢ (𝜑 → (𝑂‘𝐴) ∈ ℝ*) | ||
Theorem | caragenunidm 43147 | The base set of an outer measure belongs to the sigma-algebra generated by the Caratheodory's construction. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → 𝑋 ∈ 𝑆) | ||
Theorem | caragensspw 43148 | The sigma-algebra generated from an outer measure, by the Caratheodory's construction, is a subset of the power set of the base set of the outer measure. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → 𝑆 ⊆ 𝒫 𝑋) | ||
Theorem | omessre 43149 | If the outer measure of a set is real, then the outer measure of any of its subset is real. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) & ⊢ (𝜑 → (𝑂‘𝐴) ∈ ℝ) & ⊢ (𝜑 → 𝐵 ⊆ 𝐴) ⇒ ⊢ (𝜑 → (𝑂‘𝐵) ∈ ℝ) | ||
Theorem | caragenuni 43150 | The base set of the sigma-algebra generated by the Caratheodory's construction is the whole base set of the original outer measure. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → ∪ 𝑆 = ∪ dom 𝑂) | ||
Theorem | caragenuncllem 43151 | The Caratheodory's construction is closed under the union. Step (c) in the proof of Theorem 113C of [Fremlin1] p. 20. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐸 ∈ 𝑆) & ⊢ (𝜑 → 𝐹 ∈ 𝑆) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) ⇒ ⊢ (𝜑 → ((𝑂‘(𝐴 ∩ (𝐸 ∪ 𝐹))) +𝑒 (𝑂‘(𝐴 ∖ (𝐸 ∪ 𝐹)))) = (𝑂‘𝐴)) | ||
Theorem | caragenuncl 43152 | The Caratheodory's construction is closed under the union. Step (c) in the proof of Theorem 113C of [Fremlin1] p. 20. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐸 ∈ 𝑆) & ⊢ (𝜑 → 𝐹 ∈ 𝑆) ⇒ ⊢ (𝜑 → (𝐸 ∪ 𝐹) ∈ 𝑆) | ||
Theorem | caragendifcl 43153 | The Caratheodory's construction is closed under the complement operation. Second part of Step (b) in the proof of Theorem 113C of [Fremlin1] p. 19. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐸 ∈ 𝑆) ⇒ ⊢ (𝜑 → (∪ 𝑆 ∖ 𝐸) ∈ 𝑆) | ||
Theorem | caragenfiiuncl 43154* | The Caratheodory's construction is closed under finite indexed union. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ Ⅎ𝑘𝜑 & ⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐴 ∈ Fin) & ⊢ ((𝜑 ∧ 𝑘 ∈ 𝐴) → 𝐵 ∈ 𝑆) ⇒ ⊢ (𝜑 → ∪ 𝑘 ∈ 𝐴 𝐵 ∈ 𝑆) | ||
Theorem | omeunle 43155 | The outer measure of the union of two sets is less than or equal to the sum of the measures, Remark 113B (c) of [Fremlin1] p. 19. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) & ⊢ (𝜑 → 𝐵 ⊆ 𝑋) ⇒ ⊢ (𝜑 → (𝑂‘(𝐴 ∪ 𝐵)) ≤ ((𝑂‘𝐴) +𝑒 (𝑂‘𝐵))) | ||
Theorem | omeiunle 43156* | The outer measure of the indexed union of a countable set is the less than or equal to the extended sum of the outer measures. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ Ⅎ𝑛𝜑 & ⊢ Ⅎ𝑛𝐸 & ⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶𝒫 𝑋) ⇒ ⊢ (𝜑 → (𝑂‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛)) ≤ (Σ^‘(𝑛 ∈ 𝑍 ↦ (𝑂‘(𝐸‘𝑛))))) | ||
Theorem | omelesplit 43157 | The outer measure of a set 𝐴 is less than or equal to the extended addition of the outer measures of the decomposition induced on 𝐴 by any 𝐸. Step (a) in the proof of Caratheodory's Method, Theorem 113C of [Fremlin1] p. 19. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) ⇒ ⊢ (𝜑 → (𝑂‘𝐴) ≤ ((𝑂‘(𝐴 ∩ 𝐸)) +𝑒 (𝑂‘(𝐴 ∖ 𝐸)))) | ||
Theorem | omeiunltfirp 43158* | If the outer measure of a countable union is not +∞, then it can be arbitrarily approximated by finite sums of outer measures. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ (𝜑 → 𝐸:𝑍⟶𝒫 𝑋) & ⊢ (𝜑 → (𝑂‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛)) ∈ ℝ) & ⊢ (𝜑 → 𝑌 ∈ ℝ+) ⇒ ⊢ (𝜑 → ∃𝑧 ∈ (𝒫 𝑍 ∩ Fin)(𝑂‘∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛)) < (Σ𝑛 ∈ 𝑧 (𝑂‘(𝐸‘𝑛)) + 𝑌)) | ||
Theorem | omeiunlempt 43159* | The outer measure of the indexed union of a countable set is the less than or equal to the extended sum of the outer measures. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ Ⅎ𝑛𝜑 & ⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑍 = (ℤ≥‘𝑁) & ⊢ ((𝜑 ∧ 𝑛 ∈ 𝑍) → 𝐸 ⊆ 𝑋) ⇒ ⊢ (𝜑 → (𝑂‘∪ 𝑛 ∈ 𝑍 𝐸) ≤ (Σ^‘(𝑛 ∈ 𝑍 ↦ (𝑂‘𝐸)))) | ||
Theorem | carageniuncllem1 43160* | The outer measure of 𝐴 ∩ (𝐺‘𝑛) is the sum of the outer measures of 𝐴 ∩ (𝐹‘𝑚). These are lines 7 to 10 of Step (d) in the proof of Theorem 113C of [Fremlin1] p. 20. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) & ⊢ (𝜑 → (𝑂‘𝐴) ∈ ℝ) & ⊢ 𝑍 = (ℤ≥‘𝑀) & ⊢ (𝜑 → 𝐸:𝑍⟶𝑆) & ⊢ 𝐺 = (𝑛 ∈ 𝑍 ↦ ∪ 𝑖 ∈ (𝑀...𝑛)(𝐸‘𝑖)) & ⊢ 𝐹 = (𝑛 ∈ 𝑍 ↦ ((𝐸‘𝑛) ∖ ∪ 𝑖 ∈ (𝑀..^𝑛)(𝐸‘𝑖))) & ⊢ (𝜑 → 𝐾 ∈ 𝑍) ⇒ ⊢ (𝜑 → Σ𝑛 ∈ (𝑀...𝐾)(𝑂‘(𝐴 ∩ (𝐹‘𝑛))) = (𝑂‘(𝐴 ∩ (𝐺‘𝐾)))) | ||
Theorem | carageniuncllem2 43161* | The Caratheodory's construction is closed under countable union. Step (d) in the proof of Theorem 113C of [Fremlin1] p. 20. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) & ⊢ (𝜑 → (𝑂‘𝐴) ∈ ℝ) & ⊢ (𝜑 → 𝑀 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑀) & ⊢ (𝜑 → 𝐸:𝑍⟶𝑆) & ⊢ (𝜑 → 𝑌 ∈ ℝ+) & ⊢ 𝐺 = (𝑛 ∈ 𝑍 ↦ ∪ 𝑖 ∈ (𝑀...𝑛)(𝐸‘𝑖)) & ⊢ 𝐹 = (𝑛 ∈ 𝑍 ↦ ((𝐸‘𝑛) ∖ ∪ 𝑖 ∈ (𝑀..^𝑛)(𝐸‘𝑖))) ⇒ ⊢ (𝜑 → ((𝑂‘(𝐴 ∩ ∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛))) +𝑒 (𝑂‘(𝐴 ∖ ∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛)))) ≤ ((𝑂‘𝐴) + 𝑌)) | ||
Theorem | carageniuncl 43162* | The Caratheodory's construction is closed under indexed countable union. Step (d) in the proof of Theorem 113C of [Fremlin1] p. 20. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝑀 ∈ ℤ) & ⊢ 𝑍 = (ℤ≥‘𝑀) & ⊢ (𝜑 → 𝐸:𝑍⟶𝑆) ⇒ ⊢ (𝜑 → ∪ 𝑛 ∈ 𝑍 (𝐸‘𝑛) ∈ 𝑆) | ||
Theorem | caragenunicl 43163 | The Caratheodory's construction is closed under countable union. Step (d) in the proof of Theorem 113C of [Fremlin1] p. 20. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝑋 ⊆ 𝑆) & ⊢ (𝜑 → 𝑋 ≼ ω) ⇒ ⊢ (𝜑 → ∪ 𝑋 ∈ 𝑆) | ||
Theorem | caragensal 43164 | Caratheodory's method generates a sigma-algebra. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → 𝑆 ∈ SAlg) | ||
Theorem | caratheodorylem1 43165* | Lemma used to prove that Caratheodory's construction is sigma-additive. This is the proof of the statement in the middle of Step (e) in the proof of Theorem 113C of [Fremlin1] p. 21. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ 𝑍 = (ℤ≥‘𝑀) & ⊢ (𝜑 → 𝐸:𝑍⟶𝑆) & ⊢ (𝜑 → Disj 𝑛 ∈ 𝑍 (𝐸‘𝑛)) & ⊢ 𝐺 = (𝑛 ∈ 𝑍 ↦ ∪ 𝑖 ∈ (𝑀...𝑛)(𝐸‘𝑖)) & ⊢ (𝜑 → 𝑁 ∈ (ℤ≥‘𝑀)) ⇒ ⊢ (𝜑 → (𝑂‘(𝐺‘𝑁)) = (Σ^‘(𝑛 ∈ (𝑀...𝑁) ↦ (𝑂‘(𝐸‘𝑛))))) | ||
Theorem | caratheodorylem2 43166* | Caratheodory's construction is sigma-additive. Main part of Step (e) in the proof of Theorem 113C of [Fremlin1] p. 21. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐸:ℕ⟶𝑆) & ⊢ (𝜑 → Disj 𝑛 ∈ ℕ (𝐸‘𝑛)) & ⊢ 𝐺 = (𝑘 ∈ ℕ ↦ ∪ 𝑛 ∈ (1...𝑘)(𝐸‘𝑛)) ⇒ ⊢ (𝜑 → (𝑂‘∪ 𝑛 ∈ ℕ (𝐸‘𝑛)) = (Σ^‘(𝑛 ∈ ℕ ↦ (𝑂‘(𝐸‘𝑛))))) | ||
Theorem | caratheodory 43167 | Caratheodory's construction of a measure given an outer measure. Proof of Theorem 113C of [Fremlin1] p. 19. (Contributed by Glauco Siliprandi, 17-Aug-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → (𝑂 ↾ 𝑆) ∈ Meas) | ||
Theorem | 0ome 43168* | The map that assigns 0 to every subset, is an outer measure. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ 𝑉) & ⊢ 𝑂 = (𝑥 ∈ 𝒫 𝑋 ↦ 0) ⇒ ⊢ (𝜑 → 𝑂 ∈ OutMeas) | ||
Theorem | isomenndlem 43169* | 𝑂 is sub-additive w.r.t. countable indexed union, implies that 𝑂 is sub-additive w.r.t. countable union. Thus, the definition of Outer Measure can be given using an indexed union. Definition 113A of [Fremlin1] p. 19 . (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑂:𝒫 𝑋⟶(0[,]+∞)) & ⊢ (𝜑 → (𝑂‘∅) = 0) & ⊢ (𝜑 → 𝑌 ⊆ 𝒫 𝑋) & ⊢ ((𝜑 ∧ 𝑎:ℕ⟶𝒫 𝑋) → (𝑂‘∪ 𝑛 ∈ ℕ (𝑎‘𝑛)) ≤ (Σ^‘(𝑛 ∈ ℕ ↦ (𝑂‘(𝑎‘𝑛))))) & ⊢ (𝜑 → 𝐵 ⊆ ℕ) & ⊢ (𝜑 → 𝐹:𝐵–1-1-onto→𝑌) & ⊢ 𝐴 = (𝑛 ∈ ℕ ↦ if(𝑛 ∈ 𝐵, (𝐹‘𝑛), ∅)) ⇒ ⊢ (𝜑 → (𝑂‘∪ 𝑌) ≤ (Σ^‘(𝑂 ↾ 𝑌))) | ||
Theorem | isomennd 43170* | Sufficient condition to prove that 𝑂 is an outer measure. Definition 113A of [Fremlin1] p. 19 . (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ 𝑉) & ⊢ (𝜑 → 𝑂:𝒫 𝑋⟶(0[,]+∞)) & ⊢ (𝜑 → (𝑂‘∅) = 0) & ⊢ ((𝜑 ∧ 𝑥 ⊆ 𝑋 ∧ 𝑦 ⊆ 𝑥) → (𝑂‘𝑦) ≤ (𝑂‘𝑥)) & ⊢ ((𝜑 ∧ 𝑎:ℕ⟶𝒫 𝑋) → (𝑂‘∪ 𝑛 ∈ ℕ (𝑎‘𝑛)) ≤ (Σ^‘(𝑛 ∈ ℕ ↦ (𝑂‘(𝑎‘𝑛))))) ⇒ ⊢ (𝜑 → 𝑂 ∈ OutMeas) | ||
Theorem | caragenel2d 43171* | Membership in the Caratheodory's construction. Similar to carageneld 43141, but here "less then or equal to" is used, instead of equality. This is Remark 113D of [Fremlin1] p. 21. (Contributed by Glauco Siliprandi, 24-Dec-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ 𝑆 = (CaraGen‘𝑂) & ⊢ (𝜑 → 𝐸 ∈ 𝒫 𝑋) & ⊢ ((𝜑 ∧ 𝑎 ∈ 𝒫 𝑋) → ((𝑂‘(𝑎 ∩ 𝐸)) +𝑒 (𝑂‘(𝑎 ∖ 𝐸))) ≤ (𝑂‘𝑎)) ⇒ ⊢ (𝜑 → 𝐸 ∈ 𝑆) | ||
Theorem | omege0 43172 | If the outer measure of a set is greater than or equal to 0. (Contributed by Glauco Siliprandi, 24-Dec-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) ⇒ ⊢ (𝜑 → 0 ≤ (𝑂‘𝐴)) | ||
Theorem | omess0 43173 | If the outer measure of a set is 0, then the outer measure of its subsets is 0. (Contributed by Glauco Siliprandi, 24-Dec-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐴 ⊆ 𝑋) & ⊢ (𝜑 → (𝑂‘𝐴) = 0) & ⊢ (𝜑 → 𝐵 ⊆ 𝐴) ⇒ ⊢ (𝜑 → (𝑂‘𝐵) = 0) | ||
Theorem | caragencmpl 43174 | A measure built with the Caratheodory's construction is complete. See Definition 112Df of [Fremlin1] p. 19. This is Exercise 113Xa of [Fremlin1] p. 21. (Contributed by Glauco Siliprandi, 24-Dec-2020.) |
⊢ (𝜑 → 𝑂 ∈ OutMeas) & ⊢ 𝑋 = ∪ dom 𝑂 & ⊢ (𝜑 → 𝐸 ⊆ 𝑋) & ⊢ (𝜑 → (𝑂‘𝐸) = 0) & ⊢ 𝑆 = (CaraGen‘𝑂) ⇒ ⊢ (𝜑 → 𝐸 ∈ 𝑆) | ||
Proofs for most of the theorems in section 115 of [Fremlin1] | ||
Syntax | covoln 43175 | Extend class notation with the class of Lebesgue outer measure for the space of multidimensional real numbers. |
class voln* | ||
Definition | df-ovoln 43176* | Define the outer measure for the space of multidimensional real numbers. The cardinality of 𝑥 is the dimension of the space modeled. Definition 115C of [Fremlin1] p. 30. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ voln* = (𝑥 ∈ Fin ↦ (𝑦 ∈ 𝒫 (ℝ ↑m 𝑥) ↦ if(𝑥 = ∅, 0, inf({𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑥) ↑m ℕ)(𝑦 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑥 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑥 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))}, ℝ*, < )))) | ||
Syntax | cvoln 43177 | Extend class notation with the class of Lebesgue measure for the space of multidimensional real numbers. |
class voln | ||
Definition | df-voln 43178 | Define the Lebesgue measure for the space of multidimensional real numbers. The cardinality of 𝑥 is the dimension of the space modeled. Definition 115C of [Fremlin1] p. 30. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ voln = (𝑥 ∈ Fin ↦ ((voln*‘𝑥) ↾ (CaraGen‘(voln*‘𝑥)))) | ||
Theorem | vonval 43179 | Value of the Lebesgue measure for a given finite dimension. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) ⇒ ⊢ (𝜑 → (voln‘𝑋) = ((voln*‘𝑋) ↾ (CaraGen‘(voln*‘𝑋)))) | ||
Theorem | ovnval 43180* | Value of the Lebesgue outer measure for a given finite dimension. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) ⇒ ⊢ (𝜑 → (voln*‘𝑋) = (𝑦 ∈ 𝒫 (ℝ ↑m 𝑋) ↦ if(𝑋 = ∅, 0, inf({𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝑦 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))}, ℝ*, < )))) | ||
Theorem | elhoi 43181* | Membership in a multidimensional half-open interval. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ 𝑉) ⇒ ⊢ (𝜑 → (𝑌 ∈ ((𝐴[,)𝐵) ↑m 𝑋) ↔ (𝑌:𝑋⟶ℝ* ∧ ∀𝑥 ∈ 𝑋 (𝑌‘𝑥) ∈ (𝐴[,)𝐵)))) | ||
Theorem | icoresmbl 43182 | A closed-below, open-above real interval is measurable, when the bounds are real. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ ran ([,) ↾ (ℝ × ℝ)) ⊆ dom vol | ||
Theorem | hoissre 43183* | The projection of a half-open interval onto a single dimension is a subset of ℝ. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝐼:𝑋⟶(ℝ × ℝ)) ⇒ ⊢ ((𝜑 ∧ 𝑘 ∈ 𝑋) → (([,) ∘ 𝐼)‘𝑘) ⊆ ℝ) | ||
Theorem | ovnval2 43184* | Value of the Lebesgue outer measure of a subset 𝐴 of the space of multidimensional real numbers. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝐴 ⊆ (ℝ ↑m 𝑋)) & ⊢ 𝑀 = {𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝐴 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))} ⇒ ⊢ (𝜑 → ((voln*‘𝑋)‘𝐴) = if(𝑋 = ∅, 0, inf(𝑀, ℝ*, < ))) | ||
Theorem | volicorecl 43185 | The Lebesgue measure of a left-closed, right-open interval with real bounds, is real. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (vol‘(𝐴[,)𝐵)) ∈ ℝ) | ||
Theorem | hoiprodcl 43186* | The pre-measure of half-open intervals is a nonnegative real. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ Ⅎ𝑘𝜑 & ⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝐼:𝑋⟶(ℝ × ℝ)) ⇒ ⊢ (𝜑 → ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ 𝐼)‘𝑘)) ∈ (0[,)+∞)) | ||
Theorem | hoicvr 43187* | 𝐼 is a countable set of half-open intervals that covers the whole multidimensional reals. See Definition 1135 (b) of [Fremlin1] p. 29. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ 𝐼 = (𝑗 ∈ ℕ ↦ (𝑥 ∈ 𝑋 ↦ 〈-𝑗, 𝑗〉)) & ⊢ (𝜑 → 𝑋 ∈ Fin) ⇒ ⊢ (𝜑 → (ℝ ↑m 𝑋) ⊆ ∪ 𝑗 ∈ ℕ X𝑖 ∈ 𝑋 (([,) ∘ (𝐼‘𝑗))‘𝑖)) | ||
Theorem | hoissrrn 43188* | A half-open interval is a subset of R^n . (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝐼:𝑋⟶(ℝ × ℝ)) ⇒ ⊢ (𝜑 → X𝑘 ∈ 𝑋 (([,) ∘ 𝐼)‘𝑘) ⊆ (ℝ ↑m 𝑋)) | ||
Theorem | ovn0val 43189 | The Lebesgue outer measure (for the zero dimensional space of reals) of every subset is zero. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝐴 ⊆ (ℝ ↑m ∅)) ⇒ ⊢ (𝜑 → ((voln*‘∅)‘𝐴) = 0) | ||
Theorem | ovnn0val 43190* | The value of a (multidimensional) Lebesgue outer measure, defined on a nonzero-dimensional space of reals. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝑋 ≠ ∅) & ⊢ (𝜑 → 𝐴 ⊆ (ℝ ↑m 𝑋)) & ⊢ 𝑀 = {𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝐴 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))} ⇒ ⊢ (𝜑 → ((voln*‘𝑋)‘𝐴) = inf(𝑀, ℝ*, < )) | ||
Theorem | ovnval2b 43191* | Value of the Lebesgue outer measure of a subset 𝐴 of the space of multidimensional real numbers. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝐴 ⊆ (ℝ ↑m 𝑋)) & ⊢ 𝐿 = (𝑎 ∈ 𝒫 (ℝ ↑m 𝑋) ↦ {𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝑎 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))}) ⇒ ⊢ (𝜑 → ((voln*‘𝑋)‘𝐴) = if(𝑋 = ∅, 0, inf((𝐿‘𝐴), ℝ*, < ))) | ||
Theorem | volicorescl 43192 | The Lebesgue measure of a left-closed, right-open interval with real bounds, is real. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝐴 ∈ ran ([,) ↾ (ℝ × ℝ)) → (vol‘𝐴) ∈ ℝ) | ||
Theorem | ovnprodcl 43193* | The product used in the definition of the outer Lebesgue measure in R^n is a nonnegative real. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ Ⅎ𝑘𝜑 & ⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝐹:ℕ⟶((ℝ × ℝ) ↑m 𝑋)) & ⊢ (𝜑 → 𝐼 ∈ ℕ) ⇒ ⊢ (𝜑 → ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝐹‘𝐼))‘𝑘)) ∈ (0[,)+∞)) | ||
Theorem | hoiprodcl2 43194* | The pre-measure of half-open intervals is a nonnegative real. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ Ⅎ𝑘𝜑 & ⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ 𝐿 = (𝑖 ∈ ((ℝ × ℝ) ↑m 𝑋) ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ 𝑖)‘𝑘))) & ⊢ (𝜑 → 𝐼:𝑋⟶(ℝ × ℝ)) ⇒ ⊢ (𝜑 → (𝐿‘𝐼) ∈ (0[,)+∞)) | ||
Theorem | hoicvrrex 43195* | Any subset of the multidimensional reals can be covered by a countable set of half-open intervals, see Definition 115A (b) of [Fremlin1] p. 29. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝑌 ⊆ (ℝ ↑m 𝑋)) ⇒ ⊢ (𝜑 → ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝑌 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ +∞ = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))) | ||
Theorem | ovnsupge0 43196* | The set used in the definition of the Lebesgue outer measure is a subset of the nonnegative extended reals. This is a substep for (a)(i) of the proof of Proposition 115D (a) of [Fremlin1] p. 30. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝐴 ⊆ (ℝ ↑m 𝑋)) & ⊢ 𝑀 = {𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝐴 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))} ⇒ ⊢ (𝜑 → 𝑀 ⊆ (0[,]+∞)) | ||
Theorem | ovnlecvr 43197* | Given a subset of multidimensional reals and a set of half-open intervals that covers it, the Lebesgue outer measure of the set is bounded by the generalized sum of the pre-measure of the half-open intervals. The statement would also be true with 𝑋 the empty set, but covers are not used for the zero-dimensional case. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝑋 ≠ ∅) & ⊢ 𝐿 = (𝑖 ∈ ((ℝ × ℝ) ↑m 𝑋) ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ 𝑖)‘𝑘))) & ⊢ (𝜑 → 𝐼:ℕ⟶((ℝ × ℝ) ↑m 𝑋)) & ⊢ (𝜑 → 𝐴 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝐼‘𝑗))‘𝑘)) ⇒ ⊢ (𝜑 → ((voln*‘𝑋)‘𝐴) ≤ (Σ^‘(𝑗 ∈ ℕ ↦ (𝐿‘(𝐼‘𝑗))))) | ||
Theorem | ovnpnfelsup 43198* | +∞ is an element of the set used in the definition of the Lebesgue outer measure. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝐴 ⊆ (ℝ ↑m 𝑋)) & ⊢ 𝑀 = {𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝐴 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))} ⇒ ⊢ (𝜑 → +∞ ∈ 𝑀) | ||
Theorem | ovnsslelem 43199* | The (multidimensional, nonzero-dimensional) Lebesgue outer measure of a subset is less than the L.o.m. of the whole set. This is step (iii) of the proof of Proposition 115D (a) of [Fremlin1] p. 30. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝑋 ≠ ∅) & ⊢ (𝜑 → 𝐴 ⊆ 𝐵) & ⊢ (𝜑 → 𝐵 ⊆ (ℝ ↑m 𝑋)) & ⊢ 𝑀 = {𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝐴 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))} & ⊢ 𝑁 = {𝑧 ∈ ℝ* ∣ ∃𝑖 ∈ (((ℝ × ℝ) ↑m 𝑋) ↑m ℕ)(𝐵 ⊆ ∪ 𝑗 ∈ ℕ X𝑘 ∈ 𝑋 (([,) ∘ (𝑖‘𝑗))‘𝑘) ∧ 𝑧 = (Σ^‘(𝑗 ∈ ℕ ↦ ∏𝑘 ∈ 𝑋 (vol‘(([,) ∘ (𝑖‘𝑗))‘𝑘)))))} ⇒ ⊢ (𝜑 → ((voln*‘𝑋)‘𝐴) ≤ ((voln*‘𝑋)‘𝐵)) | ||
Theorem | ovnssle 43200 | The (multidimensional) Lebesgue outer measure of a subset is less than the L.o.m. of the whole set. This is step (iii) of the proof of Proposition 115D (a) of [Fremlin1] p. 30. (Contributed by Glauco Siliprandi, 11-Oct-2020.) |
⊢ (𝜑 → 𝑋 ∈ Fin) & ⊢ (𝜑 → 𝐴 ⊆ 𝐵) & ⊢ (𝜑 → 𝐵 ⊆ (ℝ ↑m 𝑋)) ⇒ ⊢ (𝜑 → ((voln*‘𝑋)‘𝐴) ≤ ((voln*‘𝑋)‘𝐵)) |
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