Metamath Proof Explorer


Theorem baselcarsg

Description: The universe set, O , is Caratheodory measurable. (Contributed by Thierry Arnoux, 17-May-2020)

Ref Expression
Hypotheses carsgval.1 ⊢ ( 𝜑 → 𝑂 ∈ 𝑉 )
carsgval.2 ⊢ ( 𝜑 → 𝑀 : 𝒫 𝑂 ⟶ ( 0 [,] +∞ ) )
baselcarsg.1 ⊢ ( 𝜑 → ( 𝑀 ‘ ∅ ) = 0 )
Assertion baselcarsg ( 𝜑 → 𝑂 ∈ ( toCaraSiga ‘ 𝑀 ) )

Proof

Step Hyp Ref Expression
1 carsgval.1 ⊢ ( 𝜑 → 𝑂 ∈ 𝑉 )
2 carsgval.2 ⊢ ( 𝜑 → 𝑀 : 𝒫 𝑂 ⟶ ( 0 [,] +∞ ) )
3 baselcarsg.1 ⊢ ( 𝜑 → ( 𝑀 ‘ ∅ ) = 0 )
4 ssidd ⊢ ( 𝜑 → 𝑂 ⊆ 𝑂 )
5 elpwi ⊢ ( 𝑒 ∈ 𝒫 𝑂 → 𝑒 ⊆ 𝑂 )
6 5 adantl ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → 𝑒 ⊆ 𝑂 )
7 dfss2 ⊢ ( 𝑒 ⊆ 𝑂 ↔ ( 𝑒 ∩ 𝑂 ) = 𝑒 )
8 6 7 sylib ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑒 ∩ 𝑂 ) = 𝑒 )
9 8 fveq2d ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑀 ‘ ( 𝑒 ∩ 𝑂 ) ) = ( 𝑀 ‘ 𝑒 ) )
10 ssdif0 ⊢ ( 𝑒 ⊆ 𝑂 ↔ ( 𝑒 ∖ 𝑂 ) = ∅ )
11 6 10 sylib ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑒 ∖ 𝑂 ) = ∅ )
12 11 fveq2d ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑀 ‘ ( 𝑒 ∖ 𝑂 ) ) = ( 𝑀 ‘ ∅ ) )
13 3 adantr ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑀 ‘ ∅ ) = 0 )
14 12 13 eqtrd ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑀 ‘ ( 𝑒 ∖ 𝑂 ) ) = 0 )
15 9 14 oveq12d ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( ( 𝑀 ‘ ( 𝑒 ∩ 𝑂 ) ) +e ( 𝑀 ‘ ( 𝑒 ∖ 𝑂 ) ) ) = ( ( 𝑀 ‘ 𝑒 ) +e 0 ) )
16 iccssxr ⊢ ( 0 [,] +∞ ) ⊆ ℝ*
17 2 adantr ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → 𝑀 : 𝒫 𝑂 ⟶ ( 0 [,] +∞ ) )
18 simpr ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → 𝑒 ∈ 𝒫 𝑂 )
19 17 18 ffvelcdmd ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑀 ‘ 𝑒 ) ∈ ( 0 [,] +∞ ) )
20 16 19 sselid ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( 𝑀 ‘ 𝑒 ) ∈ ℝ* )
21 xaddrid ⊢ ( ( 𝑀 ‘ 𝑒 ) ∈ ℝ* → ( ( 𝑀 ‘ 𝑒 ) +e 0 ) = ( 𝑀 ‘ 𝑒 ) )
22 20 21 syl ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( ( 𝑀 ‘ 𝑒 ) +e 0 ) = ( 𝑀 ‘ 𝑒 ) )
23 15 22 eqtrd ⊢ ( ( 𝜑 ∧ 𝑒 ∈ 𝒫 𝑂 ) → ( ( 𝑀 ‘ ( 𝑒 ∩ 𝑂 ) ) +e ( 𝑀 ‘ ( 𝑒 ∖ 𝑂 ) ) ) = ( 𝑀 ‘ 𝑒 ) )
24 23 ralrimiva ⊢ ( 𝜑 → ∀ 𝑒 ∈ 𝒫 𝑂 ( ( 𝑀 ‘ ( 𝑒 ∩ 𝑂 ) ) +e ( 𝑀 ‘ ( 𝑒 ∖ 𝑂 ) ) ) = ( 𝑀 ‘ 𝑒 ) )
25 4 24 jca ⊢ ( 𝜑 → ( 𝑂 ⊆ 𝑂 ∧ ∀ 𝑒 ∈ 𝒫 𝑂 ( ( 𝑀 ‘ ( 𝑒 ∩ 𝑂 ) ) +e ( 𝑀 ‘ ( 𝑒 ∖ 𝑂 ) ) ) = ( 𝑀 ‘ 𝑒 ) ) )
26 1 2 elcarsg ⊢ ( 𝜑 → ( 𝑂 ∈ ( toCaraSiga ‘ 𝑀 ) ↔ ( 𝑂 ⊆ 𝑂 ∧ ∀ 𝑒 ∈ 𝒫 𝑂 ( ( 𝑀 ‘ ( 𝑒 ∩ 𝑂 ) ) +e ( 𝑀 ‘ ( 𝑒 ∖ 𝑂 ) ) ) = ( 𝑀 ‘ 𝑒 ) ) ) )
27 25 26 mpbird ⊢ ( 𝜑 → 𝑂 ∈ ( toCaraSiga ‘ 𝑀 ) )