Metamath Proof Explorer


Theorem sitmcl

Description: Closure of the integral distance between two simple functions, for an extended metric space. (Contributed by Thierry Arnoux, 13-Feb-2018)

Ref Expression
Hypotheses sitmcl.0 ( 𝜑𝑊 ∈ Mnd )
sitmcl.1 ( 𝜑𝑊 ∈ ∞MetSp )
sitmcl.2 ( 𝜑𝑀 ran measures )
sitmcl.3 ( 𝜑𝐹 ∈ dom ( 𝑊 sitg 𝑀 ) )
sitmcl.4 ( 𝜑𝐺 ∈ dom ( 𝑊 sitg 𝑀 ) )
Assertion sitmcl ( 𝜑 → ( 𝐹 ( 𝑊 sitm 𝑀 ) 𝐺 ) ∈ ( 0 [,] +∞ ) )

Proof

Step Hyp Ref Expression
1 sitmcl.0 ( 𝜑𝑊 ∈ Mnd )
2 sitmcl.1 ( 𝜑𝑊 ∈ ∞MetSp )
3 sitmcl.2 ( 𝜑𝑀 ran measures )
4 sitmcl.3 ( 𝜑𝐹 ∈ dom ( 𝑊 sitg 𝑀 ) )
5 sitmcl.4 ( 𝜑𝐺 ∈ dom ( 𝑊 sitg 𝑀 ) )
6 eqid ( dist ‘ 𝑊 ) = ( dist ‘ 𝑊 )
7 6 2 3 4 5 sitmfval ( 𝜑 → ( 𝐹 ( 𝑊 sitm 𝑀 ) 𝐺 ) = ( ( ( ℝ*𝑠s ( 0 [,] +∞ ) ) sitg 𝑀 ) ‘ ( 𝐹f ( dist ‘ 𝑊 ) 𝐺 ) ) )
8 xrge0base ( 0 [,] +∞ ) = ( Base ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) )
9 xrge0topn ( TopOpen ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) ) = ( ( ordTop ‘ ≤ ) ↾t ( 0 [,] +∞ ) )
10 9 eqcomi ( ( ordTop ‘ ≤ ) ↾t ( 0 [,] +∞ ) ) = ( TopOpen ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) )
11 eqid ( sigaGen ‘ ( ( ordTop ‘ ≤ ) ↾t ( 0 [,] +∞ ) ) ) = ( sigaGen ‘ ( ( ordTop ‘ ≤ ) ↾t ( 0 [,] +∞ ) ) )
12 xrge00 0 = ( 0g ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) )
13 ovex ( 0 [,] +∞ ) ∈ V
14 eqid ( ℝ*𝑠s ( 0 [,] +∞ ) ) = ( ℝ*𝑠s ( 0 [,] +∞ ) )
15 ax-xrsvsca ·e = ( ·𝑠 ‘ ℝ*𝑠 )
16 14 15 ressvsca ( ( 0 [,] +∞ ) ∈ V → ·e = ( ·𝑠 ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) ) )
17 13 16 ax-mp ·e = ( ·𝑠 ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) )
18 ax-xrssca fld = ( Scalar ‘ ℝ*𝑠 )
19 14 18 resssca ( ( 0 [,] +∞ ) ∈ V → ℝfld = ( Scalar ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) ) )
20 13 19 ax-mp fld = ( Scalar ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) )
21 20 fveq2i ( ℝHom ‘ ℝfld ) = ( ℝHom ‘ ( Scalar ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) ) )
22 ovexd ( 𝜑 → ( ℝ*𝑠s ( 0 [,] +∞ ) ) ∈ V )
23 eqid ( Base ‘ 𝑊 ) = ( Base ‘ 𝑊 )
24 eqid ( TopOpen ‘ 𝑊 ) = ( TopOpen ‘ 𝑊 )
25 eqid ( sigaGen ‘ ( TopOpen ‘ 𝑊 ) ) = ( sigaGen ‘ ( TopOpen ‘ 𝑊 ) )
26 eqid ( 0g𝑊 ) = ( 0g𝑊 )
27 eqid ( ·𝑠𝑊 ) = ( ·𝑠𝑊 )
28 eqid ( ℝHom ‘ ( Scalar ‘ 𝑊 ) ) = ( ℝHom ‘ ( Scalar ‘ 𝑊 ) )
29 23 24 25 26 27 28 2 3 4 sibff ( 𝜑𝐹 : dom 𝑀 ( TopOpen ‘ 𝑊 ) )
30 xmstps ( 𝑊 ∈ ∞MetSp → 𝑊 ∈ TopSp )
31 23 24 tpsuni ( 𝑊 ∈ TopSp → ( Base ‘ 𝑊 ) = ( TopOpen ‘ 𝑊 ) )
32 2 30 31 3syl ( 𝜑 → ( Base ‘ 𝑊 ) = ( TopOpen ‘ 𝑊 ) )
33 feq3 ( ( Base ‘ 𝑊 ) = ( TopOpen ‘ 𝑊 ) → ( 𝐹 : dom 𝑀 ⟶ ( Base ‘ 𝑊 ) ↔ 𝐹 : dom 𝑀 ( TopOpen ‘ 𝑊 ) ) )
34 32 33 syl ( 𝜑 → ( 𝐹 : dom 𝑀 ⟶ ( Base ‘ 𝑊 ) ↔ 𝐹 : dom 𝑀 ( TopOpen ‘ 𝑊 ) ) )
35 29 34 mpbird ( 𝜑𝐹 : dom 𝑀 ⟶ ( Base ‘ 𝑊 ) )
36 23 24 25 26 27 28 2 3 5 sibff ( 𝜑𝐺 : dom 𝑀 ( TopOpen ‘ 𝑊 ) )
37 feq3 ( ( Base ‘ 𝑊 ) = ( TopOpen ‘ 𝑊 ) → ( 𝐺 : dom 𝑀 ⟶ ( Base ‘ 𝑊 ) ↔ 𝐺 : dom 𝑀 ( TopOpen ‘ 𝑊 ) ) )
38 32 37 syl ( 𝜑 → ( 𝐺 : dom 𝑀 ⟶ ( Base ‘ 𝑊 ) ↔ 𝐺 : dom 𝑀 ( TopOpen ‘ 𝑊 ) ) )
39 36 38 mpbird ( 𝜑𝐺 : dom 𝑀 ⟶ ( Base ‘ 𝑊 ) )
40 dmexg ( 𝑀 ran measures → dom 𝑀 ∈ V )
41 uniexg ( dom 𝑀 ∈ V → dom 𝑀 ∈ V )
42 3 40 41 3syl ( 𝜑 dom 𝑀 ∈ V )
43 35 39 42 ofresid ( 𝜑 → ( 𝐹f ( dist ‘ 𝑊 ) 𝐺 ) = ( 𝐹f ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) 𝐺 ) )
44 2 30 syl ( 𝜑𝑊 ∈ TopSp )
45 eqid ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) = ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) )
46 23 45 xmsxmet ( 𝑊 ∈ ∞MetSp → ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( ∞Met ‘ ( Base ‘ 𝑊 ) ) )
47 xmetpsmet ( ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( ∞Met ‘ ( Base ‘ 𝑊 ) ) → ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( PsMet ‘ ( Base ‘ 𝑊 ) ) )
48 2 46 47 3syl ( 𝜑 → ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( PsMet ‘ ( Base ‘ 𝑊 ) ) )
49 psmetxrge0 ( ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( PsMet ‘ ( Base ‘ 𝑊 ) ) → ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) : ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ⟶ ( 0 [,] +∞ ) )
50 48 49 syl ( 𝜑 → ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) : ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ⟶ ( 0 [,] +∞ ) )
51 xrge0tps ( ℝ*𝑠s ( 0 [,] +∞ ) ) ∈ TopSp
52 51 a1i ( 𝜑 → ( ℝ*𝑠s ( 0 [,] +∞ ) ) ∈ TopSp )
53 24 23 45 xmstopn ( 𝑊 ∈ ∞MetSp → ( TopOpen ‘ 𝑊 ) = ( MetOpen ‘ ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ) )
54 2 53 syl ( 𝜑 → ( TopOpen ‘ 𝑊 ) = ( MetOpen ‘ ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ) )
55 eqid ( MetOpen ‘ ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ) = ( MetOpen ‘ ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) )
56 55 methaus ( ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( ∞Met ‘ ( Base ‘ 𝑊 ) ) → ( MetOpen ‘ ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ) ∈ Haus )
57 2 46 56 3syl ( 𝜑 → ( MetOpen ‘ ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ) ∈ Haus )
58 54 57 eqeltrd ( 𝜑 → ( TopOpen ‘ 𝑊 ) ∈ Haus )
59 haust1 ( ( TopOpen ‘ 𝑊 ) ∈ Haus → ( TopOpen ‘ 𝑊 ) ∈ Fre )
60 58 59 syl ( 𝜑 → ( TopOpen ‘ 𝑊 ) ∈ Fre )
61 2 46 syl ( 𝜑 → ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( ∞Met ‘ ( Base ‘ 𝑊 ) ) )
62 23 26 mndidcl ( 𝑊 ∈ Mnd → ( 0g𝑊 ) ∈ ( Base ‘ 𝑊 ) )
63 1 62 syl ( 𝜑 → ( 0g𝑊 ) ∈ ( Base ‘ 𝑊 ) )
64 xmet0 ( ( ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ∈ ( ∞Met ‘ ( Base ‘ 𝑊 ) ) ∧ ( 0g𝑊 ) ∈ ( Base ‘ 𝑊 ) ) → ( ( 0g𝑊 ) ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ( 0g𝑊 ) ) = 0 )
65 61 63 64 syl2anc ( 𝜑 → ( ( 0g𝑊 ) ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ( 0g𝑊 ) ) = 0 )
66 65 12 eqtrdi ( 𝜑 → ( ( 0g𝑊 ) ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) ( 0g𝑊 ) ) = ( 0g ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) ) )
67 23 24 25 26 27 28 2 3 4 8 44 50 5 52 60 66 sibfof ( 𝜑 → ( 𝐹f ( ( dist ‘ 𝑊 ) ↾ ( ( Base ‘ 𝑊 ) × ( Base ‘ 𝑊 ) ) ) 𝐺 ) ∈ dom ( ( ℝ*𝑠s ( 0 [,] +∞ ) ) sitg 𝑀 ) )
68 43 67 eqeltrd ( 𝜑 → ( 𝐹f ( dist ‘ 𝑊 ) 𝐺 ) ∈ dom ( ( ℝ*𝑠s ( 0 [,] +∞ ) ) sitg 𝑀 ) )
69 rebase ℝ = ( Base ‘ ℝfld )
70 69 69 xpeq12i ( ℝ × ℝ ) = ( ( Base ‘ ℝfld ) × ( Base ‘ ℝfld ) )
71 70 reseq2i ( ( dist ‘ ℝfld ) ↾ ( ℝ × ℝ ) ) = ( ( dist ‘ ℝfld ) ↾ ( ( Base ‘ ℝfld ) × ( Base ‘ ℝfld ) ) )
72 xrge0cmn ( ℝ*𝑠s ( 0 [,] +∞ ) ) ∈ CMnd
73 72 a1i ( 𝜑 → ( ℝ*𝑠s ( 0 [,] +∞ ) ) ∈ CMnd )
74 rerrext fld ∈ ℝExt
75 20 74 eqeltrri ( Scalar ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) ) ∈ ℝExt
76 75 a1i ( 𝜑 → ( Scalar ‘ ( ℝ*𝑠s ( 0 [,] +∞ ) ) ) ∈ ℝExt )
77 rrhre ( ℝHom ‘ ℝfld ) = ( I ↾ ℝ )
78 77 imaeq1i ( ( ℝHom ‘ ℝfld ) “ ( 0 [,) +∞ ) ) = ( ( I ↾ ℝ ) “ ( 0 [,) +∞ ) )
79 0re 0 ∈ ℝ
80 pnfxr +∞ ∈ ℝ*
81 icossre ( ( 0 ∈ ℝ ∧ +∞ ∈ ℝ* ) → ( 0 [,) +∞ ) ⊆ ℝ )
82 79 80 81 mp2an ( 0 [,) +∞ ) ⊆ ℝ
83 resiima ( ( 0 [,) +∞ ) ⊆ ℝ → ( ( I ↾ ℝ ) “ ( 0 [,) +∞ ) ) = ( 0 [,) +∞ ) )
84 82 83 ax-mp ( ( I ↾ ℝ ) “ ( 0 [,) +∞ ) ) = ( 0 [,) +∞ )
85 78 84 eqtri ( ( ℝHom ‘ ℝfld ) “ ( 0 [,) +∞ ) ) = ( 0 [,) +∞ )
86 icossicc ( 0 [,) +∞ ) ⊆ ( 0 [,] +∞ )
87 85 86 eqsstri ( ( ℝHom ‘ ℝfld ) “ ( 0 [,) +∞ ) ) ⊆ ( 0 [,] +∞ )
88 87 sseli ( 𝑚 ∈ ( ( ℝHom ‘ ℝfld ) “ ( 0 [,) +∞ ) ) → 𝑚 ∈ ( 0 [,] +∞ ) )
89 88 3ad2ant2 ( ( 𝜑𝑚 ∈ ( ( ℝHom ‘ ℝfld ) “ ( 0 [,) +∞ ) ) ∧ 𝑥 ∈ ( 0 [,] +∞ ) ) → 𝑚 ∈ ( 0 [,] +∞ ) )
90 simp3 ( ( 𝜑𝑚 ∈ ( ( ℝHom ‘ ℝfld ) “ ( 0 [,) +∞ ) ) ∧ 𝑥 ∈ ( 0 [,] +∞ ) ) → 𝑥 ∈ ( 0 [,] +∞ ) )
91 ge0xmulcl ( ( 𝑚 ∈ ( 0 [,] +∞ ) ∧ 𝑥 ∈ ( 0 [,] +∞ ) ) → ( 𝑚 ·e 𝑥 ) ∈ ( 0 [,] +∞ ) )
92 89 90 91 syl2anc ( ( 𝜑𝑚 ∈ ( ( ℝHom ‘ ℝfld ) “ ( 0 [,) +∞ ) ) ∧ 𝑥 ∈ ( 0 [,] +∞ ) ) → ( 𝑚 ·e 𝑥 ) ∈ ( 0 [,] +∞ ) )
93 8 10 11 12 17 21 22 3 68 20 71 52 73 76 92 sitgclg ( 𝜑 → ( ( ( ℝ*𝑠s ( 0 [,] +∞ ) ) sitg 𝑀 ) ‘ ( 𝐹f ( dist ‘ 𝑊 ) 𝐺 ) ) ∈ ( 0 [,] +∞ ) )
94 7 93 eqeltrd ( 𝜑 → ( 𝐹 ( 𝑊 sitm 𝑀 ) 𝐺 ) ∈ ( 0 [,] +∞ ) )