Metamath Proof Explorer


Theorem rrxsphere

Description: The sphere with center M and radius R in a generalized real Euclidean space of finite dimension. Remark: this theorem holds also for the degenerate case R < 0 (negative radius): in this case, ( M S R ) is empty. (Contributed by AV, 5-Feb-2023)

Ref Expression
Hypotheses rrxspheres.e 𝐸 = ( ℝ^ ‘ 𝐼 )
rrxspheres.p 𝑃 = ( ℝ ↑m 𝐼 )
rrxspheres.d 𝐷 = ( dist ‘ 𝐸 )
rrxspheres.s 𝑆 = ( Sphere ‘ 𝐸 )
Assertion rrxsphere ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )

Proof

Step Hyp Ref Expression
1 rrxspheres.e 𝐸 = ( ℝ^ ‘ 𝐼 )
2 rrxspheres.p 𝑃 = ( ℝ ↑m 𝐼 )
3 rrxspheres.d 𝐷 = ( dist ‘ 𝐸 )
4 rrxspheres.s 𝑆 = ( Sphere ‘ 𝐸 )
5 1 fvexi 𝐸 ∈ V
6 id ( 𝐼 ∈ Fin → 𝐼 ∈ Fin )
7 eqid ( Base ‘ 𝐸 ) = ( Base ‘ 𝐸 )
8 6 1 7 rrxbasefi ( 𝐼 ∈ Fin → ( Base ‘ 𝐸 ) = ( ℝ ↑m 𝐼 ) )
9 2 8 eqtr4id ( 𝐼 ∈ Fin → 𝑃 = ( Base ‘ 𝐸 ) )
10 9 eleq2d ( 𝐼 ∈ Fin → ( 𝑀𝑃𝑀 ∈ ( Base ‘ 𝐸 ) ) )
11 10 biimpa ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃 ) → 𝑀 ∈ ( Base ‘ 𝐸 ) )
12 11 3adant3 ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → 𝑀 ∈ ( Base ‘ 𝐸 ) )
13 12 adantl ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → 𝑀 ∈ ( Base ‘ 𝐸 ) )
14 rexr ( 𝑅 ∈ ℝ → 𝑅 ∈ ℝ* )
15 14 3ad2ant3 ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → 𝑅 ∈ ℝ* )
16 15 anim2i ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → ( 0 ≤ 𝑅𝑅 ∈ ℝ* ) )
17 16 ancomd ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → ( 𝑅 ∈ ℝ* ∧ 0 ≤ 𝑅 ) )
18 elxrge0 ( 𝑅 ∈ ( 0 [,] +∞ ) ↔ ( 𝑅 ∈ ℝ* ∧ 0 ≤ 𝑅 ) )
19 17 18 sylibr ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → 𝑅 ∈ ( 0 [,] +∞ ) )
20 7 4 3 sphere ( ( 𝐸 ∈ V ∧ 𝑀 ∈ ( Base ‘ 𝐸 ) ∧ 𝑅 ∈ ( 0 [,] +∞ ) ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝 ∈ ( Base ‘ 𝐸 ) ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )
21 5 13 19 20 mp3an2i ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝 ∈ ( Base ‘ 𝐸 ) ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )
22 simp1 ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → 𝐼 ∈ Fin )
23 22 1 7 rrxbasefi ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( Base ‘ 𝐸 ) = ( ℝ ↑m 𝐼 ) )
24 23 2 eqtr4di ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( Base ‘ 𝐸 ) = 𝑃 )
25 24 adantl ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → ( Base ‘ 𝐸 ) = 𝑃 )
26 25 rabeqdv ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → { 𝑝 ∈ ( Base ‘ 𝐸 ) ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )
27 21 26 eqtrd ( ( 0 ≤ 𝑅 ∧ ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )
28 27 ex ( 0 ≤ 𝑅 → ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } ) )
29 7 4 3 spheres ( 𝐸 ∈ V → 𝑆 = ( 𝑥 ∈ ( Base ‘ 𝐸 ) , 𝑟 ∈ ( 0 [,] +∞ ) ↦ { 𝑝 ∈ ( Base ‘ 𝐸 ) ∣ ( 𝑝 𝐷 𝑥 ) = 𝑟 } ) )
30 5 29 ax-mp 𝑆 = ( 𝑥 ∈ ( Base ‘ 𝐸 ) , 𝑟 ∈ ( 0 [,] +∞ ) ↦ { 𝑝 ∈ ( Base ‘ 𝐸 ) ∣ ( 𝑝 𝐷 𝑥 ) = 𝑟 } )
31 fvex ( Base ‘ 𝐸 ) ∈ V
32 31 rabex { 𝑝 ∈ ( Base ‘ 𝐸 ) ∣ ( 𝑝 𝐷 𝑥 ) = 𝑟 } ∈ V
33 30 32 dmmpo dom 𝑆 = ( ( Base ‘ 𝐸 ) × ( 0 [,] +∞ ) )
34 0xr 0 ∈ ℝ*
35 pnfxr +∞ ∈ ℝ*
36 34 35 pm3.2i ( 0 ∈ ℝ* ∧ +∞ ∈ ℝ* )
37 elicc1 ( ( 0 ∈ ℝ* ∧ +∞ ∈ ℝ* ) → ( 𝑅 ∈ ( 0 [,] +∞ ) ↔ ( 𝑅 ∈ ℝ* ∧ 0 ≤ 𝑅𝑅 ≤ +∞ ) ) )
38 36 37 mp1i ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( 𝑅 ∈ ( 0 [,] +∞ ) ↔ ( 𝑅 ∈ ℝ* ∧ 0 ≤ 𝑅𝑅 ≤ +∞ ) ) )
39 simp2 ( ( 𝑅 ∈ ℝ* ∧ 0 ≤ 𝑅𝑅 ≤ +∞ ) → 0 ≤ 𝑅 )
40 38 39 syl6bi ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( 𝑅 ∈ ( 0 [,] +∞ ) → 0 ≤ 𝑅 ) )
41 40 con3d ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( ¬ 0 ≤ 𝑅 → ¬ 𝑅 ∈ ( 0 [,] +∞ ) ) )
42 41 imp ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) → ¬ 𝑅 ∈ ( 0 [,] +∞ ) )
43 42 intnand ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) → ¬ ( 𝑀 ∈ ( Base ‘ 𝐸 ) ∧ 𝑅 ∈ ( 0 [,] +∞ ) ) )
44 ndmovg ( ( dom 𝑆 = ( ( Base ‘ 𝐸 ) × ( 0 [,] +∞ ) ) ∧ ¬ ( 𝑀 ∈ ( Base ‘ 𝐸 ) ∧ 𝑅 ∈ ( 0 [,] +∞ ) ) ) → ( 𝑀 𝑆 𝑅 ) = ∅ )
45 33 43 44 sylancr ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) → ( 𝑀 𝑆 𝑅 ) = ∅ )
46 1 fveq2i ( dist ‘ 𝐸 ) = ( dist ‘ ( ℝ^ ‘ 𝐼 ) )
47 3 46 eqtri 𝐷 = ( dist ‘ ( ℝ^ ‘ 𝐼 ) )
48 47 rrxmetfi ( 𝐼 ∈ Fin → 𝐷 ∈ ( Met ‘ ( ℝ ↑m 𝐼 ) ) )
49 48 3ad2ant1 ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → 𝐷 ∈ ( Met ‘ ( ℝ ↑m 𝐼 ) ) )
50 49 adantr ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ 𝑝𝑃 ) → 𝐷 ∈ ( Met ‘ ( ℝ ↑m 𝐼 ) ) )
51 2 fveq2i ( Met ‘ 𝑃 ) = ( Met ‘ ( ℝ ↑m 𝐼 ) )
52 50 51 eleqtrrdi ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ 𝑝𝑃 ) → 𝐷 ∈ ( Met ‘ 𝑃 ) )
53 simpr ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ 𝑝𝑃 ) → 𝑝𝑃 )
54 simp2 ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → 𝑀𝑃 )
55 54 adantr ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ 𝑝𝑃 ) → 𝑀𝑃 )
56 metge0 ( ( 𝐷 ∈ ( Met ‘ 𝑃 ) ∧ 𝑝𝑃𝑀𝑃 ) → 0 ≤ ( 𝑝 𝐷 𝑀 ) )
57 52 53 55 56 syl3anc ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ 𝑝𝑃 ) → 0 ≤ ( 𝑝 𝐷 𝑀 ) )
58 breq2 ( ( 𝑝 𝐷 𝑀 ) = 𝑅 → ( 0 ≤ ( 𝑝 𝐷 𝑀 ) ↔ 0 ≤ 𝑅 ) )
59 57 58 syl5ibcom ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ 𝑝𝑃 ) → ( ( 𝑝 𝐷 𝑀 ) = 𝑅 → 0 ≤ 𝑅 ) )
60 59 con3d ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ 𝑝𝑃 ) → ( ¬ 0 ≤ 𝑅 → ¬ ( 𝑝 𝐷 𝑀 ) = 𝑅 ) )
61 60 impancom ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) → ( 𝑝𝑃 → ¬ ( 𝑝 𝐷 𝑀 ) = 𝑅 ) )
62 61 imp ( ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) ∧ 𝑝𝑃 ) → ¬ ( 𝑝 𝐷 𝑀 ) = 𝑅 )
63 62 ralrimiva ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) → ∀ 𝑝𝑃 ¬ ( 𝑝 𝐷 𝑀 ) = 𝑅 )
64 eqcom ( ∅ = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } ↔ { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } = ∅ )
65 rabeq0 ( { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } = ∅ ↔ ∀ 𝑝𝑃 ¬ ( 𝑝 𝐷 𝑀 ) = 𝑅 )
66 64 65 bitri ( ∅ = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } ↔ ∀ 𝑝𝑃 ¬ ( 𝑝 𝐷 𝑀 ) = 𝑅 )
67 63 66 sylibr ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) → ∅ = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )
68 45 67 eqtrd ( ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) ∧ ¬ 0 ≤ 𝑅 ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )
69 68 expcom ( ¬ 0 ≤ 𝑅 → ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } ) )
70 28 69 pm2.61i ( ( 𝐼 ∈ Fin ∧ 𝑀𝑃𝑅 ∈ ℝ ) → ( 𝑀 𝑆 𝑅 ) = { 𝑝𝑃 ∣ ( 𝑝 𝐷 𝑀 ) = 𝑅 } )