Metamath Proof Explorer


Theorem rrxnm

Description: The norm of the generalized real Euclidean spaces. (Contributed by Thierry Arnoux, 16-Jun-2019)

Ref Expression
Hypotheses rrxval.r 𝐻 = ( ℝ^ ‘ 𝐼 )
rrxbase.b 𝐵 = ( Base ‘ 𝐻 )
Assertion rrxnm ( 𝐼𝑉 → ( 𝑓𝐵 ↦ ( √ ‘ ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) ) ) = ( norm ‘ 𝐻 ) )

Proof

Step Hyp Ref Expression
1 rrxval.r 𝐻 = ( ℝ^ ‘ 𝐼 )
2 rrxbase.b 𝐵 = ( Base ‘ 𝐻 )
3 recrng fld ∈ *-Ring
4 srngring ( ℝfld ∈ *-Ring → ℝfld ∈ Ring )
5 3 4 ax-mp fld ∈ Ring
6 eqid ( ℝfld freeLMod 𝐼 ) = ( ℝfld freeLMod 𝐼 )
7 6 frlmlmod ( ( ℝfld ∈ Ring ∧ 𝐼𝑉 ) → ( ℝfld freeLMod 𝐼 ) ∈ LMod )
8 5 7 mpan ( 𝐼𝑉 → ( ℝfld freeLMod 𝐼 ) ∈ LMod )
9 lmodgrp ( ( ℝfld freeLMod 𝐼 ) ∈ LMod → ( ℝfld freeLMod 𝐼 ) ∈ Grp )
10 eqid ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) = ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) )
11 eqid ( norm ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) ) = ( norm ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) )
12 eqid ( Base ‘ ( ℝfld freeLMod 𝐼 ) ) = ( Base ‘ ( ℝfld freeLMod 𝐼 ) )
13 eqid ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) = ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) )
14 10 11 12 13 tchnmfval ( ( ℝfld freeLMod 𝐼 ) ∈ Grp → ( norm ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) ) = ( 𝑓 ∈ ( Base ‘ ( ℝfld freeLMod 𝐼 ) ) ↦ ( √ ‘ ( 𝑓 ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) 𝑓 ) ) ) )
15 8 9 14 3syl ( 𝐼𝑉 → ( norm ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) ) = ( 𝑓 ∈ ( Base ‘ ( ℝfld freeLMod 𝐼 ) ) ↦ ( √ ‘ ( 𝑓 ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) 𝑓 ) ) ) )
16 1 rrxval ( 𝐼𝑉𝐻 = ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) )
17 16 fveq2d ( 𝐼𝑉 → ( norm ‘ 𝐻 ) = ( norm ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) ) )
18 16 fveq2d ( 𝐼𝑉 → ( Base ‘ 𝐻 ) = ( Base ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) ) )
19 10 12 tcphbas ( Base ‘ ( ℝfld freeLMod 𝐼 ) ) = ( Base ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) )
20 18 2 19 3eqtr4g ( 𝐼𝑉𝐵 = ( Base ‘ ( ℝfld freeLMod 𝐼 ) ) )
21 1 2 rrxbase ( 𝐼𝑉𝐵 = { 𝑓 ∈ ( ℝ ↑m 𝐼 ) ∣ 𝑓 finSupp 0 } )
22 ssrab2 { 𝑓 ∈ ( ℝ ↑m 𝐼 ) ∣ 𝑓 finSupp 0 } ⊆ ( ℝ ↑m 𝐼 )
23 21 22 eqsstrdi ( 𝐼𝑉𝐵 ⊆ ( ℝ ↑m 𝐼 ) )
24 23 sselda ( ( 𝐼𝑉𝑓𝐵 ) → 𝑓 ∈ ( ℝ ↑m 𝐼 ) )
25 16 fveq2d ( 𝐼𝑉 → ( ·𝑖𝐻 ) = ( ·𝑖 ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) ) )
26 1 2 rrxip ( 𝐼𝑉 → ( ∈ ( ℝ ↑m 𝐼 ) , 𝑔 ∈ ( ℝ ↑m 𝐼 ) ↦ ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑥 ) · ( 𝑔𝑥 ) ) ) ) ) = ( ·𝑖𝐻 ) )
27 10 13 tcphip ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) = ( ·𝑖 ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) )
28 27 a1i ( 𝐼𝑉 → ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) = ( ·𝑖 ‘ ( toℂPreHil ‘ ( ℝfld freeLMod 𝐼 ) ) ) )
29 25 26 28 3eqtr4rd ( 𝐼𝑉 → ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) = ( ∈ ( ℝ ↑m 𝐼 ) , 𝑔 ∈ ( ℝ ↑m 𝐼 ) ↦ ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑥 ) · ( 𝑔𝑥 ) ) ) ) ) )
30 29 adantr ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) → ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) = ( ∈ ( ℝ ↑m 𝐼 ) , 𝑔 ∈ ( ℝ ↑m 𝐼 ) ↦ ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑥 ) · ( 𝑔𝑥 ) ) ) ) ) )
31 simprl ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) → = 𝑓 )
32 31 fveq1d ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) → ( 𝑥 ) = ( 𝑓𝑥 ) )
33 simprr ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) → 𝑔 = 𝑓 )
34 33 fveq1d ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) → ( 𝑔𝑥 ) = ( 𝑓𝑥 ) )
35 32 34 oveq12d ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) → ( ( 𝑥 ) · ( 𝑔𝑥 ) ) = ( ( 𝑓𝑥 ) · ( 𝑓𝑥 ) ) )
36 35 adantr ( ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) ∧ 𝑥𝐼 ) → ( ( 𝑥 ) · ( 𝑔𝑥 ) ) = ( ( 𝑓𝑥 ) · ( 𝑓𝑥 ) ) )
37 elmapi ( 𝑓 ∈ ( ℝ ↑m 𝐼 ) → 𝑓 : 𝐼 ⟶ ℝ )
38 37 adantl ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) → 𝑓 : 𝐼 ⟶ ℝ )
39 38 ffvelrnda ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ 𝑥𝐼 ) → ( 𝑓𝑥 ) ∈ ℝ )
40 39 recnd ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ 𝑥𝐼 ) → ( 𝑓𝑥 ) ∈ ℂ )
41 40 adantlr ( ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) ∧ 𝑥𝐼 ) → ( 𝑓𝑥 ) ∈ ℂ )
42 41 sqvald ( ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) ∧ 𝑥𝐼 ) → ( ( 𝑓𝑥 ) ↑ 2 ) = ( ( 𝑓𝑥 ) · ( 𝑓𝑥 ) ) )
43 36 42 eqtr4d ( ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) ∧ 𝑥𝐼 ) → ( ( 𝑥 ) · ( 𝑔𝑥 ) ) = ( ( 𝑓𝑥 ) ↑ 2 ) )
44 43 mpteq2dva ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) → ( 𝑥𝐼 ↦ ( ( 𝑥 ) · ( 𝑔𝑥 ) ) ) = ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) )
45 44 oveq2d ( ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) ∧ ( = 𝑓𝑔 = 𝑓 ) ) → ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑥 ) · ( 𝑔𝑥 ) ) ) ) = ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) )
46 simpr ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) → 𝑓 ∈ ( ℝ ↑m 𝐼 ) )
47 ovexd ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) → ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) ∈ V )
48 30 45 46 46 47 ovmpod ( ( 𝐼𝑉𝑓 ∈ ( ℝ ↑m 𝐼 ) ) → ( 𝑓 ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) 𝑓 ) = ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) )
49 24 48 syldan ( ( 𝐼𝑉𝑓𝐵 ) → ( 𝑓 ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) 𝑓 ) = ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) )
50 49 eqcomd ( ( 𝐼𝑉𝑓𝐵 ) → ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) = ( 𝑓 ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) 𝑓 ) )
51 50 fveq2d ( ( 𝐼𝑉𝑓𝐵 ) → ( √ ‘ ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) ) = ( √ ‘ ( 𝑓 ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) 𝑓 ) ) )
52 20 51 mpteq12dva ( 𝐼𝑉 → ( 𝑓𝐵 ↦ ( √ ‘ ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) ) ) = ( 𝑓 ∈ ( Base ‘ ( ℝfld freeLMod 𝐼 ) ) ↦ ( √ ‘ ( 𝑓 ( ·𝑖 ‘ ( ℝfld freeLMod 𝐼 ) ) 𝑓 ) ) ) )
53 15 17 52 3eqtr4rd ( 𝐼𝑉 → ( 𝑓𝐵 ↦ ( √ ‘ ( ℝfld Σg ( 𝑥𝐼 ↦ ( ( 𝑓𝑥 ) ↑ 2 ) ) ) ) ) = ( norm ‘ 𝐻 ) )