Theorem tngngp2 23722

Description: A norm turns a group into a normed group iff the generated metric is in fact a metric. (Contributed by Mario Carneiro, 4-Oct-2015.)

Hypotheses

Ref	Expression
tngngp2.t	⊢ 𝑇 = (𝐺 toNrmGrp 𝑁)
tngngp2.x	⊢ 𝑋 = (Base‘𝐺)
tngngp2.d	⊢ 𝐷 = (dist‘𝑇)

Assertion

Ref	Expression
tngngp2	⊢ (𝑁:𝑋⟶ℝ → (𝑇 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))))

Proof of Theorem tngngp2

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		ngpgrp 23661	. . . . 5 ⊢ (𝑇 ∈ NrmGrp → 𝑇 ∈ Grp)
2		tngngp2.x	. . . . . . . 8 ⊢ 𝑋 = (Base‘𝐺)
3	2	fvexi 6770	. . . . . . 7 ⊢ 𝑋 ∈ V
4		reex 10893	. . . . . . 7 ⊢ ℝ ∈ V
5		fex2 7754	. . . . . . 7 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑋 ∈ V ∧ ℝ ∈ V) → 𝑁 ∈ V)
6	3, 4, 5	mp3an23 1451	. . . . . 6 ⊢ (𝑁:𝑋⟶ℝ → 𝑁 ∈ V)
7	2	a1i 11	. . . . . . 7 ⊢ (𝑁 ∈ V → 𝑋 = (Base‘𝐺))
8		tngngp2.t	. . . . . . . 8 ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁)
9	8, 2	tngbas 23704	. . . . . . 7 ⊢ (𝑁 ∈ V → 𝑋 = (Base‘𝑇))
10		eqid 2738	. . . . . . . . 9 ⊢ (+g‘𝐺) = (+g‘𝐺)
11	8, 10	tngplusg 23706	. . . . . . . 8 ⊢ (𝑁 ∈ V → (+g‘𝐺) = (+g‘𝑇))
12	11	oveqdr 7283	. . . . . . 7 ⊢ ((𝑁 ∈ V ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝑥(+g‘𝐺)𝑦) = (𝑥(+g‘𝑇)𝑦))
13	7, 9, 12	grppropd 18509	. . . . . 6 ⊢ (𝑁 ∈ V → (𝐺 ∈ Grp ↔ 𝑇 ∈ Grp))
14	6, 13	syl 17	. . . . 5 ⊢ (𝑁:𝑋⟶ℝ → (𝐺 ∈ Grp ↔ 𝑇 ∈ Grp))
15	1, 14	syl5ibr 245	. . . 4 ⊢ (𝑁:𝑋⟶ℝ → (𝑇 ∈ NrmGrp → 𝐺 ∈ Grp))
16	15	imp 406	. . 3 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝐺 ∈ Grp)
17		ngpms 23662	. . . . . 6 ⊢ (𝑇 ∈ NrmGrp → 𝑇 ∈ MetSp)
18	17	adantl 481	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝑇 ∈ MetSp)
19		eqid 2738	. . . . . 6 ⊢ (Base‘𝑇) = (Base‘𝑇)
20		tngngp2.d	. . . . . 6 ⊢ 𝐷 = (dist‘𝑇)
21	19, 20	msmet2 23521	. . . . 5 ⊢ (𝑇 ∈ MetSp → (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))) ∈ (Met‘(Base‘𝑇)))
22	18, 21	syl 17	. . . 4 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))) ∈ (Met‘(Base‘𝑇)))
23		eqid 2738	. . . . . . . . . 10 ⊢ (-g‘𝐺) = (-g‘𝐺)
24	2, 23	grpsubf 18569	. . . . . . . . 9 ⊢ (𝐺 ∈ Grp → (-g‘𝐺):(𝑋 × 𝑋)⟶𝑋)
25	16, 24	syl 17	. . . . . . . 8 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (-g‘𝐺):(𝑋 × 𝑋)⟶𝑋)
26		fco 6608	. . . . . . . 8 ⊢ ((𝑁:𝑋⟶ℝ ∧ (-g‘𝐺):(𝑋 × 𝑋)⟶𝑋) → (𝑁 ∘ (-g‘𝐺)):(𝑋 × 𝑋)⟶ℝ)
27	25, 26	syldan 590	. . . . . . 7 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝑁 ∘ (-g‘𝐺)):(𝑋 × 𝑋)⟶ℝ)
28	6	adantr 480	. . . . . . . . . 10 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝑁 ∈ V)
29	8, 23	tngds 23717	. . . . . . . . . 10 ⊢ (𝑁 ∈ V → (𝑁 ∘ (-g‘𝐺)) = (dist‘𝑇))
30	28, 29	syl 17	. . . . . . . . 9 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝑁 ∘ (-g‘𝐺)) = (dist‘𝑇))
31	20, 30	eqtr4id 2798	. . . . . . . 8 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝐷 = (𝑁 ∘ (-g‘𝐺)))
32	31	feq1d 6569	. . . . . . 7 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝐷:(𝑋 × 𝑋)⟶ℝ ↔ (𝑁 ∘ (-g‘𝐺)):(𝑋 × 𝑋)⟶ℝ))
33	27, 32	mpbird 256	. . . . . 6 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝐷:(𝑋 × 𝑋)⟶ℝ)
34		ffn 6584	. . . . . 6 ⊢ (𝐷:(𝑋 × 𝑋)⟶ℝ → 𝐷 Fn (𝑋 × 𝑋))
35		fnresdm 6535	. . . . . 6 ⊢ (𝐷 Fn (𝑋 × 𝑋) → (𝐷 ↾ (𝑋 × 𝑋)) = 𝐷)
36	33, 34, 35	3syl 18	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝐷 ↾ (𝑋 × 𝑋)) = 𝐷)
37	28, 9	syl 17	. . . . . . 7 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝑋 = (Base‘𝑇))
38	37	sqxpeqd 5612	. . . . . 6 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝑋 × 𝑋) = ((Base‘𝑇) × (Base‘𝑇)))
39	38	reseq2d 5880	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝐷 ↾ (𝑋 × 𝑋)) = (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))))
40	36, 39	eqtr3d 2780	. . . 4 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝐷 = (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))))
41	37	fveq2d 6760	. . . 4 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (Met‘𝑋) = (Met‘(Base‘𝑇)))
42	22, 40, 41	3eltr4d 2854	. . 3 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → 𝐷 ∈ (Met‘𝑋))
43	16, 42	jca 511	. 2 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝑇 ∈ NrmGrp) → (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋)))
44	14	biimpa 476	. . . 4 ⊢ ((𝑁:𝑋⟶ℝ ∧ 𝐺 ∈ Grp) → 𝑇 ∈ Grp)
45	44	adantrr 713	. . 3 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝑇 ∈ Grp)
46		simprr 769	. . . . . . . 8 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝐷 ∈ (Met‘𝑋))
47	6	adantr 480	. . . . . . . . . 10 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝑁 ∈ V)
48	47, 9	syl 17	. . . . . . . . 9 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝑋 = (Base‘𝑇))
49	48	fveq2d 6760	. . . . . . . 8 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (Met‘𝑋) = (Met‘(Base‘𝑇)))
50	46, 49	eleqtrd 2841	. . . . . . 7 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝐷 ∈ (Met‘(Base‘𝑇)))
51		metf 23391	. . . . . . 7 ⊢ (𝐷 ∈ (Met‘(Base‘𝑇)) → 𝐷:((Base‘𝑇) × (Base‘𝑇))⟶ℝ)
52	50, 51	syl 17	. . . . . 6 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝐷:((Base‘𝑇) × (Base‘𝑇))⟶ℝ)
53		ffn 6584	. . . . . 6 ⊢ (𝐷:((Base‘𝑇) × (Base‘𝑇))⟶ℝ → 𝐷 Fn ((Base‘𝑇) × (Base‘𝑇)))
54		fnresdm 6535	. . . . . 6 ⊢ (𝐷 Fn ((Base‘𝑇) × (Base‘𝑇)) → (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))) = 𝐷)
55	52, 53, 54	3syl 18	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))) = 𝐷)
56	55, 50	eqeltrd 2839	. . . 4 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))) ∈ (Met‘(Base‘𝑇)))
57	55	fveq2d 6760	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (MetOpen‘(𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇)))) = (MetOpen‘𝐷))
58		simprl 767	. . . . . 6 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝐺 ∈ Grp)
59		eqid 2738	. . . . . . 7 ⊢ (MetOpen‘𝐷) = (MetOpen‘𝐷)
60	8, 20, 59	tngtopn 23720	. . . . . 6 ⊢ ((𝐺 ∈ Grp ∧ 𝑁 ∈ V) → (MetOpen‘𝐷) = (TopOpen‘𝑇))
61	58, 47, 60	syl2anc 583	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (MetOpen‘𝐷) = (TopOpen‘𝑇))
62	57, 61	eqtr2d 2779	. . . 4 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (TopOpen‘𝑇) = (MetOpen‘(𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇)))))
63		eqid 2738	. . . . 5 ⊢ (TopOpen‘𝑇) = (TopOpen‘𝑇)
64	20	reseq1i 5876	. . . . 5 ⊢ (𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))) = ((dist‘𝑇) ↾ ((Base‘𝑇) × (Base‘𝑇)))
65	63, 19, 64	isms2 23511	. . . 4 ⊢ (𝑇 ∈ MetSp ↔ ((𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))) ∈ (Met‘(Base‘𝑇)) ∧ (TopOpen‘𝑇) = (MetOpen‘(𝐷 ↾ ((Base‘𝑇) × (Base‘𝑇))))))
66	56, 62, 65	sylanbrc 582	. . 3 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝑇 ∈ MetSp)
67		simpl 482	. . . . . . 7 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝑁:𝑋⟶ℝ)
68	8, 2, 4	tngnm 23721	. . . . . . 7 ⊢ ((𝐺 ∈ Grp ∧ 𝑁:𝑋⟶ℝ) → 𝑁 = (norm‘𝑇))
69	58, 67, 68	syl2anc 583	. . . . . 6 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝑁 = (norm‘𝑇))
70	7, 9	eqtr3d 2780	. . . . . . . 8 ⊢ (𝑁 ∈ V → (Base‘𝐺) = (Base‘𝑇))
71	70, 11	grpsubpropd 18595	. . . . . . 7 ⊢ (𝑁 ∈ V → (-g‘𝐺) = (-g‘𝑇))
72	47, 71	syl 17	. . . . . 6 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (-g‘𝐺) = (-g‘𝑇))
73	69, 72	coeq12d 5762	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (𝑁 ∘ (-g‘𝐺)) = ((norm‘𝑇) ∘ (-g‘𝑇)))
74	47, 29	syl 17	. . . . 5 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → (𝑁 ∘ (-g‘𝐺)) = (dist‘𝑇))
75	73, 74	eqtr3d 2780	. . . 4 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → ((norm‘𝑇) ∘ (-g‘𝑇)) = (dist‘𝑇))
76		eqimss 3973	. . . 4 ⊢ (((norm‘𝑇) ∘ (-g‘𝑇)) = (dist‘𝑇) → ((norm‘𝑇) ∘ (-g‘𝑇)) ⊆ (dist‘𝑇))
77	75, 76	syl 17	. . 3 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → ((norm‘𝑇) ∘ (-g‘𝑇)) ⊆ (dist‘𝑇))
78		eqid 2738	. . . 4 ⊢ (norm‘𝑇) = (norm‘𝑇)
79		eqid 2738	. . . 4 ⊢ (-g‘𝑇) = (-g‘𝑇)
80		eqid 2738	. . . 4 ⊢ (dist‘𝑇) = (dist‘𝑇)
81	78, 79, 80	isngp 23658	. . 3 ⊢ (𝑇 ∈ NrmGrp ↔ (𝑇 ∈ Grp ∧ 𝑇 ∈ MetSp ∧ ((norm‘𝑇) ∘ (-g‘𝑇)) ⊆ (dist‘𝑇)))
82	45, 66, 77, 81	syl3anbrc 1341	. 2 ⊢ ((𝑁:𝑋⟶ℝ ∧ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))) → 𝑇 ∈ NrmGrp)
83	43, 82	impbida 797	1 ⊢ (𝑁:𝑋⟶ℝ → (𝑇 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋))))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 395   = wceq 1539   ∈ wcel 2108  Vcvv 3422   ⊆ wss 3883   × cxp 5578   ↾ cres 5582   ∘ ccom 5584   Fn wfn 6413  ⟶wf 6414  ‘cfv 6418  (class class class)co 7255  ℝcr 10801  Basecbs 16840  +_gcplusg 16888  distcds 16897  TopOpenctopn 17049  Grpcgrp 18492  -_gcsg 18494  Metcmet 20496  MetOpencmopn 20500  MetSpcms 23379  normcnm 23638  NrmGrpcngp 23639   toNrmGrp ctng 23640

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1799  ax-4 1813  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2110  ax-9 2118  ax-10 2139  ax-11 2156  ax-12 2173  ax-ext 2709  ax-rep 5205  ax-sep 5218  ax-nul 5225  ax-pow 5283  ax-pr 5347  ax-un 7566  ax-cnex 10858  ax-resscn 10859  ax-1cn 10860  ax-icn 10861  ax-addcl 10862  ax-addrcl 10863  ax-mulcl 10864  ax-mulrcl 10865  ax-mulcom 10866  ax-addass 10867  ax-mulass 10868  ax-distr 10869  ax-i2m1 10870  ax-1ne0 10871  ax-1rid 10872  ax-rnegex 10873  ax-rrecex 10874  ax-cnre 10875  ax-pre-lttri 10876  ax-pre-lttrn 10877  ax-pre-ltadd 10878  ax-pre-mulgt0 10879  ax-pre-sup 10880

This theorem depends on definitions:  df-bi 206  df-an 396  df-or 844  df-3or 1086  df-3an 1087  df-tru 1542  df-fal 1552  df-ex 1784  df-nf 1788  df-sb 2069  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2817  df-nfc 2888  df-ne 2943  df-nel 3049  df-ral 3068  df-rex 3069  df-reu 3070  df-rmo 3071  df-rab 3072  df-v 3424  df-sbc 3712  df-csb 3829  df-dif 3886  df-un 3888  df-in 3890  df-ss 3900  df-pss 3902  df-nul 4254  df-if 4457  df-pw 4532  df-sn 4559  df-pr 4561  df-tp 4563  df-op 4565  df-uni 4837  df-iun 4923  df-br 5071  df-opab 5133  df-mpt 5154  df-tr 5188  df-id 5480  df-eprel 5486  df-po 5494  df-so 5495  df-fr 5535  df-we 5537  df-xp 5586  df-rel 5587  df-cnv 5588  df-co 5589  df-dm 5590  df-rn 5591  df-res 5592  df-ima 5593  df-pred 6191  df-ord 6254  df-on 6255  df-lim 6256  df-suc 6257  df-iota 6376  df-fun 6420  df-fn 6421  df-f 6422  df-f1 6423  df-fo 6424  df-f1o 6425  df-fv 6426  df-riota 7212  df-ov 7258  df-oprab 7259  df-mpo 7260  df-om 7688  df-1st 7804  df-2nd 7805  df-frecs 8068  df-wrecs 8099  df-recs 8173  df-rdg 8212  df-er 8456  df-map 8575  df-en 8692  df-dom 8693  df-sdom 8694  df-sup 9131  df-inf 9132  df-pnf 10942  df-mnf 10943  df-xr 10944  df-ltxr 10945  df-le 10946  df-sub 11137  df-neg 11138  df-div 11563  df-nn 11904  df-2 11966  df-3 11967  df-4 11968  df-5 11969  df-6 11970  df-7 11971  df-8 11972  df-9 11973  df-n0 12164  df-z 12250  df-dec 12367  df-uz 12512  df-q 12618  df-rp 12660  df-xneg 12777  df-xadd 12778  df-xmul 12779  df-sets 16793  df-slot 16811  df-ndx 16823  df-base 16841  df-plusg 16901  df-tset 16907  df-ds 16910  df-rest 17050  df-topn 17051  df-0g 17069  df-topgen 17071  df-mgm 18241  df-sgrp 18290  df-mnd 18301  df-grp 18495  df-minusg 18496  df-sbg 18497  df-psmet 20502  df-xmet 20503  df-met 20504  df-bl 20505  df-mopn 20506  df-top 21951  df-topon 21968  df-topsp 21990  df-bases 22004  df-xms 23381  df-ms 23382  df-nm 23644  df-ngp 23645  df-tng 23646

This theorem is referenced by:  tngngpd  23723  tngngp  23724  nrmtngnrm  23728  tngngpim  23729  tngnrg  23744