Metamath Proof Explorer


Theorem odf1

Description: The multiples of an element with infinite order form an infinite cyclic subgroup of G . (Contributed by Mario Carneiro, 14-Jan-2015) (Revised by Mario Carneiro, 23-Sep-2015)

Ref Expression
Hypotheses odf1.1 𝑋 = ( Base ‘ 𝐺 )
odf1.2 𝑂 = ( od ‘ 𝐺 )
odf1.3 · = ( .g𝐺 )
odf1.4 𝐹 = ( 𝑥 ∈ ℤ ↦ ( 𝑥 · 𝐴 ) )
Assertion odf1 ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) → ( ( 𝑂𝐴 ) = 0 ↔ 𝐹 : ℤ –1-1𝑋 ) )

Proof

Step Hyp Ref Expression
1 odf1.1 𝑋 = ( Base ‘ 𝐺 )
2 odf1.2 𝑂 = ( od ‘ 𝐺 )
3 odf1.3 · = ( .g𝐺 )
4 odf1.4 𝐹 = ( 𝑥 ∈ ℤ ↦ ( 𝑥 · 𝐴 ) )
5 1 3 mulgcl ( ( 𝐺 ∈ Grp ∧ 𝑥 ∈ ℤ ∧ 𝐴𝑋 ) → ( 𝑥 · 𝐴 ) ∈ 𝑋 )
6 5 3expa ( ( ( 𝐺 ∈ Grp ∧ 𝑥 ∈ ℤ ) ∧ 𝐴𝑋 ) → ( 𝑥 · 𝐴 ) ∈ 𝑋 )
7 6 an32s ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝑥 ∈ ℤ ) → ( 𝑥 · 𝐴 ) ∈ 𝑋 )
8 7 4 fmptd ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) → 𝐹 : ℤ ⟶ 𝑋 )
9 8 adantr ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) → 𝐹 : ℤ ⟶ 𝑋 )
10 oveq1 ( 𝑥 = 𝑦 → ( 𝑥 · 𝐴 ) = ( 𝑦 · 𝐴 ) )
11 ovex ( 𝑥 · 𝐴 ) ∈ V
12 10 4 11 fvmpt3i ( 𝑦 ∈ ℤ → ( 𝐹𝑦 ) = ( 𝑦 · 𝐴 ) )
13 oveq1 ( 𝑥 = 𝑧 → ( 𝑥 · 𝐴 ) = ( 𝑧 · 𝐴 ) )
14 13 4 11 fvmpt3i ( 𝑧 ∈ ℤ → ( 𝐹𝑧 ) = ( 𝑧 · 𝐴 ) )
15 12 14 eqeqan12d ( ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) → ( ( 𝐹𝑦 ) = ( 𝐹𝑧 ) ↔ ( 𝑦 · 𝐴 ) = ( 𝑧 · 𝐴 ) ) )
16 15 adantl ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝐹𝑦 ) = ( 𝐹𝑧 ) ↔ ( 𝑦 · 𝐴 ) = ( 𝑧 · 𝐴 ) ) )
17 simplr ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( 𝑂𝐴 ) = 0 )
18 17 breq1d ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝑂𝐴 ) ∥ ( 𝑦𝑧 ) ↔ 0 ∥ ( 𝑦𝑧 ) ) )
19 eqid ( 0g𝐺 ) = ( 0g𝐺 )
20 1 2 3 19 odcong ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝑂𝐴 ) ∥ ( 𝑦𝑧 ) ↔ ( 𝑦 · 𝐴 ) = ( 𝑧 · 𝐴 ) ) )
21 20 ad4ant124 ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝑂𝐴 ) ∥ ( 𝑦𝑧 ) ↔ ( 𝑦 · 𝐴 ) = ( 𝑧 · 𝐴 ) ) )
22 zsubcl ( ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) → ( 𝑦𝑧 ) ∈ ℤ )
23 22 adantl ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( 𝑦𝑧 ) ∈ ℤ )
24 0dvds ( ( 𝑦𝑧 ) ∈ ℤ → ( 0 ∥ ( 𝑦𝑧 ) ↔ ( 𝑦𝑧 ) = 0 ) )
25 23 24 syl ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( 0 ∥ ( 𝑦𝑧 ) ↔ ( 𝑦𝑧 ) = 0 ) )
26 18 21 25 3bitr3d ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝑦 · 𝐴 ) = ( 𝑧 · 𝐴 ) ↔ ( 𝑦𝑧 ) = 0 ) )
27 zcn ( 𝑦 ∈ ℤ → 𝑦 ∈ ℂ )
28 zcn ( 𝑧 ∈ ℤ → 𝑧 ∈ ℂ )
29 subeq0 ( ( 𝑦 ∈ ℂ ∧ 𝑧 ∈ ℂ ) → ( ( 𝑦𝑧 ) = 0 ↔ 𝑦 = 𝑧 ) )
30 27 28 29 syl2an ( ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) → ( ( 𝑦𝑧 ) = 0 ↔ 𝑦 = 𝑧 ) )
31 30 adantl ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝑦𝑧 ) = 0 ↔ 𝑦 = 𝑧 ) )
32 16 26 31 3bitrd ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝐹𝑦 ) = ( 𝐹𝑧 ) ↔ 𝑦 = 𝑧 ) )
33 32 biimpd ( ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) ∧ ( 𝑦 ∈ ℤ ∧ 𝑧 ∈ ℤ ) ) → ( ( 𝐹𝑦 ) = ( 𝐹𝑧 ) → 𝑦 = 𝑧 ) )
34 33 ralrimivva ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) → ∀ 𝑦 ∈ ℤ ∀ 𝑧 ∈ ℤ ( ( 𝐹𝑦 ) = ( 𝐹𝑧 ) → 𝑦 = 𝑧 ) )
35 dff13 ( 𝐹 : ℤ –1-1𝑋 ↔ ( 𝐹 : ℤ ⟶ 𝑋 ∧ ∀ 𝑦 ∈ ℤ ∀ 𝑧 ∈ ℤ ( ( 𝐹𝑦 ) = ( 𝐹𝑧 ) → 𝑦 = 𝑧 ) ) )
36 9 34 35 sylanbrc ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ ( 𝑂𝐴 ) = 0 ) → 𝐹 : ℤ –1-1𝑋 )
37 1 2 3 19 odid ( 𝐴𝑋 → ( ( 𝑂𝐴 ) · 𝐴 ) = ( 0g𝐺 ) )
38 1 19 3 mulg0 ( 𝐴𝑋 → ( 0 · 𝐴 ) = ( 0g𝐺 ) )
39 37 38 eqtr4d ( 𝐴𝑋 → ( ( 𝑂𝐴 ) · 𝐴 ) = ( 0 · 𝐴 ) )
40 39 ad2antlr ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( ( 𝑂𝐴 ) · 𝐴 ) = ( 0 · 𝐴 ) )
41 1 2 odcl ( 𝐴𝑋 → ( 𝑂𝐴 ) ∈ ℕ0 )
42 41 ad2antlr ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( 𝑂𝐴 ) ∈ ℕ0 )
43 42 nn0zd ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( 𝑂𝐴 ) ∈ ℤ )
44 oveq1 ( 𝑥 = ( 𝑂𝐴 ) → ( 𝑥 · 𝐴 ) = ( ( 𝑂𝐴 ) · 𝐴 ) )
45 44 4 11 fvmpt3i ( ( 𝑂𝐴 ) ∈ ℤ → ( 𝐹 ‘ ( 𝑂𝐴 ) ) = ( ( 𝑂𝐴 ) · 𝐴 ) )
46 43 45 syl ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( 𝐹 ‘ ( 𝑂𝐴 ) ) = ( ( 𝑂𝐴 ) · 𝐴 ) )
47 0zd ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → 0 ∈ ℤ )
48 oveq1 ( 𝑥 = 0 → ( 𝑥 · 𝐴 ) = ( 0 · 𝐴 ) )
49 48 4 11 fvmpt3i ( 0 ∈ ℤ → ( 𝐹 ‘ 0 ) = ( 0 · 𝐴 ) )
50 47 49 syl ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( 𝐹 ‘ 0 ) = ( 0 · 𝐴 ) )
51 40 46 50 3eqtr4d ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( 𝐹 ‘ ( 𝑂𝐴 ) ) = ( 𝐹 ‘ 0 ) )
52 simpr ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → 𝐹 : ℤ –1-1𝑋 )
53 f1fveq ( ( 𝐹 : ℤ –1-1𝑋 ∧ ( ( 𝑂𝐴 ) ∈ ℤ ∧ 0 ∈ ℤ ) ) → ( ( 𝐹 ‘ ( 𝑂𝐴 ) ) = ( 𝐹 ‘ 0 ) ↔ ( 𝑂𝐴 ) = 0 ) )
54 52 43 47 53 syl12anc ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( ( 𝐹 ‘ ( 𝑂𝐴 ) ) = ( 𝐹 ‘ 0 ) ↔ ( 𝑂𝐴 ) = 0 ) )
55 51 54 mpbid ( ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) ∧ 𝐹 : ℤ –1-1𝑋 ) → ( 𝑂𝐴 ) = 0 )
56 36 55 impbida ( ( 𝐺 ∈ Grp ∧ 𝐴𝑋 ) → ( ( 𝑂𝐴 ) = 0 ↔ 𝐹 : ℤ –1-1𝑋 ) )