Proof of Theorem gch2
Step | Hyp | Ref
| Expression |
1 | | ssv 3950 |
. . 3
⊢ ran
ℵ ⊆ V |
2 | | sseq2 3952 |
. . 3
⊢ (GCH = V
→ (ran ℵ ⊆ GCH ↔ ran ℵ ⊆ V)) |
3 | 1, 2 | mpbiri 257 |
. 2
⊢ (GCH = V
→ ran ℵ ⊆ GCH) |
4 | | cardidm 9710 |
. . . . . . . 8
⊢
(card‘(card‘𝑥)) = (card‘𝑥) |
5 | | iscard3 9842 |
. . . . . . . 8
⊢
((card‘(card‘𝑥)) = (card‘𝑥) ↔ (card‘𝑥) ∈ (ω ∪ ran
ℵ)) |
6 | 4, 5 | mpbi 229 |
. . . . . . 7
⊢
(card‘𝑥)
∈ (ω ∪ ran ℵ) |
7 | | elun 4088 |
. . . . . . 7
⊢
((card‘𝑥)
∈ (ω ∪ ran ℵ) ↔ ((card‘𝑥) ∈ ω ∨ (card‘𝑥) ∈ ran
ℵ)) |
8 | 6, 7 | mpbi 229 |
. . . . . 6
⊢
((card‘𝑥)
∈ ω ∨ (card‘𝑥) ∈ ran ℵ) |
9 | | fingch 10372 |
. . . . . . . . 9
⊢ Fin
⊆ GCH |
10 | | nnfi 8924 |
. . . . . . . . 9
⊢
((card‘𝑥)
∈ ω → (card‘𝑥) ∈ Fin) |
11 | 9, 10 | sselid 3924 |
. . . . . . . 8
⊢
((card‘𝑥)
∈ ω → (card‘𝑥) ∈ GCH) |
12 | 11 | a1i 11 |
. . . . . . 7
⊢ (ran
ℵ ⊆ GCH → ((card‘𝑥) ∈ ω → (card‘𝑥) ∈ GCH)) |
13 | | ssel 3919 |
. . . . . . 7
⊢ (ran
ℵ ⊆ GCH → ((card‘𝑥) ∈ ran ℵ → (card‘𝑥) ∈ GCH)) |
14 | 12, 13 | jaod 856 |
. . . . . 6
⊢ (ran
ℵ ⊆ GCH → (((card‘𝑥) ∈ ω ∨ (card‘𝑥) ∈ ran ℵ) →
(card‘𝑥) ∈
GCH)) |
15 | 8, 14 | mpi 20 |
. . . . 5
⊢ (ran
ℵ ⊆ GCH → (card‘𝑥) ∈ GCH) |
16 | | vex 3435 |
. . . . . . 7
⊢ 𝑥 ∈ V |
17 | | alephon 9818 |
. . . . . . . . . . 11
⊢
(ℵ‘suc 𝑥) ∈ On |
18 | | simpr 485 |
. . . . . . . . . . . 12
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → 𝑥 ∈
On) |
19 | | simpl 483 |
. . . . . . . . . . . . 13
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → ran ℵ ⊆ GCH) |
20 | | alephfnon 9814 |
. . . . . . . . . . . . . 14
⊢ ℵ
Fn On |
21 | | fnfvelrn 6953 |
. . . . . . . . . . . . . 14
⊢ ((ℵ
Fn On ∧ 𝑥 ∈ On)
→ (ℵ‘𝑥)
∈ ran ℵ) |
22 | 20, 18, 21 | sylancr 587 |
. . . . . . . . . . . . 13
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → (ℵ‘𝑥) ∈ ran ℵ) |
23 | 19, 22 | sseldd 3927 |
. . . . . . . . . . . 12
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → (ℵ‘𝑥) ∈ GCH) |
24 | | suceloni 7649 |
. . . . . . . . . . . . . . 15
⊢ (𝑥 ∈ On → suc 𝑥 ∈ On) |
25 | 24 | adantl 482 |
. . . . . . . . . . . . . 14
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → suc 𝑥
∈ On) |
26 | | fnfvelrn 6953 |
. . . . . . . . . . . . . 14
⊢ ((ℵ
Fn On ∧ suc 𝑥 ∈
On) → (ℵ‘suc 𝑥) ∈ ran ℵ) |
27 | 20, 25, 26 | sylancr 587 |
. . . . . . . . . . . . 13
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → (ℵ‘suc 𝑥) ∈ ran ℵ) |
28 | 19, 27 | sseldd 3927 |
. . . . . . . . . . . 12
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → (ℵ‘suc 𝑥) ∈ GCH) |
29 | | gchaleph2 10421 |
. . . . . . . . . . . 12
⊢ ((𝑥 ∈ On ∧
(ℵ‘𝑥) ∈
GCH ∧ (ℵ‘suc 𝑥) ∈ GCH) → (ℵ‘suc 𝑥) ≈ 𝒫
(ℵ‘𝑥)) |
30 | 18, 23, 28, 29 | syl3anc 1370 |
. . . . . . . . . . 11
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → (ℵ‘suc 𝑥) ≈ 𝒫 (ℵ‘𝑥)) |
31 | | isnumi 9697 |
. . . . . . . . . . 11
⊢
(((ℵ‘suc 𝑥) ∈ On ∧ (ℵ‘suc 𝑥) ≈ 𝒫
(ℵ‘𝑥)) →
𝒫 (ℵ‘𝑥)
∈ dom card) |
32 | 17, 30, 31 | sylancr 587 |
. . . . . . . . . 10
⊢ ((ran
ℵ ⊆ GCH ∧ 𝑥
∈ On) → 𝒫 (ℵ‘𝑥) ∈ dom card) |
33 | 32 | ralrimiva 3110 |
. . . . . . . . 9
⊢ (ran
ℵ ⊆ GCH → ∀𝑥 ∈ On 𝒫 (ℵ‘𝑥) ∈ dom
card) |
34 | | dfac12 9898 |
. . . . . . . . 9
⊢
(CHOICE ↔ ∀𝑥 ∈ On 𝒫 (ℵ‘𝑥) ∈ dom
card) |
35 | 33, 34 | sylibr 233 |
. . . . . . . 8
⊢ (ran
ℵ ⊆ GCH → CHOICE) |
36 | | dfac10 9886 |
. . . . . . . 8
⊢
(CHOICE ↔ dom card = V) |
37 | 35, 36 | sylib 217 |
. . . . . . 7
⊢ (ran
ℵ ⊆ GCH → dom card = V) |
38 | 16, 37 | eleqtrrid 2848 |
. . . . . 6
⊢ (ran
ℵ ⊆ GCH → 𝑥 ∈ dom card) |
39 | | cardid2 9704 |
. . . . . 6
⊢ (𝑥 ∈ dom card →
(card‘𝑥) ≈
𝑥) |
40 | | engch 10377 |
. . . . . 6
⊢
((card‘𝑥)
≈ 𝑥 →
((card‘𝑥) ∈ GCH
↔ 𝑥 ∈
GCH)) |
41 | 38, 39, 40 | 3syl 18 |
. . . . 5
⊢ (ran
ℵ ⊆ GCH → ((card‘𝑥) ∈ GCH ↔ 𝑥 ∈ GCH)) |
42 | 15, 41 | mpbid 231 |
. . . 4
⊢ (ran
ℵ ⊆ GCH → 𝑥 ∈ GCH) |
43 | 16 | a1i 11 |
. . . 4
⊢ (ran
ℵ ⊆ GCH → 𝑥 ∈ V) |
44 | 42, 43 | 2thd 264 |
. . 3
⊢ (ran
ℵ ⊆ GCH → (𝑥 ∈ GCH ↔ 𝑥 ∈ V)) |
45 | 44 | eqrdv 2738 |
. 2
⊢ (ran
ℵ ⊆ GCH → GCH = V) |
46 | 3, 45 | impbii 208 |
1
⊢ (GCH = V
↔ ran ℵ ⊆ GCH) |