Theorem alephfp 10050

Description: The aleph function has a fixed point. Similar to Proposition 11.18 of [TakeutiZaring] p. 104, except that we construct an actual example of a fixed point rather than just showing its existence. See alephfp2 10051 for an abbreviated version just showing existence. (Contributed by NM, 6-Nov-2004.) (Proof shortened by Mario Carneiro, 15-May-2015.)

Hypothesis

Ref	Expression
alephfplem.1	⊢ 𝐻 = (rec(ℵ, ω) ↾ ω)

Assertion

Ref	Expression
alephfp	⊢ (ℵ‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω)

Proof of Theorem alephfp

Dummy variables 𝑧 𝑣 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		alephfplem.1	. . 3 ⊢ 𝐻 = (rec(ℵ, ω) ↾ ω)
2	1	alephfplem4 10049	. 2 ⊢ ∪ (𝐻 “ ω) ∈ ran ℵ
3		isinfcard 10034	. . 3 ⊢ ((ω ⊆ ∪ (𝐻 “ ω) ∧ (card‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω)) ↔ ∪ (𝐻 “ ω) ∈ ran ℵ)
4		cardalephex 10032	. . . 4 ⊢ (ω ⊆ ∪ (𝐻 “ ω) → ((card‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω) ↔ ∃𝑧 ∈ On ∪ (𝐻 “ ω) = (ℵ‘𝑧)))
5	4	biimpa 479	. . 3 ⊢ ((ω ⊆ ∪ (𝐻 “ ω) ∧ (card‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω)) → ∃𝑧 ∈ On ∪ (𝐻 “ ω) = (ℵ‘𝑧))
6	3, 5	sylbir 237	. 2 ⊢ (∪ (𝐻 “ ω) ∈ ran ℵ → ∃𝑧 ∈ On ∪ (𝐻 “ ω) = (ℵ‘𝑧))
7		alephle 10030	. . . . . . . . 9 ⊢ (𝑧 ∈ On → 𝑧 ⊆ (ℵ‘𝑧))
8		alephon 10011	. . . . . . . . . . 11 ⊢ (ℵ‘𝑧) ∈ On
9	8	onirri 6445	. . . . . . . . . 10 ⊢ ¬ (ℵ‘𝑧) ∈ (ℵ‘𝑧)
10		frfnom 8390	. . . . . . . . . . . . . 14 ⊢ (rec(ℵ, ω) ↾ ω) Fn ω
11	1	fneq1i 6603	. . . . . . . . . . . . . 14 ⊢ (𝐻 Fn ω ↔ (rec(ℵ, ω) ↾ ω) Fn ω)
12	10, 11	mpbir 233	. . . . . . . . . . . . 13 ⊢ 𝐻 Fn ω
13		fnfun 6606	. . . . . . . . . . . . 13 ⊢ (𝐻 Fn ω → Fun 𝐻)
14		eluniima 7219	. . . . . . . . . . . . 13 ⊢ (Fun 𝐻 → (𝑧 ∈ ∪ (𝐻 “ ω) ↔ ∃𝑣 ∈ ω 𝑧 ∈ (𝐻‘𝑣)))
15	12, 13, 14	mp2b 10	. . . . . . . . . . . 12 ⊢ (𝑧 ∈ ∪ (𝐻 “ ω) ↔ ∃𝑣 ∈ ω 𝑧 ∈ (𝐻‘𝑣))
16		alephsson 10042	. . . . . . . . . . . . . . . 16 ⊢ ran ℵ ⊆ On
17	1	alephfplem3 10048	. . . . . . . . . . . . . . . 16 ⊢ (𝑣 ∈ ω → (𝐻‘𝑣) ∈ ran ℵ)
18	16, 17	sselid 3925	. . . . . . . . . . . . . . 15 ⊢ (𝑣 ∈ ω → (𝐻‘𝑣) ∈ On)
19		alephord2i 10019	. . . . . . . . . . . . . . 15 ⊢ ((𝐻‘𝑣) ∈ On → (𝑧 ∈ (𝐻‘𝑣) → (ℵ‘𝑧) ∈ (ℵ‘(𝐻‘𝑣))))
20	18, 19	syl 17	. . . . . . . . . . . . . 14 ⊢ (𝑣 ∈ ω → (𝑧 ∈ (𝐻‘𝑣) → (ℵ‘𝑧) ∈ (ℵ‘(𝐻‘𝑣))))
21	1	alephfplem2 10047	. . . . . . . . . . . . . . . . 17 ⊢ (𝑣 ∈ ω → (𝐻‘suc 𝑣) = (ℵ‘(𝐻‘𝑣)))
22		peano2 7855	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑣 ∈ ω → suc 𝑣 ∈ ω)
23		fnfvelrn 7046	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝐻 Fn ω ∧ suc 𝑣 ∈ ω) → (𝐻‘suc 𝑣) ∈ ran 𝐻)
24	12, 23	mpan 698	. . . . . . . . . . . . . . . . . . 19 ⊢ (suc 𝑣 ∈ ω → (𝐻‘suc 𝑣) ∈ ran 𝐻)
25		fnima 6636	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝐻 Fn ω → (𝐻 “ ω) = ran 𝐻)
26	12, 25	ax-mp 5	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝐻 “ ω) = ran 𝐻
27	24, 26	eleqtrrdi 2863	. . . . . . . . . . . . . . . . . 18 ⊢ (suc 𝑣 ∈ ω → (𝐻‘suc 𝑣) ∈ (𝐻 “ ω))
28	22, 27	syl 17	. . . . . . . . . . . . . . . . 17 ⊢ (𝑣 ∈ ω → (𝐻‘suc 𝑣) ∈ (𝐻 “ ω))
29	21, 28	eqeltrrd 2853	. . . . . . . . . . . . . . . 16 ⊢ (𝑣 ∈ ω → (ℵ‘(𝐻‘𝑣)) ∈ (𝐻 “ ω))
30		elssuni 4887	. . . . . . . . . . . . . . . 16 ⊢ ((ℵ‘(𝐻‘𝑣)) ∈ (𝐻 “ ω) → (ℵ‘(𝐻‘𝑣)) ⊆ ∪ (𝐻 “ ω))
31	29, 30	syl 17	. . . . . . . . . . . . . . 15 ⊢ (𝑣 ∈ ω → (ℵ‘(𝐻‘𝑣)) ⊆ ∪ (𝐻 “ ω))
32	31	sseld 3926	. . . . . . . . . . . . . 14 ⊢ (𝑣 ∈ ω → ((ℵ‘𝑧) ∈ (ℵ‘(𝐻‘𝑣)) → (ℵ‘𝑧) ∈ ∪ (𝐻 “ ω)))
33	20, 32	syld 47	. . . . . . . . . . . . 13 ⊢ (𝑣 ∈ ω → (𝑧 ∈ (𝐻‘𝑣) → (ℵ‘𝑧) ∈ ∪ (𝐻 “ ω)))
34	33	rexlimiv 3146	. . . . . . . . . . . 12 ⊢ (∃𝑣 ∈ ω 𝑧 ∈ (𝐻‘𝑣) → (ℵ‘𝑧) ∈ ∪ (𝐻 “ ω))
35	15, 34	sylbi 219	. . . . . . . . . . 11 ⊢ (𝑧 ∈ ∪ (𝐻 “ ω) → (ℵ‘𝑧) ∈ ∪ (𝐻 “ ω))
36		eleq2 2841	. . . . . . . . . . . 12 ⊢ (∪ (𝐻 “ ω) = (ℵ‘𝑧) → (𝑧 ∈ ∪ (𝐻 “ ω) ↔ 𝑧 ∈ (ℵ‘𝑧)))
37		eleq2 2841	. . . . . . . . . . . 12 ⊢ (∪ (𝐻 “ ω) = (ℵ‘𝑧) → ((ℵ‘𝑧) ∈ ∪ (𝐻 “ ω) ↔ (ℵ‘𝑧) ∈ (ℵ‘𝑧)))
38	36, 37	imbi12d 346	. . . . . . . . . . 11 ⊢ (∪ (𝐻 “ ω) = (ℵ‘𝑧) → ((𝑧 ∈ ∪ (𝐻 “ ω) → (ℵ‘𝑧) ∈ ∪ (𝐻 “ ω)) ↔ (𝑧 ∈ (ℵ‘𝑧) → (ℵ‘𝑧) ∈ (ℵ‘𝑧))))
39	35, 38	mpbii 235	. . . . . . . . . 10 ⊢ (∪ (𝐻 “ ω) = (ℵ‘𝑧) → (𝑧 ∈ (ℵ‘𝑧) → (ℵ‘𝑧) ∈ (ℵ‘𝑧)))
40	9, 39	mtoi 201	. . . . . . . . 9 ⊢ (∪ (𝐻 “ ω) = (ℵ‘𝑧) → ¬ 𝑧 ∈ (ℵ‘𝑧))
41	7, 40	anim12i 621	. . . . . . . 8 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → (𝑧 ⊆ (ℵ‘𝑧) ∧ ¬ 𝑧 ∈ (ℵ‘𝑧)))
42		eloni 6341	. . . . . . . . . 10 ⊢ (𝑧 ∈ On → Ord 𝑧)
43	8	onordi 6444	. . . . . . . . . 10 ⊢ Ord (ℵ‘𝑧)
44		ordtri4 6368	. . . . . . . . . 10 ⊢ ((Ord 𝑧 ∧ Ord (ℵ‘𝑧)) → (𝑧 = (ℵ‘𝑧) ↔ (𝑧 ⊆ (ℵ‘𝑧) ∧ ¬ 𝑧 ∈ (ℵ‘𝑧))))
45	42, 43, 44	sylancl 594	. . . . . . . . 9 ⊢ (𝑧 ∈ On → (𝑧 = (ℵ‘𝑧) ↔ (𝑧 ⊆ (ℵ‘𝑧) ∧ ¬ 𝑧 ∈ (ℵ‘𝑧))))
46	45	adantr 483	. . . . . . . 8 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → (𝑧 = (ℵ‘𝑧) ↔ (𝑧 ⊆ (ℵ‘𝑧) ∧ ¬ 𝑧 ∈ (ℵ‘𝑧))))
47	41, 46	mpbird 259	. . . . . . 7 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → 𝑧 = (ℵ‘𝑧))
48		eqeq2 2764	. . . . . . . 8 ⊢ (∪ (𝐻 “ ω) = (ℵ‘𝑧) → (𝑧 = ∪ (𝐻 “ ω) ↔ 𝑧 = (ℵ‘𝑧)))
49	48	adantl 484	. . . . . . 7 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → (𝑧 = ∪ (𝐻 “ ω) ↔ 𝑧 = (ℵ‘𝑧)))
50	47, 49	mpbird 259	. . . . . 6 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → 𝑧 = ∪ (𝐻 “ ω))
51	50	eqcomd 2758	. . . . 5 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → ∪ (𝐻 “ ω) = 𝑧)
52	51	fveq2d 6856	. . . 4 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → (ℵ‘∪ (𝐻 “ ω)) = (ℵ‘𝑧))
53		eqeq2 2764	. . . . 5 ⊢ (∪ (𝐻 “ ω) = (ℵ‘𝑧) → ((ℵ‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω) ↔ (ℵ‘∪ (𝐻 “ ω)) = (ℵ‘𝑧)))
54	53	adantl 484	. . . 4 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → ((ℵ‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω) ↔ (ℵ‘∪ (𝐻 “ ω)) = (ℵ‘𝑧)))
55	52, 54	mpbird 259	. . 3 ⊢ ((𝑧 ∈ On ∧ ∪ (𝐻 “ ω) = (ℵ‘𝑧)) → (ℵ‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω))
56	55	rexlimiva 3145	. 2 ⊢ (∃𝑧 ∈ On ∪ (𝐻 “ ω) = (ℵ‘𝑧) → (ℵ‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω))
57	2, 6, 56	mp2b 10	1 ⊢ (ℵ‘∪ (𝐻 “ ω)) = ∪ (𝐻 “ ω)

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 208   ∧ wa 398   = wceq 1550   ∈ wcel 2132  ∃wrex 3076   ⊆ wss 3895  ∪ cuni 4855  ran crn 5637   ↾ cres 5638   “ cima 5639  Ord word 6330  Oncon0 6331  suc csuc 6333  Fun wfun 6500   Fn wfn 6501  ‘cfv 6506  ωcom 7831  reccrdg 8364  cardccrd 9879  ℵcale 9880

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1805  ax-4 1819  ax-5 1920  ax-6 1977  ax-7 2018  ax-8 2134  ax-9 2142  ax-10 2165  ax-11 2181  ax-12 2202  ax-ext 2724  ax-rep 5217  ax-sep 5236  ax-nul 5246  ax-pow 5312  ax-pr 5380  ax-un 7703  ax-inf2 9582

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 857  df-3or 1096  df-3an 1097  df-tru 1553  df-fal 1563  df-ex 1790  df-nf 1794  df-sb 2081  df-mo 2556  df-eu 2586  df-clab 2731  df-cleq 2744  df-clel 2827  df-nfc 2901  df-ne 2948  df-ral 3067  df-rex 3077  df-rmo 3357  df-reu 3358  df-rab 3405  df-v 3446  df-sbc 3736  df-csb 3844  df-dif 3898  df-un 3900  df-in 3902  df-ss 3912  df-pss 3915  df-nul 4277  df-if 4471  df-pw 4547  df-sn 4573  df-pr 4575  df-op 4579  df-uni 4856  df-int 4896  df-iun 4941  df-br 5091  df-opab 5153  df-mpt 5172  df-tr 5198  df-id 5531  df-eprel 5536  df-po 5544  df-so 5545  df-fr 5589  df-se 5590  df-we 5591  df-xp 5642  df-rel 5643  df-cnv 5644  df-co 5645  df-dm 5646  df-rn 5647  df-res 5648  df-ima 5649  df-pred 6273  df-ord 6334  df-on 6335  df-lim 6336  df-suc 6337  df-iota 6462  df-fun 6508  df-fn 6509  df-f 6510  df-f1 6511  df-fo 6512  df-f1o 6513  df-fv 6514  df-isom 6515  df-riota 7338  df-ov 7384  df-om 7832  df-2nd 7956  df-frecs 8246  df-wrecs 8277  df-recs 8326  df-rdg 8365  df-1o 8421  df-er 8662  df-en 8913  df-dom 8914  df-sdom 8915  df-fin 8916  df-oi 9444  df-har 9491  df-card 9883  df-aleph 9884

This theorem is referenced by:  alephfp2  10051