Theorem alephdom 8787

Description: Relationship between inclusion of ordinal numbers and dominance of infinite initial ordinals. (Contributed by Jeff Hankins, 23-Oct-2009.)

Assertion

Ref	Expression
alephdom	⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 ⊆ 𝐵 ↔ (ℵ‘𝐴) ≼ (ℵ‘𝐵)))

Proof of Theorem alephdom

Step	Hyp	Ref	Expression
1		onsseleq 5682	. . 3 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 ⊆ 𝐵 ↔ (𝐴 ∈ 𝐵 ∨ 𝐴 = 𝐵)))
2		alephord 8781	. . . . 5 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 ∈ 𝐵 ↔ (ℵ‘𝐴) ≺ (ℵ‘𝐵)))
3		sdomdom 7869	. . . . 5 ⊢ ((ℵ‘𝐴) ≺ (ℵ‘𝐵) → (ℵ‘𝐴) ≼ (ℵ‘𝐵))
4	2, 3	syl6bi 242	. . . 4 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 ∈ 𝐵 → (ℵ‘𝐴) ≼ (ℵ‘𝐵)))
5		fvex 6113	. . . . . . 7 ⊢ (ℵ‘𝐴) ∈ V
6		fveq2 6103	. . . . . . 7 ⊢ (𝐴 = 𝐵 → (ℵ‘𝐴) = (ℵ‘𝐵))
7		eqeng 7875	. . . . . . 7 ⊢ ((ℵ‘𝐴) ∈ V → ((ℵ‘𝐴) = (ℵ‘𝐵) → (ℵ‘𝐴) ≈ (ℵ‘𝐵)))
8	5, 6, 7	mpsyl 66	. . . . . 6 ⊢ (𝐴 = 𝐵 → (ℵ‘𝐴) ≈ (ℵ‘𝐵))
9	8	a1i 11	. . . . 5 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 = 𝐵 → (ℵ‘𝐴) ≈ (ℵ‘𝐵)))
10		endom 7868	. . . . 5 ⊢ ((ℵ‘𝐴) ≈ (ℵ‘𝐵) → (ℵ‘𝐴) ≼ (ℵ‘𝐵))
11	9, 10	syl6 34	. . . 4 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 = 𝐵 → (ℵ‘𝐴) ≼ (ℵ‘𝐵)))
12	4, 11	jaod 394	. . 3 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → ((𝐴 ∈ 𝐵 ∨ 𝐴 = 𝐵) → (ℵ‘𝐴) ≼ (ℵ‘𝐵)))
13	1, 12	sylbid 229	. 2 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 ⊆ 𝐵 → (ℵ‘𝐴) ≼ (ℵ‘𝐵)))
14		eloni 5650	. . . . . 6 ⊢ (𝐵 ∈ On → Ord 𝐵)
15		eloni 5650	. . . . . 6 ⊢ (𝐴 ∈ On → Ord 𝐴)
16		ordtri2or 5739	. . . . . 6 ⊢ ((Ord 𝐵 ∧ Ord 𝐴) → (𝐵 ∈ 𝐴 ∨ 𝐴 ⊆ 𝐵))
17	14, 15, 16	syl2anr 494	. . . . 5 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐵 ∈ 𝐴 ∨ 𝐴 ⊆ 𝐵))
18	17	ord 391	. . . 4 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (¬ 𝐵 ∈ 𝐴 → 𝐴 ⊆ 𝐵))
19	18	con1d 138	. . 3 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (¬ 𝐴 ⊆ 𝐵 → 𝐵 ∈ 𝐴))
20		alephord 8781	. . . . 5 ⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ On) → (𝐵 ∈ 𝐴 ↔ (ℵ‘𝐵) ≺ (ℵ‘𝐴)))
21	20	ancoms 468	. . . 4 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐵 ∈ 𝐴 ↔ (ℵ‘𝐵) ≺ (ℵ‘𝐴)))
22		sdomnen 7870	. . . . 5 ⊢ ((ℵ‘𝐵) ≺ (ℵ‘𝐴) → ¬ (ℵ‘𝐵) ≈ (ℵ‘𝐴))
23		sdomdom 7869	. . . . . 6 ⊢ ((ℵ‘𝐵) ≺ (ℵ‘𝐴) → (ℵ‘𝐵) ≼ (ℵ‘𝐴))
24		sbth 7965	. . . . . . 7 ⊢ (((ℵ‘𝐵) ≼ (ℵ‘𝐴) ∧ (ℵ‘𝐴) ≼ (ℵ‘𝐵)) → (ℵ‘𝐵) ≈ (ℵ‘𝐴))
25	24	ex 449	. . . . . 6 ⊢ ((ℵ‘𝐵) ≼ (ℵ‘𝐴) → ((ℵ‘𝐴) ≼ (ℵ‘𝐵) → (ℵ‘𝐵) ≈ (ℵ‘𝐴)))
26	23, 25	syl 17	. . . . 5 ⊢ ((ℵ‘𝐵) ≺ (ℵ‘𝐴) → ((ℵ‘𝐴) ≼ (ℵ‘𝐵) → (ℵ‘𝐵) ≈ (ℵ‘𝐴)))
27	22, 26	mtod 188	. . . 4 ⊢ ((ℵ‘𝐵) ≺ (ℵ‘𝐴) → ¬ (ℵ‘𝐴) ≼ (ℵ‘𝐵))
28	21, 27	syl6bi 242	. . 3 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐵 ∈ 𝐴 → ¬ (ℵ‘𝐴) ≼ (ℵ‘𝐵)))
29	19, 28	syld 46	. 2 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (¬ 𝐴 ⊆ 𝐵 → ¬ (ℵ‘𝐴) ≼ (ℵ‘𝐵)))
30	13, 29	impcon4bid 216	1 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On) → (𝐴 ⊆ 𝐵 ↔ (ℵ‘𝐴) ≼ (ℵ‘𝐵)))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 195   ∨ wo 382   ∧ wa 383   = wceq 1475   ∈ wcel 1977  Vcvv 3173   ⊆ wss 3540   class class class wbr 4583  Ord word 5639  Oncon0 5640  ‘cfv 5804   ≈ cen 7838   ≼ cdom 7839   ≺ csdm 7840  ℵcale 8645

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-rep 4699  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847  ax-inf2 8421

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3or 1032  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-ral 2901  df-rex 2902  df-reu 2903  df-rmo 2904  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-pss 3556  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-tp 4130  df-op 4132  df-uni 4373  df-int 4411  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-tr 4681  df-eprel 4949  df-id 4953  df-po 4959  df-so 4960  df-fr 4997  df-se 4998  df-we 4999  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-pred 5597  df-ord 5643  df-on 5644  df-lim 5645  df-suc 5646  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-isom 5813  df-riota 6511  df-om 6958  df-wrecs 7294  df-recs 7355  df-rdg 7393  df-er 7629  df-en 7842  df-dom 7843  df-sdom 7844  df-oi 8298  df-har 8346  df-card 8648  df-aleph 8649

This theorem is referenced by: (None)