Theorem nosepon 27629

Description: Given two unequal surreals, the minimal ordinal at which they differ is an ordinal. (Contributed by Scott Fenton, 21-Sep-2020.)

Assertion

Ref	Expression
nosepon	⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ 𝐴 ≠ 𝐵) → ∩ {𝑥 ∈ On ∣ (𝐴‘𝑥) ≠ (𝐵‘𝑥)} ∈ On)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem nosepon

Step	Hyp	Ref	Expression
1		df-ne 2933	. . . . . . . 8 ⊢ ((𝐴‘𝑥) ≠ (𝐵‘𝑥) ↔ ¬ (𝐴‘𝑥) = (𝐵‘𝑥))
2	1	rexbii 3084	. . . . . . 7 ⊢ (∃𝑥 ∈ On (𝐴‘𝑥) ≠ (𝐵‘𝑥) ↔ ∃𝑥 ∈ On ¬ (𝐴‘𝑥) = (𝐵‘𝑥))
3	2	notbii 320	. . . . . 6 ⊢ (¬ ∃𝑥 ∈ On (𝐴‘𝑥) ≠ (𝐵‘𝑥) ↔ ¬ ∃𝑥 ∈ On ¬ (𝐴‘𝑥) = (𝐵‘𝑥))
4		dfral2 3088	. . . . . 6 ⊢ (∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥) ↔ ¬ ∃𝑥 ∈ On ¬ (𝐴‘𝑥) = (𝐵‘𝑥))
5	3, 4	bitr4i 278	. . . . 5 ⊢ (¬ ∃𝑥 ∈ On (𝐴‘𝑥) ≠ (𝐵‘𝑥) ↔ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥))
6		nodmord 27617	. . . . . . . . . . . . 13 ⊢ (𝐴 ∈ No → Ord dom 𝐴)
7		nodmord 27617	. . . . . . . . . . . . 13 ⊢ (𝐵 ∈ No → Ord dom 𝐵)
8		ordtri3or 6355	. . . . . . . . . . . . 13 ⊢ ((Ord dom 𝐴 ∧ Ord dom 𝐵) → (dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐴 = dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴))
9	6, 7, 8	syl2an 597	. . . . . . . . . . . 12 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐴 = dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴))
10		3orass 1090	. . . . . . . . . . . . 13 ⊢ ((dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐴 = dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴) ↔ (dom 𝐴 ∈ dom 𝐵 ∨ (dom 𝐴 = dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴)))
11		or12 921	. . . . . . . . . . . . 13 ⊢ ((dom 𝐴 ∈ dom 𝐵 ∨ (dom 𝐴 = dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴)) ↔ (dom 𝐴 = dom 𝐵 ∨ (dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴)))
12	10, 11	bitri 275	. . . . . . . . . . . 12 ⊢ ((dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐴 = dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴) ↔ (dom 𝐴 = dom 𝐵 ∨ (dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴)))
13	9, 12	sylib 218	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (dom 𝐴 = dom 𝐵 ∨ (dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴)))
14	13	ord 865	. . . . . . . . . 10 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (¬ dom 𝐴 = dom 𝐵 → (dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴)))
15		noseponlem 27628	. . . . . . . . . . . 12 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ dom 𝐴 ∈ dom 𝐵) → ¬ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥))
16	15	3expia 1122	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (dom 𝐴 ∈ dom 𝐵 → ¬ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)))
17		noseponlem 27628	. . . . . . . . . . . . . 14 ⊢ ((𝐵 ∈ No ∧ 𝐴 ∈ No ∧ dom 𝐵 ∈ dom 𝐴) → ¬ ∀𝑥 ∈ On (𝐵‘𝑥) = (𝐴‘𝑥))
18		eqcom 2743	. . . . . . . . . . . . . . 15 ⊢ ((𝐴‘𝑥) = (𝐵‘𝑥) ↔ (𝐵‘𝑥) = (𝐴‘𝑥))
19	18	ralbii 3083	. . . . . . . . . . . . . 14 ⊢ (∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥) ↔ ∀𝑥 ∈ On (𝐵‘𝑥) = (𝐴‘𝑥))
20	17, 19	sylnibr 329	. . . . . . . . . . . . 13 ⊢ ((𝐵 ∈ No ∧ 𝐴 ∈ No ∧ dom 𝐵 ∈ dom 𝐴) → ¬ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥))
21	20	3expia 1122	. . . . . . . . . . . 12 ⊢ ((𝐵 ∈ No ∧ 𝐴 ∈ No ) → (dom 𝐵 ∈ dom 𝐴 → ¬ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)))
22	21	ancoms 458	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (dom 𝐵 ∈ dom 𝐴 → ¬ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)))
23	16, 22	jaod 860	. . . . . . . . . 10 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → ((dom 𝐴 ∈ dom 𝐵 ∨ dom 𝐵 ∈ dom 𝐴) → ¬ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)))
24	14, 23	syld 47	. . . . . . . . 9 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (¬ dom 𝐴 = dom 𝐵 → ¬ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)))
25	24	con4d 115	. . . . . . . 8 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥) → dom 𝐴 = dom 𝐵))
26	25	3impia 1118	. . . . . . 7 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)) → dom 𝐴 = dom 𝐵)
27		ordsson 7737	. . . . . . . . . 10 ⊢ (Ord dom 𝐴 → dom 𝐴 ⊆ On)
28		ssralv 3990	. . . . . . . . . 10 ⊢ (dom 𝐴 ⊆ On → (∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥) → ∀𝑥 ∈ dom 𝐴(𝐴‘𝑥) = (𝐵‘𝑥)))
29	6, 27, 28	3syl 18	. . . . . . . . 9 ⊢ (𝐴 ∈ No → (∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥) → ∀𝑥 ∈ dom 𝐴(𝐴‘𝑥) = (𝐵‘𝑥)))
30	29	adantr 480	. . . . . . . 8 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥) → ∀𝑥 ∈ dom 𝐴(𝐴‘𝑥) = (𝐵‘𝑥)))
31	30	3impia 1118	. . . . . . 7 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)) → ∀𝑥 ∈ dom 𝐴(𝐴‘𝑥) = (𝐵‘𝑥))
32		nofun 27613	. . . . . . . . 9 ⊢ (𝐴 ∈ No → Fun 𝐴)
33	32	3ad2ant1 1134	. . . . . . . 8 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)) → Fun 𝐴)
34		nofun 27613	. . . . . . . . 9 ⊢ (𝐵 ∈ No → Fun 𝐵)
35	34	3ad2ant2 1135	. . . . . . . 8 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)) → Fun 𝐵)
36		eqfunfv 6988	. . . . . . . 8 ⊢ ((Fun 𝐴 ∧ Fun 𝐵) → (𝐴 = 𝐵 ↔ (dom 𝐴 = dom 𝐵 ∧ ∀𝑥 ∈ dom 𝐴(𝐴‘𝑥) = (𝐵‘𝑥))))
37	33, 35, 36	syl2anc 585	. . . . . . 7 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)) → (𝐴 = 𝐵 ↔ (dom 𝐴 = dom 𝐵 ∧ ∀𝑥 ∈ dom 𝐴(𝐴‘𝑥) = (𝐵‘𝑥))))
38	26, 31, 37	mpbir2and 714	. . . . . 6 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ ∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥)) → 𝐴 = 𝐵)
39	38	3expia 1122	. . . . 5 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (∀𝑥 ∈ On (𝐴‘𝑥) = (𝐵‘𝑥) → 𝐴 = 𝐵))
40	5, 39	biimtrid 242	. . . 4 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (¬ ∃𝑥 ∈ On (𝐴‘𝑥) ≠ (𝐵‘𝑥) → 𝐴 = 𝐵))
41	40	necon1ad 2949	. . 3 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ) → (𝐴 ≠ 𝐵 → ∃𝑥 ∈ On (𝐴‘𝑥) ≠ (𝐵‘𝑥)))
42	41	3impia 1118	. 2 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ 𝐴 ≠ 𝐵) → ∃𝑥 ∈ On (𝐴‘𝑥) ≠ (𝐵‘𝑥))
43		onintrab2 7751	. 2 ⊢ (∃𝑥 ∈ On (𝐴‘𝑥) ≠ (𝐵‘𝑥) ↔ ∩ {𝑥 ∈ On ∣ (𝐴‘𝑥) ≠ (𝐵‘𝑥)} ∈ On)
44	42, 43	sylib 218	1 ⊢ ((𝐴 ∈ No ∧ 𝐵 ∈ No ∧ 𝐴 ≠ 𝐵) → ∩ {𝑥 ∈ On ∣ (𝐴‘𝑥) ≠ (𝐵‘𝑥)} ∈ On)

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 206   ∧ wa 395   ∨ wo 848   ∨ w3o 1086   ∧ w3a 1087   = wceq 1542   ∈ wcel 2114   ≠ wne 2932  ∀wral 3051  ∃wrex 3061  {crab 3389   ⊆ wss 3889  ∩ cint 4889  dom cdm 5631  Ord word 6322  Oncon0 6323  Fun wfun 6492  ‘cfv 6498   No csur 27603

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2708  ax-sep 5231  ax-nul 5241  ax-pow 5307  ax-pr 5375  ax-un 7689

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ne 2933  df-ral 3052  df-rex 3062  df-rab 3390  df-v 3431  df-sbc 3729  df-csb 3838  df-dif 3892  df-un 3894  df-in 3896  df-ss 3906  df-pss 3909  df-nul 4274  df-if 4467  df-pw 4543  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4851  df-int 4890  df-br 5086  df-opab 5148  df-mpt 5167  df-tr 5193  df-id 5526  df-eprel 5531  df-po 5539  df-so 5540  df-fr 5584  df-we 5586  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-rn 5642  df-res 5643  df-ima 5644  df-ord 6326  df-on 6327  df-suc 6329  df-iota 6454  df-fun 6500  df-fn 6501  df-f 6502  df-fv 6506  df-1o 8405  df-2o 8406  df-no 27606

This theorem is referenced by:  nosepeq  27649  nosepssdm  27650  nodenselem4  27651  noresle  27661  nosupbnd2lem1  27679  noinfbnd2lem1  27694  noetasuplem4  27700  noetainflem4  27704