Theorem hmphindis 23821

Description: Homeomorphisms preserve topological indiscreteness. (Contributed by FL, 18-Aug-2008.) (Revised by Mario Carneiro, 10-Sep-2015.)

Hypothesis

Ref	Expression
hmphdis.1	⊢ 𝑋 = ∪ 𝐽

Assertion

Ref	Expression
hmphindis	⊢ (𝐽 ≃ {∅, 𝐴} → 𝐽 = {∅, 𝑋})

Proof of Theorem hmphindis

Step	Hyp	Ref	Expression
1		dfsn2 4644	. . 3 ⊢ {∅} = {∅, ∅}
2		indislem 23023	. . . . . . 7 ⊢ {∅, ( I ‘𝐴)} = {∅, 𝐴}
3		preq2 4739	. . . . . . . 8 ⊢ (( I ‘𝐴) = ∅ → {∅, ( I ‘𝐴)} = {∅, ∅})
4	3, 1	eqtr4di 2793	. . . . . . 7 ⊢ (( I ‘𝐴) = ∅ → {∅, ( I ‘𝐴)} = {∅})
5	2, 4	eqtr3id 2789	. . . . . 6 ⊢ (( I ‘𝐴) = ∅ → {∅, 𝐴} = {∅})
6	5	breq2d 5160	. . . . 5 ⊢ (( I ‘𝐴) = ∅ → (𝐽 ≃ {∅, 𝐴} ↔ 𝐽 ≃ {∅}))
7	6	biimpac 478	. . . 4 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) = ∅) → 𝐽 ≃ {∅})
8		hmph0 23819	. . . 4 ⊢ (𝐽 ≃ {∅} ↔ 𝐽 = {∅})
9	7, 8	sylib 218	. . 3 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) = ∅) → 𝐽 = {∅})
10	9	unieqd 4925	. . . . 5 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) = ∅) → ∪ 𝐽 = ∪ {∅})
11		hmphdis.1	. . . . 5 ⊢ 𝑋 = ∪ 𝐽
12		0ex 5313	. . . . . . 7 ⊢ ∅ ∈ V
13	12	unisn 4931	. . . . . 6 ⊢ ∪ {∅} = ∅
14	13	eqcomi 2744	. . . . 5 ⊢ ∅ = ∪ {∅}
15	10, 11, 14	3eqtr4g 2800	. . . 4 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) = ∅) → 𝑋 = ∅)
16	15	preq2d 4745	. . 3 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) = ∅) → {∅, 𝑋} = {∅, ∅})
17	1, 9, 16	3eqtr4a 2801	. 2 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) = ∅) → 𝐽 = {∅, 𝑋})
18		hmphen 23809	. . . . 5 ⊢ (𝐽 ≃ {∅, 𝐴} → 𝐽 ≈ {∅, 𝐴})
19		necom 2992	. . . . . . . 8 ⊢ (( I ‘𝐴) ≠ ∅ ↔ ∅ ≠ ( I ‘𝐴))
20		fvex 6920	. . . . . . . . 9 ⊢ ( I ‘𝐴) ∈ V
21		enpr2 10040	. . . . . . . . 9 ⊢ ((∅ ∈ V ∧ ( I ‘𝐴) ∈ V ∧ ∅ ≠ ( I ‘𝐴)) → {∅, ( I ‘𝐴)} ≈ 2o)
22	12, 20, 21	mp3an12 1450	. . . . . . . 8 ⊢ (∅ ≠ ( I ‘𝐴) → {∅, ( I ‘𝐴)} ≈ 2o)
23	19, 22	sylbi 217	. . . . . . 7 ⊢ (( I ‘𝐴) ≠ ∅ → {∅, ( I ‘𝐴)} ≈ 2o)
24	23	adantl 481	. . . . . 6 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → {∅, ( I ‘𝐴)} ≈ 2o)
25	2, 24	eqbrtrrid 5184	. . . . 5 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → {∅, 𝐴} ≈ 2o)
26		entr 9045	. . . . 5 ⊢ ((𝐽 ≈ {∅, 𝐴} ∧ {∅, 𝐴} ≈ 2o) → 𝐽 ≈ 2o)
27	18, 25, 26	syl2an2r 685	. . . 4 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → 𝐽 ≈ 2o)
28		hmphtop1 23803	. . . . . . 7 ⊢ (𝐽 ≃ {∅, 𝐴} → 𝐽 ∈ Top)
29	28	adantr 480	. . . . . 6 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → 𝐽 ∈ Top)
30	11	toptopon 22939	. . . . . 6 ⊢ (𝐽 ∈ Top ↔ 𝐽 ∈ (TopOn‘𝑋))
31	29, 30	sylib 218	. . . . 5 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → 𝐽 ∈ (TopOn‘𝑋))
32		en2top 23008	. . . . 5 ⊢ (𝐽 ∈ (TopOn‘𝑋) → (𝐽 ≈ 2o ↔ (𝐽 = {∅, 𝑋} ∧ 𝑋 ≠ ∅)))
33	31, 32	syl 17	. . . 4 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → (𝐽 ≈ 2o ↔ (𝐽 = {∅, 𝑋} ∧ 𝑋 ≠ ∅)))
34	27, 33	mpbid 232	. . 3 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → (𝐽 = {∅, 𝑋} ∧ 𝑋 ≠ ∅))
35	34	simpld 494	. 2 ⊢ ((𝐽 ≃ {∅, 𝐴} ∧ ( I ‘𝐴) ≠ ∅) → 𝐽 = {∅, 𝑋})
36	17, 35	pm2.61dane 3027	1 ⊢ (𝐽 ≃ {∅, 𝐴} → 𝐽 = {∅, 𝑋})

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   = wceq 1537   ∈ wcel 2106   ≠ wne 2938  Vcvv 3478  ∅c0 4339  {csn 4631  {cpr 4633  ∪ cuni 4912   class class class wbr 5148   I cid 5582  ‘cfv 6563  2_oc2o 8499   ≈ cen 8981  Topctop 22915  TopOnctopon 22932   ≃ chmph 23778

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1792  ax-4 1806  ax-5 1908  ax-6 1965  ax-7 2005  ax-8 2108  ax-9 2116  ax-10 2139  ax-11 2155  ax-12 2175  ax-ext 2706  ax-sep 5302  ax-nul 5312  ax-pow 5371  ax-pr 5438  ax-un 7754

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3or 1087  df-3an 1088  df-tru 1540  df-fal 1550  df-ex 1777  df-nf 1781  df-sb 2063  df-mo 2538  df-eu 2567  df-clab 2713  df-cleq 2727  df-clel 2814  df-nfc 2890  df-ne 2939  df-ral 3060  df-rex 3069  df-reu 3379  df-rab 3434  df-v 3480  df-sbc 3792  df-csb 3909  df-dif 3966  df-un 3968  df-in 3970  df-ss 3980  df-pss 3983  df-nul 4340  df-if 4532  df-pw 4607  df-sn 4632  df-pr 4634  df-op 4638  df-uni 4913  df-int 4952  df-iun 4998  df-br 5149  df-opab 5211  df-mpt 5232  df-tr 5266  df-id 5583  df-eprel 5589  df-po 5597  df-so 5598  df-fr 5641  df-we 5643  df-xp 5695  df-rel 5696  df-cnv 5697  df-co 5698  df-dm 5699  df-rn 5700  df-res 5701  df-ima 5702  df-ord 6389  df-on 6390  df-lim 6391  df-suc 6392  df-iota 6516  df-fun 6565  df-fn 6566  df-f 6567  df-f1 6568  df-fo 6569  df-f1o 6570  df-fv 6571  df-ov 7434  df-oprab 7435  df-mpo 7436  df-om 7888  df-1st 8013  df-2nd 8014  df-1o 8505  df-2o 8506  df-er 8744  df-map 8867  df-en 8985  df-dom 8986  df-sdom 8987  df-fin 8988  df-card 9977  df-top 22916  df-topon 22933  df-cn 23251  df-hmeo 23779  df-hmph 23780

This theorem is referenced by: (None)