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Theorem hauspwpwdom 21602
 Description: If 𝑋 is a Hausdorff space, then the cardinality of the closure of a set 𝐴 is bounded by the double powerset of 𝐴. In particular, a Hausdorff space with a dense subset 𝐴 has cardinality at most 𝒫 𝒫 𝐴, and a separable Hausdorff space has cardinality at most 𝒫 𝒫 ℕ. (Contributed by Mario Carneiro, 9-Apr-2015.) (Revised by Mario Carneiro, 28-Jul-2015.)
Hypothesis
Ref Expression
hauspwpwf1.x 𝑋 = 𝐽
Assertion
Ref Expression
hauspwpwdom ((𝐽 ∈ Haus ∧ 𝐴𝑋) → ((cls‘𝐽)‘𝐴) ≼ 𝒫 𝒫 𝐴)

Proof of Theorem hauspwpwdom
Dummy variables 𝑥 𝑦 𝑧 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 fvex 6113 . . 3 ((cls‘𝐽)‘𝐴) ∈ V
21a1i 11 . 2 ((𝐽 ∈ Haus ∧ 𝐴𝑋) → ((cls‘𝐽)‘𝐴) ∈ V)
3 haustop 20945 . . . . . 6 (𝐽 ∈ Haus → 𝐽 ∈ Top)
4 hauspwpwf1.x . . . . . . 7 𝑋 = 𝐽
54topopn 20536 . . . . . 6 (𝐽 ∈ Top → 𝑋𝐽)
63, 5syl 17 . . . . 5 (𝐽 ∈ Haus → 𝑋𝐽)
76adantr 480 . . . 4 ((𝐽 ∈ Haus ∧ 𝐴𝑋) → 𝑋𝐽)
8 simpr 476 . . . 4 ((𝐽 ∈ Haus ∧ 𝐴𝑋) → 𝐴𝑋)
97, 8ssexd 4733 . . 3 ((𝐽 ∈ Haus ∧ 𝐴𝑋) → 𝐴 ∈ V)
10 pwexg 4776 . . 3 (𝐴 ∈ V → 𝒫 𝐴 ∈ V)
11 pwexg 4776 . . 3 (𝒫 𝐴 ∈ V → 𝒫 𝒫 𝐴 ∈ V)
129, 10, 113syl 18 . 2 ((𝐽 ∈ Haus ∧ 𝐴𝑋) → 𝒫 𝒫 𝐴 ∈ V)
13 eqid 2610 . . 3 (𝑥 ∈ ((cls‘𝐽)‘𝐴) ↦ {𝑧 ∣ ∃𝑦𝐽 (𝑥𝑦𝑧 = (𝑦𝐴))}) = (𝑥 ∈ ((cls‘𝐽)‘𝐴) ↦ {𝑧 ∣ ∃𝑦𝐽 (𝑥𝑦𝑧 = (𝑦𝐴))})
144, 13hauspwpwf1 21601 . 2 ((𝐽 ∈ Haus ∧ 𝐴𝑋) → (𝑥 ∈ ((cls‘𝐽)‘𝐴) ↦ {𝑧 ∣ ∃𝑦𝐽 (𝑥𝑦𝑧 = (𝑦𝐴))}):((cls‘𝐽)‘𝐴)–1-1→𝒫 𝒫 𝐴)
15 f1dom2g 7859 . 2 ((((cls‘𝐽)‘𝐴) ∈ V ∧ 𝒫 𝒫 𝐴 ∈ V ∧ (𝑥 ∈ ((cls‘𝐽)‘𝐴) ↦ {𝑧 ∣ ∃𝑦𝐽 (𝑥𝑦𝑧 = (𝑦𝐴))}):((cls‘𝐽)‘𝐴)–1-1→𝒫 𝒫 𝐴) → ((cls‘𝐽)‘𝐴) ≼ 𝒫 𝒫 𝐴)
162, 12, 14, 15syl3anc 1318 1 ((𝐽 ∈ Haus ∧ 𝐴𝑋) → ((cls‘𝐽)‘𝐴) ≼ 𝒫 𝒫 𝐴)
 Colors of variables: wff setvar class Syntax hints:   → wi 4   ∧ wa 383   = wceq 1475   ∈ wcel 1977  {cab 2596  ∃wrex 2897  Vcvv 3173   ∩ cin 3539   ⊆ wss 3540  𝒫 cpw 4108  ∪ cuni 4372   class class class wbr 4583   ↦ cmpt 4643  –1-1→wf1 5801  ‘cfv 5804   ≼ cdom 7839  Topctop 20517  clsccl 20632  Hauscha 20922 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 This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  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-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-op 4132  df-uni 4373  df-int 4411  df-iun 4457  df-iin 4458  df-br 4584  df-opab 4644  df-mpt 4645  df-id 4953  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-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-dom 7843  df-top 20521  df-cld 20633  df-ntr 20634  df-cls 20635  df-haus 20929 This theorem is referenced by: (None)
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