MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  hausnei Structured version   Visualization version   GIF version

Theorem hausnei 21334
Description: Neighborhood property of a Hausdorff space. (Contributed by NM, 8-Mar-2007.)
Hypothesis
Ref Expression
ist0.1 𝑋 = 𝐽
Assertion
Ref Expression
hausnei ((𝐽 ∈ Haus ∧ (𝑃𝑋𝑄𝑋𝑃𝑄)) → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅))
Distinct variable groups:   𝑚,𝑛,𝐽   𝑃,𝑚,𝑛   𝑄,𝑚,𝑛
Allowed substitution hints:   𝑋(𝑚,𝑛)

Proof of Theorem hausnei
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 ist0.1 . . . . . . 7 𝑋 = 𝐽
21ishaus 21328 . . . . . 6 (𝐽 ∈ Haus ↔ (𝐽 ∈ Top ∧ ∀𝑥𝑋𝑦𝑋 (𝑥𝑦 → ∃𝑛𝐽𝑚𝐽 (𝑥𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅))))
32simprbi 483 . . . . 5 (𝐽 ∈ Haus → ∀𝑥𝑋𝑦𝑋 (𝑥𝑦 → ∃𝑛𝐽𝑚𝐽 (𝑥𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅)))
4 neeq1 2994 . . . . . . 7 (𝑥 = 𝑃 → (𝑥𝑦𝑃𝑦))
5 eleq1 2827 . . . . . . . . 9 (𝑥 = 𝑃 → (𝑥𝑛𝑃𝑛))
653anbi1d 1552 . . . . . . . 8 (𝑥 = 𝑃 → ((𝑥𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅) ↔ (𝑃𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅)))
762rexbidv 3195 . . . . . . 7 (𝑥 = 𝑃 → (∃𝑛𝐽𝑚𝐽 (𝑥𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅) ↔ ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅)))
84, 7imbi12d 333 . . . . . 6 (𝑥 = 𝑃 → ((𝑥𝑦 → ∃𝑛𝐽𝑚𝐽 (𝑥𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅)) ↔ (𝑃𝑦 → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅))))
9 neeq2 2995 . . . . . . 7 (𝑦 = 𝑄 → (𝑃𝑦𝑃𝑄))
10 eleq1 2827 . . . . . . . . 9 (𝑦 = 𝑄 → (𝑦𝑚𝑄𝑚))
11103anbi2d 1553 . . . . . . . 8 (𝑦 = 𝑄 → ((𝑃𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅) ↔ (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅)))
12112rexbidv 3195 . . . . . . 7 (𝑦 = 𝑄 → (∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅) ↔ ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅)))
139, 12imbi12d 333 . . . . . 6 (𝑦 = 𝑄 → ((𝑃𝑦 → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅)) ↔ (𝑃𝑄 → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅))))
148, 13rspc2v 3461 . . . . 5 ((𝑃𝑋𝑄𝑋) → (∀𝑥𝑋𝑦𝑋 (𝑥𝑦 → ∃𝑛𝐽𝑚𝐽 (𝑥𝑛𝑦𝑚 ∧ (𝑛𝑚) = ∅)) → (𝑃𝑄 → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅))))
153, 14syl5 34 . . . 4 ((𝑃𝑋𝑄𝑋) → (𝐽 ∈ Haus → (𝑃𝑄 → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅))))
1615ex 449 . . 3 (𝑃𝑋 → (𝑄𝑋 → (𝐽 ∈ Haus → (𝑃𝑄 → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅)))))
1716com3r 87 . 2 (𝐽 ∈ Haus → (𝑃𝑋 → (𝑄𝑋 → (𝑃𝑄 → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅)))))
18173imp2 1443 1 ((𝐽 ∈ Haus ∧ (𝑃𝑋𝑄𝑋𝑃𝑄)) → ∃𝑛𝐽𝑚𝐽 (𝑃𝑛𝑄𝑚 ∧ (𝑛𝑚) = ∅))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 383  w3a 1072   = wceq 1632  wcel 2139  wne 2932  wral 3050  wrex 3051  cin 3714  c0 4058   cuni 4588  Topctop 20900  Hauscha 21314
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1871  ax-4 1886  ax-5 1988  ax-6 2054  ax-7 2090  ax-9 2148  ax-10 2168  ax-11 2183  ax-12 2196  ax-13 2391  ax-ext 2740
This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3an 1074  df-tru 1635  df-ex 1854  df-nf 1859  df-sb 2047  df-clab 2747  df-cleq 2753  df-clel 2756  df-nfc 2891  df-ne 2933  df-ral 3055  df-rex 3056  df-rab 3059  df-v 3342  df-uni 4589  df-haus 21321
This theorem is referenced by:  haust1  21358  cnhaus  21360  lmmo  21386  hauscmplem  21411  pthaus  21643  txhaus  21652  xkohaus  21658  hausflimi  21985  hauspwpwf1  21992
  Copyright terms: Public domain W3C validator