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Theorem iscnrm4 49575
Description: A completely normal topology is a topology in which two separated sets can be separated by neighborhoods. (Contributed by Zhi Wang, 5-Sep-2024.)
Assertion
Ref Expression
iscnrm4 (𝐽 ∈ CNrm ↔ (𝐽 ∈ Top ∧ ∀𝑠 ∈ 𝒫 𝐽𝑡 ∈ 𝒫 𝐽(((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛 ∈ ((nei‘𝐽)‘𝑠)∃𝑚 ∈ ((nei‘𝐽)‘𝑡)(𝑛𝑚) = ∅)))
Distinct variable group:   𝑚,𝐽,𝑛,𝑠,𝑡

Proof of Theorem iscnrm4
StepHypRef Expression
1 iscnrm3 49573 . 2 (𝐽 ∈ CNrm ↔ (𝐽 ∈ Top ∧ ∀𝑠 ∈ 𝒫 𝐽𝑡 ∈ 𝒫 𝐽(((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛𝐽𝑚𝐽 (𝑠𝑛𝑡𝑚 ∧ (𝑛𝑚) = ∅))))
2 id 22 . . . . . 6 (𝐽 ∈ Top → 𝐽 ∈ Top)
32sepnsepo 49545 . . . . 5 (𝐽 ∈ Top → (∃𝑛 ∈ ((nei‘𝐽)‘𝑠)∃𝑚 ∈ ((nei‘𝐽)‘𝑡)(𝑛𝑚) = ∅ ↔ ∃𝑛𝐽𝑚𝐽 (𝑠𝑛𝑡𝑚 ∧ (𝑛𝑚) = ∅)))
43imbi2d 342 . . . 4 (𝐽 ∈ Top → ((((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛 ∈ ((nei‘𝐽)‘𝑠)∃𝑚 ∈ ((nei‘𝐽)‘𝑡)(𝑛𝑚) = ∅) ↔ (((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛𝐽𝑚𝐽 (𝑠𝑛𝑡𝑚 ∧ (𝑛𝑚) = ∅))))
542ralbidv 3226 . . 3 (𝐽 ∈ Top → (∀𝑠 ∈ 𝒫 𝐽𝑡 ∈ 𝒫 𝐽(((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛 ∈ ((nei‘𝐽)‘𝑠)∃𝑚 ∈ ((nei‘𝐽)‘𝑡)(𝑛𝑚) = ∅) ↔ ∀𝑠 ∈ 𝒫 𝐽𝑡 ∈ 𝒫 𝐽(((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛𝐽𝑚𝐽 (𝑠𝑛𝑡𝑚 ∧ (𝑛𝑚) = ∅))))
65pm5.32i 582 . 2 ((𝐽 ∈ Top ∧ ∀𝑠 ∈ 𝒫 𝐽𝑡 ∈ 𝒫 𝐽(((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛 ∈ ((nei‘𝐽)‘𝑠)∃𝑚 ∈ ((nei‘𝐽)‘𝑡)(𝑛𝑚) = ∅)) ↔ (𝐽 ∈ Top ∧ ∀𝑠 ∈ 𝒫 𝐽𝑡 ∈ 𝒫 𝐽(((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛𝐽𝑚𝐽 (𝑠𝑛𝑡𝑚 ∧ (𝑛𝑚) = ∅))))
71, 6bitr4i 280 1 (𝐽 ∈ CNrm ↔ (𝐽 ∈ Top ∧ ∀𝑠 ∈ 𝒫 𝐽𝑡 ∈ 𝒫 𝐽(((𝑠 ∩ ((cls‘𝐽)‘𝑡)) = ∅ ∧ (((cls‘𝐽)‘𝑠) ∩ 𝑡) = ∅) → ∃𝑛 ∈ ((nei‘𝐽)‘𝑠)∃𝑚 ∈ ((nei‘𝐽)‘𝑡)(𝑛𝑚) = ∅)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 208  wa 399  w3a 1098   = wceq 1560  wcel 2142  wral 3076  wrex 3086  cin 3903  wss 3904  c0 4285  𝒫 cpw 4555   cuni 4865  cfv 6521  Topctop 22953  clsccl 23078  neicnei 23157  CNrmccnrm 23371
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1815  ax-4 1829  ax-5 1930  ax-6 1987  ax-7 2028  ax-8 2144  ax-9 2152  ax-10 2175  ax-11 2191  ax-12 2212  ax-ext 2734  ax-rep 5227  ax-sep 5246  ax-nul 5256  ax-pow 5322  ax-pr 5390  ax-un 7718
This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3or 1099  df-3an 1100  df-tru 1563  df-fal 1573  df-ex 1800  df-nf 1804  df-sb 2091  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3077  df-rex 3087  df-reu 3368  df-rab 3415  df-v 3456  df-sbc 3745  df-csb 3853  df-dif 3907  df-un 3909  df-in 3911  df-ss 3921  df-pss 3924  df-nul 4286  df-if 4481  df-pw 4557  df-sn 4583  df-pr 4585  df-op 4589  df-uni 4866  df-int 4906  df-iun 4951  df-iin 4952  df-br 5101  df-opab 5163  df-mpt 5182  df-tr 5208  df-id 5542  df-eprel 5547  df-po 5555  df-so 5556  df-fr 5600  df-we 5602  df-xp 5653  df-rel 5654  df-cnv 5655  df-co 5656  df-dm 5657  df-rn 5658  df-res 5659  df-ima 5660  df-ord 6349  df-on 6350  df-lim 6351  df-suc 6352  df-iota 6477  df-fun 6523  df-fn 6524  df-f 6525  df-f1 6526  df-fo 6527  df-f1o 6528  df-fv 6529  df-ov 7399  df-oprab 7400  df-mpo 7401  df-om 7847  df-1st 7970  df-2nd 7971  df-en 8928  df-fin 8931  df-fi 9357  df-rest 17451  df-topgen 17472  df-top 22954  df-topon 22971  df-bases 23006  df-cld 23079  df-cls 23081  df-nei 23158  df-nrm 23377  df-cnrm 23378
This theorem is referenced by: (None)
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