Metamath Proof Explorer


Theorem neipcfilu

Description: In an uniform space, a neighboring filter is a Cauchy filter base. (Contributed by Thierry Arnoux, 24-Jan-2018)

Ref Expression
Hypotheses neipcfilu.x 𝑋 = ( Base ‘ 𝑊 )
neipcfilu.j 𝐽 = ( TopOpen ‘ 𝑊 )
neipcfilu.u 𝑈 = ( UnifSt ‘ 𝑊 )
Assertion neipcfilu ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( CauFilu𝑈 ) )

Proof

Step Hyp Ref Expression
1 neipcfilu.x 𝑋 = ( Base ‘ 𝑊 )
2 neipcfilu.j 𝐽 = ( TopOpen ‘ 𝑊 )
3 neipcfilu.u 𝑈 = ( UnifSt ‘ 𝑊 )
4 simp2 ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → 𝑊 ∈ TopSp )
5 1 2 istps ( 𝑊 ∈ TopSp ↔ 𝐽 ∈ ( TopOn ‘ 𝑋 ) )
6 4 5 sylib ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → 𝐽 ∈ ( TopOn ‘ 𝑋 ) )
7 simp3 ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → 𝑃𝑋 )
8 7 snssd ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → { 𝑃 } ⊆ 𝑋 )
9 snnzg ( 𝑃𝑋 → { 𝑃 } ≠ ∅ )
10 7 9 syl ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → { 𝑃 } ≠ ∅ )
11 neifil ( ( 𝐽 ∈ ( TopOn ‘ 𝑋 ) ∧ { 𝑃 } ⊆ 𝑋 ∧ { 𝑃 } ≠ ∅ ) → ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( Fil ‘ 𝑋 ) )
12 6 8 10 11 syl3anc ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( Fil ‘ 𝑋 ) )
13 filfbas ( ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( Fil ‘ 𝑋 ) → ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( fBas ‘ 𝑋 ) )
14 12 13 syl ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( fBas ‘ 𝑋 ) )
15 eqid ( 𝑤 “ { 𝑃 } ) = ( 𝑤 “ { 𝑃 } )
16 imaeq1 ( 𝑣 = 𝑤 → ( 𝑣 “ { 𝑃 } ) = ( 𝑤 “ { 𝑃 } ) )
17 16 rspceeqv ( ( 𝑤𝑈 ∧ ( 𝑤 “ { 𝑃 } ) = ( 𝑤 “ { 𝑃 } ) ) → ∃ 𝑣𝑈 ( 𝑤 “ { 𝑃 } ) = ( 𝑣 “ { 𝑃 } ) )
18 15 17 mpan2 ( 𝑤𝑈 → ∃ 𝑣𝑈 ( 𝑤 “ { 𝑃 } ) = ( 𝑣 “ { 𝑃 } ) )
19 vex 𝑤 ∈ V
20 19 imaex ( 𝑤 “ { 𝑃 } ) ∈ V
21 eqid ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) = ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) )
22 21 elrnmpt ( ( 𝑤 “ { 𝑃 } ) ∈ V → ( ( 𝑤 “ { 𝑃 } ) ∈ ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) ↔ ∃ 𝑣𝑈 ( 𝑤 “ { 𝑃 } ) = ( 𝑣 “ { 𝑃 } ) ) )
23 20 22 ax-mp ( ( 𝑤 “ { 𝑃 } ) ∈ ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) ↔ ∃ 𝑣𝑈 ( 𝑤 “ { 𝑃 } ) = ( 𝑣 “ { 𝑃 } ) )
24 18 23 sylibr ( 𝑤𝑈 → ( 𝑤 “ { 𝑃 } ) ∈ ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) )
25 24 ad2antlr ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ( 𝑤 “ { 𝑃 } ) ∈ ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) )
26 1 3 2 isusp ( 𝑊 ∈ UnifSp ↔ ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝐽 = ( unifTop ‘ 𝑈 ) ) )
27 26 simplbi ( 𝑊 ∈ UnifSp → 𝑈 ∈ ( UnifOn ‘ 𝑋 ) )
28 27 3ad2ant1 ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → 𝑈 ∈ ( UnifOn ‘ 𝑋 ) )
29 eqid ( unifTop ‘ 𝑈 ) = ( unifTop ‘ 𝑈 )
30 29 utopsnneip ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋 ) → ( ( nei ‘ ( unifTop ‘ 𝑈 ) ) ‘ { 𝑃 } ) = ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) )
31 28 7 30 syl2anc ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ( ( nei ‘ ( unifTop ‘ 𝑈 ) ) ‘ { 𝑃 } ) = ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) )
32 31 eleq2d ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ( ( 𝑤 “ { 𝑃 } ) ∈ ( ( nei ‘ ( unifTop ‘ 𝑈 ) ) ‘ { 𝑃 } ) ↔ ( 𝑤 “ { 𝑃 } ) ∈ ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) ) )
33 32 ad3antrrr ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ( ( 𝑤 “ { 𝑃 } ) ∈ ( ( nei ‘ ( unifTop ‘ 𝑈 ) ) ‘ { 𝑃 } ) ↔ ( 𝑤 “ { 𝑃 } ) ∈ ran ( 𝑣𝑈 ↦ ( 𝑣 “ { 𝑃 } ) ) ) )
34 25 33 mpbird ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ( 𝑤 “ { 𝑃 } ) ∈ ( ( nei ‘ ( unifTop ‘ 𝑈 ) ) ‘ { 𝑃 } ) )
35 simpl1 ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ ( 𝑣𝑈𝑤𝑈 ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) ) → 𝑊 ∈ UnifSp )
36 35 3anassrs ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → 𝑊 ∈ UnifSp )
37 26 simprbi ( 𝑊 ∈ UnifSp → 𝐽 = ( unifTop ‘ 𝑈 ) )
38 36 37 syl ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → 𝐽 = ( unifTop ‘ 𝑈 ) )
39 38 fveq2d ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ( nei ‘ 𝐽 ) = ( nei ‘ ( unifTop ‘ 𝑈 ) ) )
40 39 fveq1d ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) = ( ( nei ‘ ( unifTop ‘ 𝑈 ) ) ‘ { 𝑃 } ) )
41 34 40 eleqtrrd ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ( 𝑤 “ { 𝑃 } ) ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) )
42 simpr ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 )
43 id ( 𝑎 = ( 𝑤 “ { 𝑃 } ) → 𝑎 = ( 𝑤 “ { 𝑃 } ) )
44 43 sqxpeqd ( 𝑎 = ( 𝑤 “ { 𝑃 } ) → ( 𝑎 × 𝑎 ) = ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) )
45 44 sseq1d ( 𝑎 = ( 𝑤 “ { 𝑃 } ) → ( ( 𝑎 × 𝑎 ) ⊆ 𝑣 ↔ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) )
46 45 rspcev ( ( ( 𝑤 “ { 𝑃 } ) ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ∃ 𝑎 ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ( 𝑎 × 𝑎 ) ⊆ 𝑣 )
47 41 42 46 syl2anc ( ( ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) ∧ 𝑤𝑈 ) ∧ ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) → ∃ 𝑎 ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ( 𝑎 × 𝑎 ) ⊆ 𝑣 )
48 28 adantr ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) → 𝑈 ∈ ( UnifOn ‘ 𝑋 ) )
49 7 adantr ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) → 𝑃𝑋 )
50 simpr ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) → 𝑣𝑈 )
51 simpll1 ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) → 𝑈 ∈ ( UnifOn ‘ 𝑋 ) )
52 simplr ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) → 𝑢𝑈 )
53 ustexsym ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑢𝑈 ) → ∃ 𝑤𝑈 ( 𝑤 = 𝑤𝑤𝑢 ) )
54 51 52 53 syl2anc ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) → ∃ 𝑤𝑈 ( 𝑤 = 𝑤𝑤𝑢 ) )
55 51 ad2antrr ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → 𝑈 ∈ ( UnifOn ‘ 𝑋 ) )
56 simplr ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → 𝑤𝑈 )
57 ustssxp ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑤𝑈 ) → 𝑤 ⊆ ( 𝑋 × 𝑋 ) )
58 55 56 57 syl2anc ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → 𝑤 ⊆ ( 𝑋 × 𝑋 ) )
59 simpll2 ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( ( 𝑢𝑢 ) ⊆ 𝑣𝑤𝑈 ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) ) → 𝑃𝑋 )
60 59 3anassrs ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → 𝑃𝑋 )
61 ustneism ( ( 𝑤 ⊆ ( 𝑋 × 𝑋 ) ∧ 𝑃𝑋 ) → ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ ( 𝑤 𝑤 ) )
62 58 60 61 syl2anc ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ ( 𝑤 𝑤 ) )
63 simprl ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → 𝑤 = 𝑤 )
64 63 coeq2d ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → ( 𝑤 𝑤 ) = ( 𝑤𝑤 ) )
65 coss1 ( 𝑤𝑢 → ( 𝑤𝑤 ) ⊆ ( 𝑢𝑤 ) )
66 coss2 ( 𝑤𝑢 → ( 𝑢𝑤 ) ⊆ ( 𝑢𝑢 ) )
67 65 66 sstrd ( 𝑤𝑢 → ( 𝑤𝑤 ) ⊆ ( 𝑢𝑢 ) )
68 67 ad2antll ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → ( 𝑤𝑤 ) ⊆ ( 𝑢𝑢 ) )
69 simpllr ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → ( 𝑢𝑢 ) ⊆ 𝑣 )
70 68 69 sstrd ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → ( 𝑤𝑤 ) ⊆ 𝑣 )
71 64 70 eqsstrd ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → ( 𝑤 𝑤 ) ⊆ 𝑣 )
72 62 71 sstrd ( ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) ∧ ( 𝑤 = 𝑤𝑤𝑢 ) ) → ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 )
73 72 ex ( ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) ∧ 𝑤𝑈 ) → ( ( 𝑤 = 𝑤𝑤𝑢 ) → ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) )
74 73 reximdva ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) → ( ∃ 𝑤𝑈 ( 𝑤 = 𝑤𝑤𝑢 ) → ∃ 𝑤𝑈 ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 ) )
75 54 74 mpd ( ( ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) ∧ 𝑢𝑈 ) ∧ ( 𝑢𝑢 ) ⊆ 𝑣 ) → ∃ 𝑤𝑈 ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 )
76 ustexhalf ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑣𝑈 ) → ∃ 𝑢𝑈 ( 𝑢𝑢 ) ⊆ 𝑣 )
77 76 3adant2 ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) → ∃ 𝑢𝑈 ( 𝑢𝑢 ) ⊆ 𝑣 )
78 75 77 r19.29a ( ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) ∧ 𝑃𝑋𝑣𝑈 ) → ∃ 𝑤𝑈 ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 )
79 48 49 50 78 syl3anc ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) → ∃ 𝑤𝑈 ( ( 𝑤 “ { 𝑃 } ) × ( 𝑤 “ { 𝑃 } ) ) ⊆ 𝑣 )
80 47 79 r19.29a ( ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) ∧ 𝑣𝑈 ) → ∃ 𝑎 ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ( 𝑎 × 𝑎 ) ⊆ 𝑣 )
81 80 ralrimiva ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ∀ 𝑣𝑈𝑎 ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ( 𝑎 × 𝑎 ) ⊆ 𝑣 )
82 iscfilu ( 𝑈 ∈ ( UnifOn ‘ 𝑋 ) → ( ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( CauFilu𝑈 ) ↔ ( ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( fBas ‘ 𝑋 ) ∧ ∀ 𝑣𝑈𝑎 ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ( 𝑎 × 𝑎 ) ⊆ 𝑣 ) ) )
83 28 82 syl ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ( ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( CauFilu𝑈 ) ↔ ( ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( fBas ‘ 𝑋 ) ∧ ∀ 𝑣𝑈𝑎 ∈ ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ( 𝑎 × 𝑎 ) ⊆ 𝑣 ) ) )
84 14 81 83 mpbir2and ( ( 𝑊 ∈ UnifSp ∧ 𝑊 ∈ TopSp ∧ 𝑃𝑋 ) → ( ( nei ‘ 𝐽 ) ‘ { 𝑃 } ) ∈ ( CauFilu𝑈 ) )