Metamath Proof Explorer


Theorem ustn0

Description: The empty set is not an uniform structure. (Contributed by Thierry Arnoux, 3-Dec-2017)

Ref Expression
Assertion ustn0 ¬ ran UnifOn

Proof

Step Hyp Ref Expression
1 noel ¬ x × x
2 0ex V
3 eleq2 u = x × x u x × x
4 2 3 elab u | x × x u x × x
5 1 4 mtbir ¬ u | x × x u
6 vex x V
7 velpw u 𝒫 𝒫 x × x u 𝒫 x × x
8 7 abbii u | u 𝒫 𝒫 x × x = u | u 𝒫 x × x
9 abid2 u | u 𝒫 𝒫 x × x = 𝒫 𝒫 x × x
10 6 6 xpex x × x V
11 10 pwex 𝒫 x × x V
12 11 pwex 𝒫 𝒫 x × x V
13 9 12 eqeltri u | u 𝒫 𝒫 x × x V
14 8 13 eqeltrri u | u 𝒫 x × x V
15 simp1 u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v u 𝒫 x × x
16 15 ss2abi u | u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v u | u 𝒫 x × x
17 14 16 ssexi u | u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v V
18 df-ust UnifOn = x V u | u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v
19 18 fvmpt2 x V u | u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v V UnifOn x = u | u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v
20 6 17 19 mp2an UnifOn x = u | u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v
21 simp2 u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v x × x u
22 21 ss2abi u | u 𝒫 x × x x × x u v u w 𝒫 x × x v w w u w u v w u I x v v -1 u w u w w v u | x × x u
23 20 22 eqsstri UnifOn x u | x × x u
24 23 sseli UnifOn x u | x × x u
25 5 24 mto ¬ UnifOn x
26 25 nex ¬ x UnifOn x
27 18 funmpt2 Fun UnifOn
28 elunirn Fun UnifOn ran UnifOn x dom UnifOn UnifOn x
29 27 28 ax-mp ran UnifOn x dom UnifOn UnifOn x
30 ustfn UnifOn Fn V
31 fndm UnifOn Fn V dom UnifOn = V
32 30 31 ax-mp dom UnifOn = V
33 32 rexeqi x dom UnifOn UnifOn x x V UnifOn x
34 rexv x V UnifOn x x UnifOn x
35 29 33 34 3bitri ran UnifOn x UnifOn x
36 26 35 mtbir ¬ ran UnifOn