Metamath Proof Explorer


Theorem toplatglb0

Description: The empty intersection in a topology is realized by the base set. (Contributed by Zhi Wang, 30-Sep-2024)

Ref Expression
Hypotheses topclat.i
|- I = ( toInc ` J )
toplatlub.j
|- ( ph -> J e. Top )
toplatglb0.g
|- G = ( glb ` I )
Assertion toplatglb0
|- ( ph -> ( G ` (/) ) = U. J )

Proof

Step Hyp Ref Expression
1 topclat.i
 |-  I = ( toInc ` J )
2 toplatlub.j
 |-  ( ph -> J e. Top )
3 toplatglb0.g
 |-  G = ( glb ` I )
4 3 a1i
 |-  ( ph -> G = ( glb ` I ) )
5 eqid
 |-  U. J = U. J
6 5 topopn
 |-  ( J e. Top -> U. J e. J )
7 2 6 syl
 |-  ( ph -> U. J e. J )
8 1 4 7 ipoglb0
 |-  ( ph -> ( G ` (/) ) = U. J )