set US = ultraset BL;
set STP = { (union A) where A is Subset-Family of (ultraset BL) : A c= StoneR BL } ;
{ (union A) where A is Subset-Family of (ultraset BL) : A c= StoneR BL } is Subset-Family of (ultraset BL)
then reconsider STP = { (union A) where A is Subset-Family of (ultraset BL) : A c= StoneR BL } as Subset-Family of (ultraset BL) ;
TopStruct(# (ultraset BL),STP #) is strict TopSpace
proof
set TS =
TopStruct(#
(ultraset BL),
STP #);
A2:
the
carrier of
TopStruct(#
(ultraset BL),
STP #)
in the
topology of
TopStruct(#
(ultraset BL),
STP #)
A7:
for
a being
Subset-Family of
TopStruct(#
(ultraset BL),
STP #) st
a c= the
topology of
TopStruct(#
(ultraset BL),
STP #) holds
union a in the
topology of
TopStruct(#
(ultraset BL),
STP #)
for
p,
q being
Subset of
TopStruct(#
(ultraset BL),
STP #) st
p in the
topology of
TopStruct(#
(ultraset BL),
STP #) &
q in the
topology of
TopStruct(#
(ultraset BL),
STP #) holds
p /\ q in the
topology of
TopStruct(#
(ultraset BL),
STP #)
proof
let p,
q be
Subset of
TopStruct(#
(ultraset BL),
STP #);
:: thesis: ( p in the topology of TopStruct(# (ultraset BL),STP #) & q in the topology of TopStruct(# (ultraset BL),STP #) implies p /\ q in the topology of TopStruct(# (ultraset BL),STP #) )
assume A16:
(
p in the
topology of
TopStruct(#
(ultraset BL),
STP #) &
q in the
topology of
TopStruct(#
(ultraset BL),
STP #) )
;
:: thesis: p /\ q in the topology of TopStruct(# (ultraset BL),STP #)
then consider P being
Subset-Family of
(ultraset BL) such that A17:
(
union P = p &
P c= StoneR BL )
;
consider Q being
Subset-Family of
(ultraset BL) such that A18:
(
union Q = q &
Q c= StoneR BL )
by A16;
A19:
(union P) /\ (union Q) = union (INTERSECTION P,Q)
by SETFAM_1:39;
INTERSECTION P,
Q c= bool (ultraset BL)
then reconsider C =
INTERSECTION P,
Q as
Subset-Family of
(ultraset BL) ;
reconsider C =
C as
Subset-Family of
(ultraset BL) ;
C c= StoneR BL
proof
let x be
set ;
:: according to TARSKI:def 3 :: thesis: ( not x in C or x in StoneR BL )
assume
x in C
;
:: thesis: x in StoneR BL
then consider X,
Y being
set such that A22:
(
X in P &
Y in Q &
x = X /\ Y )
by SETFAM_1:def 5;
consider a being
Element of
BL such that A23:
X = (UFilter BL) . a
by A17, A22, Th26;
consider b being
Element of
BL such that A24:
Y = (UFilter BL) . b
by A18, A22, Th26;
A25:
X = { F where F is Filter of BL : ( F is being_ultrafilter & a in F ) }
by A23, Def6;
A26:
Y = { F where F is Filter of BL : ( F is being_ultrafilter & b in F ) }
by A24, Def6;
A27:
X /\ Y = { F where F is Filter of BL : ( F is being_ultrafilter & a "/\" b in F ) }
(UFilter BL) . (a "/\" b) = { F where F is Filter of BL : ( F is being_ultrafilter & a "/\" b in F ) }
by Def6;
then consider c being
Element of
BL such that A37:
(
c = a "/\" b &
(UFilter BL) . c = { F where F is Filter of BL : ( F is being_ultrafilter & c in F ) } )
;
thus
x in StoneR BL
by A22, A27, A37, Th26;
:: thesis: verum
end;
hence
p /\ q in the
topology of
TopStruct(#
(ultraset BL),
STP #)
by A17, A18, A19;
:: thesis: verum
end;
hence
TopStruct(#
(ultraset BL),
STP #) is
strict TopSpace
by A2, A7, PRE_TOPC:def 1;
:: thesis: verum
end;
then reconsider TS = TopStruct(# (ultraset BL),STP #) as strict TopSpace ;
take
TS
; :: thesis: ( the carrier of TS = ultraset BL & the topology of TS = { (union A) where A is Subset-Family of (ultraset BL) : A c= StoneR BL } )
thus
( the carrier of TS = ultraset BL & the topology of TS = { (union A) where A is Subset-Family of (ultraset BL) : A c= StoneR BL } )
; :: thesis: verum