let BL be non trivial B_Lattice; :: thesis: StoneR BL = OpenClosedSet (StoneSpace BL)
A1: StoneR BL c= OpenClosedSet (StoneSpace BL) by Lm2;
OpenClosedSet (StoneSpace BL) c= StoneR BL
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in OpenClosedSet (StoneSpace BL) or x in StoneR BL )
assume A2: x in OpenClosedSet (StoneSpace BL) ; :: thesis: x in StoneR BL
then reconsider X = x as Subset of (StoneSpace BL) ;
A3: the topology of (StoneSpace BL) = { (union A) where A is Subset-Family of (ultraset BL) : A c= StoneR BL } by Def8;
A4: ( X is open & X is closed ) by A2, Th2, Th3;
then A5: ( X ` is open & X ` is closed ) ;
X in the topology of (StoneSpace BL) by A4, PRE_TOPC:def 5;
then consider A1 being Subset-Family of (ultraset BL) such that
A6: X = union A1 and
A7: A1 c= StoneR BL by A3;
X ` in the topology of (StoneSpace BL) by A5, PRE_TOPC:def 5;
then consider A2 being Subset-Family of (ultraset BL) such that
A8: X ` = union A2 and
A9: A2 c= StoneR BL by A3;
A10: X is Subset of (ultraset BL) by Def8;
set AA = A1 \/ A2;
A11: ultraset BL = [#] (StoneSpace BL) by Def8
.= X \/ (X ` ) by PRE_TOPC:18
.= union (A1 \/ A2) by A6, A8, ZFMISC_1:96 ;
A12: A1 \/ A2 c= StoneR BL by A7, A9, XBOOLE_1:8;
then consider Y being Finite_Subset of (A1 \/ A2) such that
A13: ultraset BL = union Y by A11, Th38;
A14: Y c= A1 \/ A2 by FINSUB_1:def 5;
then A15: Y c= StoneR BL by A12, XBOOLE_1:1;
set D = A1 /\ Y;
A16: Y = (A1 \/ A2) /\ Y by A14, XBOOLE_1:28
.= (A1 /\ Y) \/ (A2 /\ Y) by XBOOLE_1:23 ;
now end;
then A18: X c= union (A1 /\ Y) by A10, A13, A16, SETFAM_1:57;
per cases ( A1 /\ Y = {} or A1 /\ Y <> {} ) ;
suppose A20: A1 /\ Y <> {} ; :: thesis: x in StoneR BL
A21: A1 /\ Y c= Y by XBOOLE_1:17;
reconsider D = A1 /\ Y as non empty Subset-Family of (ultraset BL) by A20;
reconsider D = D as non empty Subset-Family of (ultraset BL) ;
A22: union D c= (union A1) /\ (union Y) by ZFMISC_1:97;
(union A1) /\ (union Y) c= union A1 by XBOOLE_1:17;
then union D c= X by A6, A22, XBOOLE_1:1;
then A23: X = union D by A18, XBOOLE_0:def 10;
A24: D c= rng (UFilter BL) by A15, A21, XBOOLE_1:1;
A25: rng (UFilter BL) = dom (id (StoneR BL)) by FUNCT_2:def 1;
A26: dom (UFilter BL) = dom (UFilter BL) ;
UFilter BL = (id (StoneR BL)) * (UFilter BL) by RELAT_1:80;
then UFilter BL, id (StoneR BL) are_fiberwise_equipotent by A25, A26, CLASSES1:85;
then card ((UFilter BL) " D) = card ((id (StoneR BL)) " D) by CLASSES1:86
.= card D by A24, FUNCT_2:171 ;
then (UFilter BL) " D is finite ;
then reconsider B = (UFilter BL) " D as Finite_Subset of the carrier of BL by FINSUB_1:def 5;
A28: D = (UFilter BL) .: B by A15, A21, FUNCT_1:147, XBOOLE_1:1;
then A29: not B is empty by RELAT_1:149;
deffunc H1( Subset of (ultraset BL), Subset of (ultraset BL)) -> Element of bool (ultraset BL) = $1 \/ $2;
consider G being BinOp of (bool (ultraset BL)) such that
A33: for x, y being Subset of (ultraset BL) holds G . x,y = H1(x,y) from BINOP_1:sch 4();
A34: G is commutative
proof
let x, y be Subset of (ultraset BL); :: according to BINOP_1:def 13 :: thesis: G . x,y = G . y,x
G . x,y = y \/ x by A33
.= G . y,x by A33 ;
hence G . x,y = G . y,x ; :: thesis: verum
end;
A35: G is associative
proof
let x, y, z be Subset of (ultraset BL); :: according to BINOP_1:def 14 :: thesis: G . x,(G . y,z) = G . (G . x,y),z
G . x,(G . y,z) = G . x,(y \/ z) by A33
.= x \/ (y \/ z) by A33
.= (x \/ y) \/ z by XBOOLE_1:4
.= G . (x \/ y),z by A33
.= G . (G . x,y),z by A33 ;
hence G . x,(G . y,z) = G . (G . x,y),z ; :: thesis: verum
end;
A36: G is idempotent
proof
let x be Subset of (ultraset BL); :: according to BINOP_1:def 15 :: thesis: G . x,x = x
G . x,x = x \/ x by A33
.= x ;
hence G . x,x = x ; :: thesis: verum
end;
A37: for x, y being Element of BL holds (UFilter BL) . (the L_join of BL . x,y) = G . ((UFilter BL) . x),((UFilter BL) . y)
proof
let x, y be Element of BL; :: thesis: (UFilter BL) . (the L_join of BL . x,y) = G . ((UFilter BL) . x),((UFilter BL) . y)
thus (UFilter BL) . (the L_join of BL . x,y) = (UFilter BL) . (x "\/" y)
.= ((UFilter BL) . x) \/ ((UFilter BL) . y) by Th24
.= G . ((UFilter BL) . x),((UFilter BL) . y) by A33 ; :: thesis: verum
end;
reconsider DD = D as Element of Fin (bool (ultraset BL)) by FINSUB_1:def 5;
id BL = id the carrier of BL ;
then A38: (UFilter BL) . (FinJoin B) = (UFilter BL) . (FinJoin B,(id the carrier of BL)) by LATTICE4:def 12
.= (UFilter BL) . (the L_join of BL $$ B,(id the carrier of BL)) by LATTICE2:def 3
.= G $$ B,((UFilter BL) * (id the carrier of BL)) by A29, A34, A35, A36, A37, SETWISEO:39
.= G $$ B,(UFilter BL) by FUNCT_2:23
.= G $$ B,((id (bool (ultraset BL))) * (UFilter BL)) by FUNCT_2:23
.= G $$ DD,(id (bool (ultraset BL))) by A28, A29, A34, A35, A36, SETWISEO:38 ;
defpred S1[ Element of Fin (bool (ultraset BL))] means for D being non empty Subset-Family of (ultraset BL) st D = $1 holds
G $$ $1,(id (bool (ultraset BL))) = union D;
A39: S1[ {}. (bool (ultraset BL))] ;
A40: for DD being Element of Fin (bool (ultraset BL))
for b being Subset of (ultraset BL) st S1[DD] holds
S1[DD \/ {.b.}]
proof
let DD be Element of Fin (bool (ultraset BL)); :: thesis: for b being Subset of (ultraset BL) st S1[DD] holds
S1[DD \/ {.b.}]

let b be Subset of (ultraset BL); :: thesis: ( S1[DD] implies S1[DD \/ {.b.}] )
assume A41: for D being non empty Subset-Family of (ultraset BL) st D = DD holds
G $$ DD,(id (bool (ultraset BL))) = union D ; :: thesis: S1[DD \/ {.b.}]
let D be non empty Subset-Family of (ultraset BL); :: thesis: ( D = DD \/ {.b.} implies G $$ (DD \/ {.b.}),(id (bool (ultraset BL))) = union D )
assume A42: D = DD \/ {b} ; :: thesis: G $$ (DD \/ {.b.}),(id (bool (ultraset BL))) = union D
now
per cases ( DD is empty or not DD is empty ) ;
suppose A43: DD is empty ; :: thesis: G $$ (DD \/ {.b.}),(id (bool (ultraset BL))) = union D
hence G $$ (DD \/ {.b.}),(id (bool (ultraset BL))) = (id (bool (ultraset BL))) . b by A34, A35, SETWISEO:26
.= b by FUNCT_1:35
.= union D by A42, A43, ZFMISC_1:31 ;
:: thesis: verum
end;
suppose A44: not DD is empty ; :: thesis: G $$ (DD \/ {.b.}),(id (bool (ultraset BL))) = union D
DD c= D by A42, XBOOLE_1:7;
then reconsider D1 = DD as non empty Subset-Family of (ultraset BL) by A44, XBOOLE_1:1;
reconsider D1 = D1 as non empty Subset-Family of (ultraset BL) ;
thus G $$ (DD \/ {.b.}),(id (bool (ultraset BL))) = G . (G $$ DD,(id (bool (ultraset BL)))),((id (bool (ultraset BL))) . b) by A34, A35, A36, A44, SETWISEO:29
.= G . (G $$ DD,(id (bool (ultraset BL)))),b by FUNCT_1:35
.= (G $$ DD,(id (bool (ultraset BL)))) \/ b by A33
.= (union D1) \/ b by A41
.= (union D1) \/ (union {b}) by ZFMISC_1:31
.= union D by A42, ZFMISC_1:96 ; :: thesis: verum
end;
end;
end;
hence G $$ (DD \/ {.b.}),(id (bool (ultraset BL))) = union D ; :: thesis: verum
end;
for DD being Element of Fin (bool (ultraset BL)) holds S1[DD] from SETWISEO:sch 4(A39, A40);
then (UFilter BL) . (FinJoin B) = x by A23, A38;
hence x in StoneR BL by FUNCT_2:6; :: thesis: verum
end;
end;
end;
hence StoneR BL = OpenClosedSet (StoneSpace BL) by A1, XBOOLE_0:def 10; :: thesis: verum