Copyright (c) 2000 Association of Mizar Users
environ vocabulary BOOLE, TARSKI, RELAT_2, ORDERS_1, QUANTAL1, YELLOW_1, WAYBEL_0, FILTER_2, LATTICE3, ORDINAL2, YELLOW_0, LATTICES, WAYBEL_2, REALSET1, YELLOW_9, WAYBEL11, BHSP_3, WAYBEL_9, PRE_TOPC, PROB_1, WAYBEL19, PRELAMB, CANTOR_1, SETFAM_1, DIRAF, SUBSET_1, FINSET_1, COMPTS_1, YELLOW_6, TOPS_1, WAYBEL29, YELLOW13, WAYBEL21, RELAT_1, PARTFUN1, FUNCT_3, FUNCT_1, TOPS_2, WAYBEL_3, RLVECT_3, TDLAT_3, CONNSP_2, FILTER_0, WAYBEL_8, WAYBEL_6, WAYBEL30; notation TARSKI, XBOOLE_0, ZFMISC_1, SUBSET_1, RELAT_1, RELSET_1, FUNCT_1, FUNCT_2, FUNCT_3, STRUCT_0, FINSET_1, REALSET1, ORDERS_1, PRE_TOPC, TOPS_1, TOPS_2, COMPTS_1, CONNSP_2, TDLAT_3, LATTICE3, BORSUK_1, CANTOR_1, YELLOW_0, WAYBEL_0, YELLOW_1, WAYBEL_1, YELLOW_3, YELLOW_4, WAYBEL_2, WAYBEL_3, YELLOW_6, YELLOW_8, WAYBEL_6, WAYBEL_8, WAYBEL_9, WAYBEL11, YELLOW_9, WAYBEL19, WAYBEL21, YELLOW13, WAYBEL29; constructors CANTOR_1, GROUP_1, TOPS_1, TOPS_2, TDLAT_3, YELLOW_4, YELLOW_8, WAYBEL_1, WAYBEL_6, WAYBEL_8, WAYBEL19, ORDERS_3, URYSOHN1, WAYBEL21, YELLOW13, WAYBEL29, MEMBERED; clusters STRUCT_0, FINSET_1, BORSUK_1, SUBSET_1, TEX_1, TOPS_1, CANTOR_1, LATTICE3, YELLOW_0, YELLOW_1, YELLOW_2, YELLOW_3, YELLOW_4, YELLOW_6, WAYBEL_0, WAYBEL_2, WAYBEL_3, WAYBEL_8, WAYBEL10, WAYBEL11, WAYBEL14, YELLOW_9, WAYBEL19, YELLOW12, WAYBEL_4, RELSET_1, YELLOW13, MEMBERED, ZFMISC_1; requirements BOOLE, SUBSET; definitions TARSKI, PRE_TOPC, LATTICE3, YELLOW_0, WAYBEL_0, WAYBEL_2, WAYBEL_3, YELLOW_8, YELLOW_9, WAYBEL19, WAYBEL11, YELLOW13, XBOOLE_0; theorems TARSKI, PRE_TOPC, ORDERS_1, TOPS_1, TOPS_2, BORSUK_1, CONNSP_2, TEX_2, TDLAT_3, COMPTS_1, CANTOR_1, LATTICE3, RELAT_1, ZFMISC_1, FUNCT_1, FUNCT_2, FUNCT_3, RELSET_1, YELLOW_0, YELLOW_1, YELLOW_2, YELLOW_3, YELLOW_4, YELLOW_6, YELLOW_8, WAYBEL_0, WAYBEL_2, WAYBEL_3, WAYBEL_8, YELLOW13, WAYBEL11, WAYBEL12, WAYBEL14, YELLOW_9, WAYBEL19, YELLOW12, WAYBEL21, WAYBEL29, SETFAM_1, XBOOLE_0, XBOOLE_1; schemes SETFAM_1, FINSET_1, YELLOW_2; begin theorem Th1: for x being set, D being non empty set holds x /\ union D = union {x /\ d where d is Element of D: not contradiction} proof let x be set, D be non empty set; hereby let a be set; assume a in x /\ union D; then A1: a in x & a in union D by XBOOLE_0:def 3; then consider Z being set such that A2: a in Z & Z in D by TARSKI:def 4; A3: a in x /\ Z by A1,A2,XBOOLE_0:def 3; x /\ Z in {x /\ d where d is Element of D: not contradiction} by A2; hence a in union {x /\ d where d is Element of D: not contradiction} by A3,TARSKI:def 4; end; let a be set; assume a in union {x /\ d where d is Element of D: not contradiction}; then consider Z being set such that A4: a in Z & Z in {x /\ d where d is Element of D: not contradiction} by TARSKI:def 4; consider d being Element of D such that A5: Z = x /\ d and not contradiction by A4; A6: a in x & a in d by A4,A5,XBOOLE_0:def 3; then a in union D by TARSKI:def 4; hence a in x /\ union D by A6,XBOOLE_0:def 3; end; theorem Th2: for R being non empty reflexive transitive RelStr, D being non empty directed Subset of InclPoset Ids R holds union D is Ideal of R proof let R be non empty reflexive transitive RelStr, D be non empty directed Subset of InclPoset Ids R; A1: Ids R = {X where X is Ideal of R: not contradiction} by WAYBEL_0:def 23; D c= the carrier of InclPoset Ids R; then A2: D c= Ids R by YELLOW_1:1; A3: D c= bool the carrier of R proof let d be set; assume d in D; then d in Ids R by A2; then ex I being Ideal of R st d = I & not contradiction by A1; hence thesis; end; consider d being Element of D; d in D; then d in Ids R by A2; then consider I being Ideal of R such that A4: d = I and not contradiction by A1; consider i being Element of I; A5: i in d by A4; A6: for X being Subset of R st X in D holds X is directed proof let X be Subset of R; assume X in D; then X in Ids R by A2; then ex I being Ideal of R st X = I & not contradiction by A1; hence thesis; end; A7: for X, Y being Subset of R st X in D & Y in D ex Z being Subset of R st Z in D & X \/ Y c= Z proof let X, Y be Subset of R; assume A8: X in D & Y in D; then reconsider X1 = X, Y1 = Y as Element of InclPoset Ids R ; consider Z1 being Element of InclPoset Ids R such that A9: Z1 in D & X1 <= Z1 & Y1 <= Z1 by A8,WAYBEL_0:def 1; Z1 in Ids R by A2,A9; then ex I being Ideal of R st Z1 = I & not contradiction by A1; then reconsider Z = Z1 as Subset of R; take Z; thus Z in D by A9; X1 c= Z1 & Y1 c= Z1 by A9,YELLOW_1:3; hence X \/ Y c= Z by XBOOLE_1:8; end; for X being Subset of R st X in D holds X is lower proof let X be Subset of R; assume X in D; then X in Ids R by A2; then ex I being Ideal of R st X = I & not contradiction by A1; hence thesis; end; hence thesis by A3,A5,A6,A7,TARSKI:def 4,WAYBEL_0:26,46; end; Lm1: now let R be non empty reflexive transitive RelStr, D be non empty directed Subset of InclPoset Ids R, UD be Element of InclPoset Ids R such that A1: UD = union D; thus D is_<=_than UD proof let d be Element of InclPoset Ids R; assume A2: d in D; d c= UD proof let a be set; assume a in d; hence a in UD by A1,A2,TARSKI:def 4; end; hence d <= UD by YELLOW_1:3; end; end; Lm2: now let R be non empty reflexive transitive RelStr, D be non empty directed Subset of InclPoset Ids R, UD be Element of InclPoset Ids R such that A1: UD = union D; thus for b being Element of InclPoset Ids R st b is_>=_than D holds UD <= b proof let b be Element of InclPoset Ids R such that A2: for a being Element of InclPoset Ids R st a in D holds b >= a; UD c= b proof let x be set; assume x in UD; then consider Z being set such that A3: x in Z & Z in D by A1,TARSKI:def 4; reconsider Z as Element of InclPoset Ids R by A3; b >= Z by A2,A3; then Z c= b by YELLOW_1:3; hence x in b by A3; end; hence UD <= b by YELLOW_1:3; end; end; :: Exercise 2.16 (i), p. 16 definition let R be non empty reflexive transitive RelStr; cluster InclPoset Ids R -> up-complete; coherence proof set I = InclPoset Ids R; let D be non empty directed Subset of I; reconsider UD = union D as Ideal of R by Th2; Ids R = {X where X is Ideal of R: not contradiction} by WAYBEL_0:def 23; then UD in Ids R; then UD in the carrier of InclPoset Ids R by YELLOW_1:1; then reconsider UD as Element of I; take UD; thus thesis by Lm1,Lm2; end; end; theorem Th3: for R being non empty reflexive transitive RelStr, D being non empty directed Subset of InclPoset Ids R holds sup D = union D proof let R be non empty reflexive transitive RelStr, D be non empty directed Subset of InclPoset Ids R; A1: ex_sup_of D,InclPoset Ids R by WAYBEL_0:75; A2: Ids R = {X where X is Ideal of R: not contradiction} by WAYBEL_0:def 23; reconsider UD = union D as Ideal of R by Th2; UD in Ids R by A2; then UD in the carrier of InclPoset Ids R by YELLOW_1:1; then reconsider UD as Element of InclPoset Ids R; D is_<=_than UD & for b being Element of InclPoset Ids R st b is_>=_than D holds UD <= b by Lm1,Lm2; hence sup D = union D by A1,YELLOW_0:def 9; end; theorem Th4: for R being Semilattice, D being non empty directed Subset of InclPoset Ids R, x being Element of InclPoset Ids R holds sup ({x} "/\" D) = union {x /\ d where d is Element of D: not contradiction} proof let R be Semilattice, D be non empty directed Subset of InclPoset Ids R, x be Element of InclPoset Ids R; set I = InclPoset Ids R, A = {x /\ d where d is Element of D: not contradiction}, xD = {x "/\" d where d is Element of I: d in D}; xD c= the carrier of I proof let a be set; assume a in xD; then ex d being Element of I st a = x "/\" d & d in D; hence thesis; end; then reconsider xD as Subset of I; A1: ex_sup_of {x} "/\" D,I by WAYBEL_2:1; then ex_sup_of xD,I by YELLOW_4:42; then A2: sup xD is_>=_than xD by YELLOW_0:def 9; hereby let a be set; assume A3: a in sup ({x} "/\" D); ex_sup_of D,I by WAYBEL_0:75; then sup ({x} "/\" D) <= x "/\" sup D by A1,YELLOW_4:53; then sup ({x} "/\" D) c= x "/\" sup D by YELLOW_1:3; then a in x "/\" sup D by A3; then a in x /\ sup D by YELLOW_2:45; then A4: a in x & a in sup D by XBOOLE_0:def 3; then a in union D by Th3; then consider d being set such that A5: a in d and A6: d in D by TARSKI:def 4; reconsider d as Element of I by A6; set A = {x /\ w where w is Element of D: not contradiction}; A7: x /\ d in A by A6; a in x /\ d by A4,A5,XBOOLE_0:def 3; hence a in union A by A7,TARSKI:def 4; end; let a be set; assume a in union A; then consider Z being set such that A8: a in Z and A9: Z in A by TARSKI:def 4; consider d being Element of D such that A10: Z = x /\ d and not contradiction by A9; reconsider d as Element of I; A11: x /\ d = x "/\" d by YELLOW_2:45; A12: xD = {x} "/\" D by YELLOW_4:42; then x "/\" d in {x} "/\" D; then sup xD >= x "/\" d by A2,A12,LATTICE3:def 9; then x "/\" d c= sup xD by YELLOW_1:3; then a in sup xD by A8,A10,A11; hence a in sup ({x} "/\" D) by YELLOW_4:42; end; :: Exercise 4.8 (i), p. 33 definition let R be Semilattice; cluster InclPoset Ids R -> satisfying_MC; coherence proof set I = InclPoset Ids R; let x be Element of I, D be non empty directed Subset of I; thus x "/\" sup D = x /\ sup D by YELLOW_2:45 .= x /\ union D by Th3 .= union {x /\ d where d is Element of D: not contradiction} by Th1 .= sup ({x} "/\" D) by Th4; end; end; definition let R be non empty trivial RelStr; cluster -> trivial TopAugmentation of R; coherence proof let T be TopAugmentation of R; the RelStr of T = the RelStr of R by YELLOW_9:def 4; hence thesis by TEX_2:4; end; end; theorem for S being Scott complete TopLattice, T being complete LATTICE, A being Scott TopAugmentation of T st the RelStr of S = the RelStr of T holds the TopRelStr of A = the TopRelStr of S proof let S be Scott complete TopLattice, T be complete LATTICE, A be Scott TopAugmentation of T such that A1: the RelStr of S = the RelStr of T; A2: the RelStr of A = the RelStr of S by A1,YELLOW_9:def 4; the topology of S = sigma S by WAYBEL14:23 .= sigma T by A1,YELLOW_9:52 .= the topology of A by YELLOW_9:51; hence the TopRelStr of A = the TopRelStr of S by A2; end; theorem for N being Lawson complete TopLattice, T being complete LATTICE, A being Lawson correct TopAugmentation of T st the RelStr of N = the RelStr of T holds the TopRelStr of A = the TopRelStr of N proof let N be Lawson complete TopLattice, T be complete LATTICE, A be Lawson correct TopAugmentation of T such that A1: the RelStr of N = the RelStr of T; A2: the RelStr of A = the RelStr of N by A1,YELLOW_9:def 4; consider l being lower correct TopAugmentation of T; consider S being Scott correct TopAugmentation of T; A3: the topology of l = omega T & the topology of S = sigma T by WAYBEL19:def 2,YELLOW_9:51; A4: the RelStr of S = the RelStr of T & the RelStr of l = the RelStr of T by YELLOW_9:def 4; A5: N is Refinement of S, l proof thus the carrier of N = (the carrier of S) \/ (the carrier of l) by A1,A4; (sigma N) \/ (omega N) is prebasis of N by WAYBEL19:def 3; then (sigma T) \/ (omega N) is prebasis of N by A1,YELLOW_9:52; hence (the topology of S) \/ (the topology of l) is prebasis of N by A1,A3,WAYBEL19:3; end; (the topology of S) \/ (the topology of l) c= bool the carrier of N proof let a be set; assume a in (the topology of S) \/ (the topology of l); then a in the topology of S or a in the topology of l by XBOOLE_0:def 2; hence a in bool the carrier of N by A1,A4; end; then reconsider X = (the topology of S) \/ (the topology of l) as Subset-Family of N by SETFAM_1:def 7; reconsider X as Subset-Family of N; the topology of N = UniCl FinMeetCl X by A5,YELLOW_9:56 .= lambda T by A1,A3,WAYBEL19:33 .= the topology of A by WAYBEL19:def 4; hence the TopRelStr of A = the TopRelStr of N by A2; end; theorem for N being Lawson complete TopLattice for S being Scott TopAugmentation of N for A being Subset of N, J being Subset of S st A = J & J is closed holds A is closed proof let N be Lawson complete TopLattice, S be Scott TopAugmentation of N, A be Subset of N, J be Subset of S such that A1: A = J; A2: the RelStr of N = the RelStr of S by YELLOW_9:def 4; assume J is closed; then A3: [#]S \ J is open by PRE_TOPC:def 6; A4: N is Lawson correct TopAugmentation of S by A2,YELLOW_9:def 4; [#]S = the carrier of S by PRE_TOPC:12 .= [#]N by A2,PRE_TOPC:12; hence [#]N \ A is open by A1,A3,A4,WAYBEL19:37; end; definition let A be complete LATTICE; cluster lambda A -> non empty; coherence proof consider S being Lawson correct TopAugmentation of A; InclPoset the topology of S is non trivial; hence thesis by WAYBEL19:def 4; end; end; definition let S be Scott complete TopLattice; cluster InclPoset sigma S -> complete non trivial; coherence proof InclPoset the topology of S is complete non trivial; hence thesis by WAYBEL14:23; end; end; definition let N be Lawson complete TopLattice; cluster InclPoset sigma N -> complete non trivial; coherence proof consider S being Scott TopAugmentation of N; A1: the RelStr of S = the RelStr of N by YELLOW_9:def 4; InclPoset sigma S is complete non trivial; hence thesis by A1,YELLOW_9:52; end; cluster InclPoset lambda N -> complete non trivial; coherence proof consider S being Lawson correct TopAugmentation of N; InclPoset the topology of S is complete non trivial; hence thesis by WAYBEL19:def 4; end; end; theorem Th8: for T being non empty reflexive RelStr holds sigma T c= {W\uparrow F where W, F is Subset of T: W in sigma T & F is finite} proof let T be non empty reflexive RelStr; let s be set; assume A1: s in sigma T; s\uparrow {}T = s; hence thesis by A1; end; theorem Th9: for N being Lawson complete TopLattice holds lambda N = the topology of N proof let N be Lawson complete TopLattice; N is Lawson correct TopAugmentation of N by YELLOW_9:44; hence thesis by WAYBEL19:def 4; end; theorem Th10: for N being Lawson complete TopLattice holds sigma N c= lambda N proof let N be Lawson complete TopLattice; set Z = {W\uparrow F where W, F is Subset of N: W in sigma N & F is finite}; Z is Basis of N by WAYBEL19:32; then Z c= the topology of N by CANTOR_1:def 2; then A1: Z c= lambda N by Th9; sigma N c= Z by Th8; hence sigma N c= lambda N by A1,XBOOLE_1:1; end; theorem for M, N being complete LATTICE st the RelStr of M = the RelStr of N holds lambda M = lambda N proof let M, N be complete LATTICE such that A1: the RelStr of M = the RelStr of N; A2: lambda M = UniCl FinMeetCl ((sigma M) \/ (omega M)) & lambda N = UniCl FinMeetCl ((sigma N) \/ (omega N)) by WAYBEL19:33; sigma M = sigma N & omega M = omega N by A1,WAYBEL19:3,YELLOW_9:52; hence lambda M = lambda N by A1,A2; end; theorem Th12: for N being Lawson complete TopLattice, X being Subset of N holds X in lambda N iff X is open proof let N be Lawson complete TopLattice, X be Subset of N; lambda N = the topology of N by Th9; hence X in lambda N iff X is open by PRE_TOPC:def 5; end; definition cluster trivial TopSpace-like -> Scott (reflexive non empty TopRelStr); coherence proof let T be reflexive non empty TopRelStr; assume T is trivial TopSpace-like; then reconsider W = T as trivial reflexive non empty TopSpace-like TopRelStr; W is Scott proof let S be Subset of W; thus S is open implies S is upper; thus thesis by TDLAT_3:17; end; hence thesis; end; end; definition cluster trivial -> Lawson (complete TopLattice); coherence proof let T be complete TopLattice; assume T is trivial; then reconsider W = T as trivial complete TopLattice; A1: the topology of W = {{}, the carrier of W} by TDLAT_3:def 2; consider N being Lawson correct TopAugmentation of W; the RelStr of T = the RelStr of N by YELLOW_9:def 4; then the topology of T = the topology of N by A1,TDLAT_3:def 2 .= lambda T by WAYBEL19:def 4 .= UniCl FinMeetCl ((sigma T) \/ (omega T)) by WAYBEL19:33; then FinMeetCl ((omega T) \/ (sigma T)) is Basis of T by YELLOW_9:22; hence (omega T) \/ (sigma T) is prebasis of T by YELLOW_9:23; end; end; definition cluster strict continuous lower-bounded meet-continuous Scott (complete TopLattice); existence proof consider A being strict trivial TopLattice; take A; thus thesis; end; end; definition cluster strict continuous compact Hausdorff Lawson (complete TopLattice); existence proof consider R being strict trivial complete TopLattice; take R; thus thesis; end; end; EmptySch { A() -> Scott TopLattice, X() -> set, F(set) -> set }: { F(w) where w is Element of A(): w in {} } = {} proof thus { F(w) where w is Element of A(): w in {} } c= {} proof let a be set such that A1: a in { F(w) where w is Element of A(): w in {} }; assume not a in {}; consider w being Element of A() such that A2: a = F(w) & w in {} by A1; thus thesis by A2; end; thus thesis by XBOOLE_1:2; end; theorem Th13: for N being meet-continuous LATTICE, A being Subset of N st A has_the_property_(S) holds uparrow A has_the_property_(S) proof let N be meet-continuous LATTICE, A be Subset of N such that A1: for D being non empty directed Subset of N st sup D in A ex y being Element of N st y in D & for x being Element of N st x in D & x >= y holds x in A; let D be non empty directed Subset of N; assume sup D in uparrow A; then consider a being Element of N such that A2: a <= sup D & a in A by WAYBEL_0:def 16; reconsider aa = {a} as non empty directed Subset of N by WAYBEL_0:5; a = sup ({a} "/\" D) by A2,WAYBEL_2:52; then consider y being Element of N such that A3: y in aa "/\" D & for x being Element of N st x in aa "/\" D & x >= y holds x in A by A1,A2; aa "/\" D = {a "/\" d where d is Element of N: d in D} by YELLOW_4:42; then consider d being Element of N such that A4: y = a "/\" d & d in D by A3; take d; thus d in D by A4; let x be Element of N such that A5: x in D & x >= d; y >= y by ORDERS_1:24; then A6: y in A by A3; d >= y by A4,YELLOW_0:23; then x >= y by A5,ORDERS_1:26; hence x in uparrow A by A6,WAYBEL_0:def 16; end; definition let N be meet-continuous LATTICE, A be property(S) Subset of N; cluster uparrow A -> property(S); coherence by Th13; end; :: Proposition 2.1 (i), p. 153 theorem Th14: for N being meet-continuous Lawson (complete TopLattice), S being Scott TopAugmentation of N, A being Subset of N st A in lambda N holds uparrow A in sigma S proof let N be meet-continuous Lawson (complete TopLattice), S be Scott TopAugmentation of N, A be Subset of N such that A1: A in lambda N; A2: the RelStr of N = the RelStr of S by YELLOW_9:def 4; then reconsider Y = A as Subset of S; reconsider UA = uparrow A as Subset of S by A2; A3: uparrow A = uparrow Y by A2,WAYBEL_0:13; A4: S is meet-continuous by A2,YELLOW12:14; A is open by A1,Th12; then A is property(S) by WAYBEL19:36; then Y is property(S) by A2,YELLOW12:19; then uparrow Y is property(S) by A4,Th13; then UA is open by A3,WAYBEL11:15; then uparrow A in the topology of S by PRE_TOPC:def 5; hence uparrow A in sigma S by WAYBEL14:23; end; theorem Th15: for N being meet-continuous Lawson (complete TopLattice) for S being Scott TopAugmentation of N for A being Subset of N, J being Subset of S st A = J holds A is open implies uparrow J is open proof let N be meet-continuous Lawson (complete TopLattice), S be Scott TopAugmentation of N, A be Subset of N, J be Subset of S such that A1: A = J; A2: the RelStr of N = the RelStr of S by YELLOW_9:def 4; assume A is open; then A in lambda N by Th12; then uparrow A in sigma S by Th14; then uparrow J in sigma S by A1,A2,WAYBEL_0:13; hence uparrow J is open by WAYBEL14:24; end; theorem Th16: for N being meet-continuous Lawson (complete TopLattice) for S being Scott TopAugmentation of N for x being Point of S, y being Point of N for J being Basis of y st x = y holds {uparrow A where A is Subset of N: A in J} is Basis of x proof let N be meet-continuous Lawson (complete TopLattice), S be Scott TopAugmentation of N, x be Point of S, y be Point of N, J be Basis of y such that A1: x = y; A2: the RelStr of N = the RelStr of S by YELLOW_9:def 4; set Z = {uparrow A where A is Subset of N: A in J}; set K = Z; K is Subset-Family of S proof K c= bool the carrier of S proof let k be set; assume k in K; then consider A being Subset of N such that A3: k = uparrow A and A in J; thus k in bool the carrier of S by A2,A3; end; hence thesis by SETFAM_1:def 7; end; then reconsider K as Subset-Family of S; K is Basis of x proof thus K c= the topology of S proof let k be set; assume k in K; then consider A being Subset of N such that A4: k = uparrow A and A5: A in J; reconsider A' = A as Subset of S by A2; A is open by A5,YELLOW_8:21; then uparrow A' is open by Th15; then uparrow A' in the topology of S by PRE_TOPC:def 5; hence k in the topology of S by A2,A4,WAYBEL_0:13; end; for k being set st k in K holds x in k proof let k be set; assume k in K; then consider A being Subset of N such that A6: k = uparrow A and A7: A in J; y in Intersect J by YELLOW_8:def 2; then A8: y in A by A7,CANTOR_1:10; A c= uparrow A by WAYBEL_0:16; hence x in k by A1,A6,A8; end; hence x in Intersect K by CANTOR_1:10; let sA be Subset of S such that A9: sA is open & x in sA; reconsider lA = sA as Subset of N by A2; sigma N c= lambda N by Th10; then A10: sigma S c= lambda N by A2,YELLOW_9:52; N is Lawson correct TopAugmentation of S by A2,YELLOW_9:def 4; then lA is open by A9,WAYBEL19:37; then lA in lambda N by Th12; then uparrow lA in sigma S by Th14; then A11: uparrow lA is open by A10,Th12; lA c= uparrow lA by WAYBEL_0:16; then consider lV1 being Subset of N such that A12: lV1 in J and A13: lV1 c= uparrow lA by A1,A9,A11,YELLOW_8:def 2; reconsider sUV = uparrow lV1 as Subset of S by A2; take sUV; thus sUV in K by A12; A14: sA = uparrow sA proof thus sA c= uparrow sA by WAYBEL_0:16; sA is upper by A9,WAYBEL11:def 4; hence thesis by WAYBEL_0:24; end; A15: uparrow sA = uparrow lA by A2,WAYBEL_0:13; lV1 is_coarser_than uparrow lA by A13,WAYBEL12:20; hence sUV c= sA by A14,A15,YELLOW12:28; end; hence Z is Basis of x; end; :: Proposition 2.1 (ii), p. 153 theorem Th17: for N being meet-continuous Lawson (complete TopLattice) for S being Scott TopAugmentation of N for X being upper Subset of N, Y being Subset of S st X = Y holds Int X = Int Y proof let N be meet-continuous Lawson (complete TopLattice), S be Scott TopAugmentation of N, X be upper Subset of N, Y be Subset of S such that A1: X = Y; A2: the RelStr of N = the RelStr of S by YELLOW_9:def 4; A3: Int X c= uparrow Int X by WAYBEL_0:16; reconsider sX = Int X as Subset of S by A2; reconsider K = uparrow Int X as Subset of S by A2; uparrow sX is open by Th15; then A4: K is open by A2,WAYBEL_0:13; K c= Y proof let a be set; assume A5: a in K; then reconsider x = a as Element of N; consider y being Element of N such that A6: y <= x & y in Int X by A5,WAYBEL_0:def 16; A7: Int X c= X by TOPS_1:44; uparrow X = X proof thus uparrow X c= X by WAYBEL_0:24; thus thesis by WAYBEL_0:16; end; hence a in Y by A1,A6,A7,WAYBEL_0:def 16; end; then uparrow Int X c= Int Y by A4,TOPS_1:56; hence Int X c= Int Y by A3,XBOOLE_1:1; reconsider A = Int Y as Subset of N by A2; N is Lawson correct TopAugmentation of S by A2,YELLOW_9:def 4; then A8: A is open by WAYBEL19:37; A c= X by A1,TOPS_1:44; hence Int Y c= Int X by A8,TOPS_1:56; end; :: Proposition 2.1 (iii), p. 153 theorem for N being meet-continuous Lawson (complete TopLattice) for S being Scott TopAugmentation of N for X being lower Subset of N, Y being Subset of S st X = Y holds Cl X = Cl Y proof let N be meet-continuous Lawson (complete TopLattice), S be Scott TopAugmentation of N, X be lower Subset of N, Y be Subset of S such that A1: X = Y; A2: the RelStr of N = the RelStr of S by YELLOW_9:def 4; A4: X` = Y` by A1,A2; reconsider A = Cl Y as Subset of N by A2; (Cl X)` = (Cl X``)` .= Int X` by TOPS_1:def 1 .= Int Y` by A4,Th17 .= (Cl Y``)` by TOPS_1:def 1 .= A` by A2; hence Cl X = Cl Y by TOPS_1:21; end; theorem Th19: for M, N being complete LATTICE, LM being Lawson correct TopAugmentation of M, LN being Lawson correct TopAugmentation of N st InclPoset sigma N is continuous holds the topology of [:LM,LN qua TopSpace:] = lambda [:M,N:] proof let M, N be complete LATTICE, LM be Lawson correct TopAugmentation of M, LN be Lawson correct TopAugmentation of N such that A1: InclPoset sigma N is continuous; consider LMN being non empty Lawson correct TopAugmentation of [:M,N:]; consider lMN being non empty lower correct TopAugmentation of [:M,N:]; consider SMN being non empty Scott correct TopAugmentation of [:M,N:]; A2: LMN is Refinement of SMN, lMN by WAYBEL19:29; [:LM,LN qua TopSpace:] = the TopStruct of LMN proof consider SM being non empty Scott correct TopAugmentation of M; consider SN being non empty Scott correct TopAugmentation of N; consider lM being non empty lower correct TopAugmentation of M; consider lN being non empty lower correct TopAugmentation of N; A3: LM is Refinement of SM, lM & LN is Refinement of SN, lN by WAYBEL19:29; A4: the RelStr of SM = the RelStr of M & the RelStr of SN = the RelStr of N & the RelStr of lM = the RelStr of M & the RelStr of lN = the RelStr of N by YELLOW_9:def 4; A5: the RelStr of LM = the RelStr of M & the RelStr of LN = the RelStr of N by YELLOW_9:def 4; A6: the RelStr of LMN = the RelStr of [:M,N:] by YELLOW_9:def 4; A7: the carrier of [:LM,LN qua TopSpace:] = [:the carrier of LM,the carrier of LN:] by BORSUK_1:def 5 .= the carrier of LMN by A5,A6,YELLOW_3:def 2; the TopStruct of LMN is Refinement of [:SM,SN qua TopSpace:], [:lM,lN qua TopSpace:] proof [:LM,LN qua TopSpace:] is Refinement of [:SM,SN qua TopSpace:], [:lM,lN qua TopSpace:] by A3,A4,YELLOW12:50; hence the carrier of the TopStruct of LMN = (the carrier of [:SM,SN qua TopSpace:]) \/ (the carrier of [:lM,lN qua TopSpace:]) by A7,YELLOW_9:def 6; A8: (omega LMN) \/ (sigma LMN) is prebasis of LMN by WAYBEL19:def 3; A9: the topology of [:lM,lN qua TopSpace:] = omega [:M,N:] by WAYBEL19:15 .= omega LMN by A6,WAYBEL19:3; A10: the RelStr of SN = the RelStr of N by YELLOW_9:def 4 .= the RelStr of Sigma N by YELLOW_9:def 4; the RelStr of SM = the RelStr of M by YELLOW_9:def 4 .= the RelStr of Sigma M by YELLOW_9:def 4; then the TopStruct of SN = the TopStruct of Sigma N & the TopStruct of SM = the TopStruct of Sigma M by A10,WAYBEL29:17; then the topology of [:SM,SN qua TopSpace:] = the topology of [:Sigma M,(Sigma N) qua TopSpace:] by WAYBEL29:10 .= sigma [:M,N:] by A1,WAYBEL29:34 .= sigma LMN by A6,YELLOW_9:52; hence (the topology of [:SM,SN qua TopSpace:]) \/ (the topology of [:lM,lN qua TopSpace:]) is prebasis of the TopStruct of LMN by A8,A9,YELLOW12:33; end; hence thesis by A3,A4,A7,YELLOW12:49; end; then reconsider R = [:LM,LN qua TopSpace:] as Refinement of SMN, lMN by A2,YELLOW12:47; the topology of [:LM,LN qua TopSpace:] = the topology of R; hence thesis by WAYBEL19:34; end; :: Proposition 2.2, p. 153 theorem Th20: for M, N being complete LATTICE, P being Lawson correct TopAugmentation of [:M,N:], Q being Lawson correct TopAugmentation of M, R being Lawson correct TopAugmentation of N st InclPoset sigma N is continuous holds the TopStruct of P = [:Q,R qua TopSpace:] proof let M, N be complete LATTICE, P be Lawson correct TopAugmentation of [:M,N:], Q be Lawson correct TopAugmentation of M, R be Lawson correct TopAugmentation of N such that A1: InclPoset sigma N is continuous; A2: the RelStr of P = the RelStr of [:M,N:] & the RelStr of Q = the RelStr of M & the RelStr of R = the RelStr of N by YELLOW_9:def 4; then A3: the carrier of P = [:the carrier of Q, the carrier of N:] by YELLOW_3: def 2 .= the carrier of [:Q,R qua TopSpace:] by A2,BORSUK_1:def 5; the topology of P = lambda [:M,N:] by WAYBEL19:def 4 .= the topology of [:Q,R qua TopSpace:] by A1,Th19; hence the TopStruct of P = [:Q,R qua TopSpace:] by A3; end; :: Theorem 2.3, p. 153, first conjunct theorem Th21: for N being meet-continuous Lawson (complete TopLattice), x being Element of N holds x"/\" is continuous proof let N be meet-continuous Lawson (complete TopLattice), x be Element of N; for X being non empty Subset of N holds x"/\" preserves_inf_of X by YELLOW13:11; hence x"/\" is continuous by WAYBEL21:45; end; definition let N be meet-continuous Lawson (complete TopLattice), x be Element of N; cluster x"/\" -> continuous; coherence by Th21; end; :: Theorem 2.3, p. 153, second conjunct theorem Th22: for N being meet-continuous Lawson (complete TopLattice) st InclPoset sigma N is continuous holds N is topological_semilattice proof let N be meet-continuous Lawson (complete TopLattice) such that A1: InclPoset sigma N is continuous; let g be map of [:N,N qua TopSpace:], N such that A2: g = inf_op N; consider NN being Lawson correct TopAugmentation of [:N,N:]; A3: the RelStr of NN = the RelStr of [:N,N:] by YELLOW_9:def 4; then reconsider h = inf_op N as map of NN, N; A4: the RelStr of N = the RelStr of N; A5: h is infs-preserving proof let X be Subset of NN; reconsider X1 = X as Subset of [:N,N:] by A3; inf_op N preserves_inf_of X1 by WAYBEL_0:def 32; hence h preserves_inf_of X by A3,A4,WAYBEL_0:65; end; then A6: h is SemilatticeHomomorphism of NN, N by WAYBEL21:5; h is directed-sups-preserving proof let X be Subset of NN; assume X is non empty directed; then reconsider X1 = X as non empty directed Subset of [:N,N:] by A3,WAYBEL_0:3; inf_op N preserves_sup_of X1 by WAYBEL_0:def 37; hence h preserves_sup_of X by A3,A4,WAYBEL_0:65; end; then A7: h is continuous by A5,A6,WAYBEL21:46; A8: the TopStruct of N = the TopStruct of N; N is TopAugmentation of N by YELLOW_9:44; then the TopStruct of NN = [:N,N qua TopSpace:] by A1,Th20; hence g is continuous by A2,A7,A8,YELLOW12:36; end; Lm3: now let S, T, x1, x2 be set such that A1: x1 in S & x2 in T; A2:dom <:pr2(S,T),pr1(S,T):> = dom pr2(S,T) /\ dom pr1(S,T) by FUNCT_3:def 8 .= dom pr2(S,T) /\ [:S,T:] by FUNCT_3:def 5 .= [:S,T:] /\ [:S,T:] by FUNCT_3:def 6 .= [:S,T:]; [x1,x2] in [:S,T:] by A1,ZFMISC_1:106; hence <:pr2(S,T),pr1(S,T):>. [x1,x2] = [pr2(S,T). [x1,x2],pr1(S,T). [x1,x2]] by A2,FUNCT_3:def 8 .= [x2,pr1(S,T). [x1,x2]] by A1,FUNCT_3:def 6 .= [x2,x1] by A1,FUNCT_3:def 5; end; :: Proposition 2.4, p. 153 theorem for N being meet-continuous Lawson (complete TopLattice) st InclPoset sigma N is continuous holds N is Hausdorff iff for X being Subset of [:N,N qua TopSpace:] st X = the InternalRel of N holds X is closed proof let N be meet-continuous Lawson (complete TopLattice) such that A1: InclPoset sigma N is continuous; A2: [:the carrier of N,the carrier of N:] = the carrier of [:N,N qua TopSpace:] by BORSUK_1:def 5; hereby assume A3: N is Hausdorff; let X be Subset of [:N,N qua TopSpace:] such that A4: X = the InternalRel of N; set INF = inf_op N, f = <:pr1(the carrier of N,the carrier of N),INF:>; A5: the carrier of [:N,N:] = [:the carrier of N,the carrier of N:] by YELLOW_3:def 2; then f is Function of [:the carrier of N,the carrier of N:], [:the carrier of N,the carrier of N:] by FUNCT_3:78; then reconsider f as map of [:N,N qua TopSpace:], [:N,N qua TopSpace:] by A2; A6: for x, y being Element of N holds f. [x,y] = [x, x "/\" y] proof let x, y be Element of N; A7: dom (pr1(the carrier of N,the carrier of N)) = [:the carrier of N,the carrier of N:] by FUNCT_2:def 1; A8: dom INF = [:the carrier of N,the carrier of N:] by A5,FUNCT_2:def 1; [x,y] in [:the carrier of N,the carrier of N:] by ZFMISC_1:106; hence f. [x,y] = [pr1(the carrier of N,the carrier of N). [x,y],INF. [x,y]] by A7,A8,FUNCT_3:69 .= [x, INF. [x,y]] by FUNCT_3:def 5 .= [x, x "/\" y] by WAYBEL_2:def 4; end; id the carrier of N c= [:the carrier of N,the carrier of N:] by RELSET_1:28; then reconsider D = id the carrier of N as Subset of [:N,N qua TopSpace:] by A2; A9: D is closed by A3,YELLOW12:46; reconsider INF as map of [:N,N qua TopSpace:], N by A2,A5; N is topological_semilattice by A1,Th22; then A10: INF is continuous by YELLOW13:def 5; pr1(the carrier of N,the carrier of N) is continuous map of [:N,N qua TopSpace:],N by YELLOW12:39; then A11: f is continuous by A10,YELLOW12:41; X = f"D proof hereby let a be set; assume A12: a in X; then consider s, t being set such that A13: s in the carrier of N & t in the carrier of N & a = [s,t] by A4,ZFMISC_1:def 2; reconsider s, t as Element of N by A13; s <= t by A4,A12,A13,ORDERS_1:def 9; then s "/\" t = s by YELLOW_0:25; then f. [s,t] = [s,s] by A6; then A14: f.a in D by A13,RELAT_1:def 10; dom f = the carrier of [:N,N qua TopSpace:] by FUNCT_2:def 1; then a in dom f by A2,A13,ZFMISC_1:106; hence a in f"D by A14,FUNCT_1:def 13; end; let a be set; assume A15: a in f"D; then A16: a in dom f & f.a in D by FUNCT_1:def 13; consider s, t being set such that A17: s in the carrier of N & t in the carrier of N & a = [s,t] by A2,A15,ZFMISC_1:def 2; reconsider s, t as Element of N by A17; f.a = [s, s "/\" t] by A6,A17; then s = s "/\" t by A16,RELAT_1:def 10; then s <= t by YELLOW_0:25; hence a in X by A4,A17,ORDERS_1:def 9; end; hence X is closed by A9,A11,PRE_TOPC:def 12; end; assume A18: for X being Subset of [:N,N qua TopSpace:] st X = the InternalRel of N holds X is closed; A19: id the carrier of N = (the InternalRel of N) /\ the InternalRel of N~ proof thus id the carrier of N c= (the InternalRel of N) /\ the InternalRel of N~ by YELLOW12:22; thus thesis by YELLOW12:23; end; for A being Subset of [:N,N qua TopSpace:] st A = id the carrier of N holds A is closed proof let A be Subset of [:N,N qua TopSpace:] such that A20: A = id the carrier of N; A21: N~ = RelStr(#the carrier of N, (the InternalRel of N)~#) by LATTICE3:def 5; then reconsider X = the InternalRel of N, Y = the InternalRel of N~ as Subset of [:N,N qua TopSpace:] by BORSUK_1:def 5; reconsider X, Y as Subset of [:N,N qua TopSpace:] ; reconsider f = <:pr2(the carrier of N,the carrier of N), pr1(the carrier of N,the carrier of N):> as continuous map of [:N,N qua TopSpace:], [:N,N qua TopSpace:] by YELLOW12:42; A22: dom f = [:the carrier of N,the carrier of N:] by YELLOW12:4; A23: X is closed by A18; A24: f.:X = Y proof thus f.:X c= Y proof let y be set; assume y in f.:X; then consider x being set such that A25: x in dom f & x in X & y = f.x by FUNCT_1:def 12; consider x1, x2 being set such that A26: x1 in the carrier of N & x2 in the carrier of N & x = [x1,x2] by A25,ZFMISC_1:def 2; f.x = [x2,x1] by A26,Lm3; hence y in Y by A21,A25,A26,RELAT_1:def 7; end; let y be set; assume A27: y in Y; then consider y1, y2 being set such that A28: y1 in the carrier of N & y2 in the carrier of N & y = [y1,y2] by A21,ZFMISC_1:def 2; A29: [y2,y1] in X by A21,A27,A28,RELAT_1:def 7; f. [y2,y1] = y by A28,Lm3; hence y in f.:X by A22,A29,FUNCT_1:def 12; end; f is_homeomorphism by YELLOW12:43; then Y is closed by A23,A24,TOPS_2:72; hence A is closed by A19,A20,A23,TOPS_1:35; end; hence N is Hausdorff by YELLOW12:46; end; :: Definition 2.5, p. 154 definition let N be non empty reflexive RelStr, X be Subset of N; func X^0 -> Subset of N equals :Def1: { u where u is Element of N : for D being non empty directed Subset of N st u <= sup D holds X meets D }; coherence proof defpred P[Element of N] means for D being non empty directed Subset of N st $1 <= sup D holds X meets D; thus {u where u is Element of N: P[u]} is Subset of N from RelStrSubset; end; end; definition let N be non empty reflexive antisymmetric RelStr, X be empty Subset of N; cluster X^0 -> empty; coherence proof A1: X^0 = { u where u is Element of N : for D being non empty directed Subset of N st u <= sup D holds X meets D } by Def1; X^0 = {} proof thus X^0 c= {} proof let a be set such that A2: a in X^0 and not a in {}; consider u being Element of N such that A3: a = u & for D being non empty directed Subset of N st u <= sup D holds X meets D by A1,A2; reconsider D = {u} as non empty directed Subset of N by WAYBEL_0:5; A4: u <= sup D by YELLOW_0:39; X misses D by XBOOLE_1:65; hence contradiction by A3,A4; end; thus thesis by XBOOLE_1:2; end; hence thesis; end; end; theorem for N being non empty reflexive RelStr, A, J being Subset of N st A c= J holds A^0 c= J^0 proof let N be non empty reflexive RelStr, A, J be Subset of N such that A1: A c= J; A2: A^0 = { u where u is Element of N : for D being non empty directed Subset of N st u <= sup D holds A meets D } by Def1; A3: J^0 = { u where u is Element of N : for D being non empty directed Subset of N st u <= sup D holds J meets D } by Def1; let a be set; assume a in A^0; then consider u being Element of N such that A4: a = u & for D being non empty directed Subset of N st u <= sup D holds A meets D by A2; now let D be non empty directed Subset of N; assume u <= sup D; then A meets D by A4; hence J meets D by A1,XBOOLE_1:63; end; hence a in J^0 by A3,A4; end; :: Remark 2.6 (i), p. 154 theorem Th25: for N being non empty reflexive RelStr, x being Element of N holds (uparrow x)^0 = wayabove x proof let N be non empty reflexive RelStr, x be Element of N; A1: (uparrow x)^0 = { u where u is Element of N : for D being non empty directed Subset of N st u <= sup D holds (uparrow x) meets D } by Def1; thus (uparrow x)^0 c= wayabove x proof let a be set; assume a in (uparrow x)^0; then consider u being Element of N such that A2: a = u & for D being non empty directed Subset of N st u <= sup D holds (uparrow x) meets D by A1; u >> x proof let D be non empty directed Subset of N; assume u <= sup D; then (uparrow x) meets D by A2; then consider d being set such that A3: d in (uparrow x) /\ D by XBOOLE_0:4; reconsider d as Element of N by A3; take d; thus d in D by A3,XBOOLE_0:def 3; d in uparrow x by A3,XBOOLE_0:def 3; hence x <= d by WAYBEL_0:18; end; hence a in wayabove x by A2,WAYBEL_3:8; end; let a be set; assume A4: a in wayabove x; then reconsider b = a as Element of N; now let D be non empty directed Subset of N such that A5: b <= sup D; b >> x by A4,WAYBEL_3:8; then consider d being Element of N such that A6: d in D & x <= d by A5,WAYBEL_3:def 1; d in uparrow x by A6,WAYBEL_0:18; hence (uparrow x) meets D by A6,XBOOLE_0:3; end; hence a in (uparrow x)^0 by A1; end; :: Remark 2.6 (ii), p. 154 theorem Th26: for N being Scott TopLattice, X being upper Subset of N holds Int X c= X^0 proof let N be Scott TopLattice, X be upper Subset of N; let x be set; assume A1: x in Int X; then reconsider y = x as Element of N; A2: X^0 = { u where u is Element of N : for D being non empty directed Subset of N st u <= sup D holds X meets D } by Def1; now let D be non empty directed Subset of N such that A3: y <= sup D; A4: Int X c= X by TOPS_1:44; A5: Int X is upper inaccessible by WAYBEL11:def 4; then sup D in Int X by A1,A3,WAYBEL_0:def 20; then D meets Int X by A5,WAYBEL11:def 1; hence X meets D by A4,XBOOLE_1:63; end; hence x in X^0 by A2; end; :: Lemma 2.7 (i), p. 154 theorem Th27: for N being non empty reflexive RelStr, X, Y being Subset of N holds (X^0) \/ (Y^0) c= (X \/ Y)^0 proof let N be non empty reflexive RelStr, X, Y be Subset of N; let a be set; assume A1: a in (X^0) \/ (Y^0); then reconsider b = a as Element of N; A2: X^0 = { x where x is Element of N : for D being non empty directed Subset of N st x <= sup D holds X meets D } by Def1; A3: Y^0 = { y where y is Element of N : for D being non empty directed Subset of N st y <= sup D holds Y meets D } by Def1; A4: (X \/ Y)^0 = { xy where xy is Element of N : for D being non empty directed Subset of N st xy <= sup D holds (X \/ Y) meets D } by Def1; now let D be non empty directed Subset of N such that A5: b <= sup D; now per cases by A1,XBOOLE_0:def 2; suppose a in X^0; then consider x being Element of N such that A6: a = x & for D being non empty directed Subset of N st x <= sup D holds X meets D by A2; X meets D by A5,A6; then A7: X /\ D <> {} by XBOOLE_0:def 7; X /\ D c= X /\ D \/ Y /\ D by XBOOLE_1:7; then X /\ D \/ Y /\ D <> {} by A7,XBOOLE_1:3; hence (X \/ Y) /\ D <> {} by XBOOLE_1:23; suppose a in Y^0; then consider y being Element of N such that A8: a = y & for D being non empty directed Subset of N st y <= sup D holds Y meets D by A3; Y meets D by A5,A8; then A9: Y /\ D <> {} by XBOOLE_0:def 7; Y /\ D c= X /\ D \/ Y /\ D by XBOOLE_1:7; then X /\ D \/ Y /\ D <> {} by A9,XBOOLE_1:3; hence (X \/ Y) /\ D <> {} by XBOOLE_1:23; end; hence (X \/ Y) meets D by XBOOLE_0:def 7; end; hence a in (X \/ Y)^0 by A4; end; :: Lemma 2.7 (ii), p. 154 theorem Th28: for N being meet-continuous LATTICE, X, Y being upper Subset of N holds (X^0) \/ (Y^0) = (X \/ Y)^0 proof let N be meet-continuous LATTICE, X, Y be upper Subset of N; thus (X^0) \/ (Y^0) c= (X \/ Y)^0 by Th27; assume not (X \/ Y)^0 c= (X^0) \/ (Y^0); then consider s being set such that A1: s in (X \/ Y)^0 and A2: not s in (X^0) \/ (Y^0) by TARSKI:def 3; A3: not s in X^0 & not s in Y^0 by A2,XBOOLE_0:def 2; reconsider s as Element of N by A1; X^0 = { x where x is Element of N : for D being non empty directed Subset of N st x <= sup D holds X meets D } by Def1; then consider D being non empty directed Subset of N such that A4: s <= sup D & X misses D by A3; Y^0 = { y where y is Element of N : for D being non empty directed Subset of N st y <= sup D holds Y meets D } by Def1; then consider E being non empty directed Subset of N such that A5: s <= sup E & Y misses E by A3; (X \/ Y)^0 = { xy where xy is Element of N : for D being non empty directed Subset of N st xy <= sup D holds (X \/ Y) meets D } by Def1; then consider xy being Element of N such that A6: s = xy & for D being non empty directed Subset of N st xy <= sup D holds (X \/ Y) meets D by A1; s "/\" s = s by YELLOW_0:25; then s <= (sup D) "/\" (sup E) by A4,A5,YELLOW_3:2; then s <= sup (D "/\" E) by WAYBEL_2:51; then (X \/ Y) meets (D"/\"E) by A6; then A7: (X \/ Y) /\ (D"/\"E) <> {} by XBOOLE_0:def 7; X misses (D "/\" E) & Y misses (D "/\" E) by A4,A5,YELLOW12:21; then X /\ (D "/\" E) = {} & Y /\ (D "/\" E) = {} by XBOOLE_0:def 7; then X /\ (D"/\"E) \/ Y /\ (D"/\"E) = {}; hence contradiction by A7,XBOOLE_1:23; end; :: Lemma 2.8, p. 154 theorem Th29: for S being meet-continuous Scott TopLattice, F being finite Subset of S holds Int uparrow F c= union { wayabove x where x is Element of S : x in F } proof let S be meet-continuous Scott TopLattice, F be finite Subset of S; defpred P[set] means ex UU being Subset-Family of S st UU = {uparrow x where x is Element of S : x in $1} & (union UU)^0 = union { (uparrow x)^0 where x is Element of S : x in $1 }; A1: F is finite; A2: P[{}] proof {} is Subset of bool the carrier of S by XBOOLE_1:2; then {} is Subset-Family of S by SETFAM_1:def 7; then reconsider UU = {} as Subset-Family of S; take UU; thus UU = {uparrow x where x is Element of S : x in {}} proof deffunc F(Element of S) = uparrow $1; {F(x) where x is Element of S : x in {}} = {} from EmptySch; hence thesis; end; deffunc F(Element of S) = (uparrow $1)^0; A3: {F(x) where x is Element of S : x in {}} = {} from EmptySch; reconsider K = union UU as empty Subset of S by ZFMISC_1:2; K^0 is empty; hence thesis by A3; end; A4: for b, J being set st b in F & J c= F & P[J] holds P[J \/ {b}] proof let b, J be set; assume A5: b in F & J c= F; assume P[J]; then consider UU being Subset-Family of S such that A6: UU = {uparrow x where x is Element of S : x in J} and A7: (union UU)^0 = union {(uparrow x)^0 where x is Element of S : x in J}; reconsider bb = b as Element of S by A5; UU \/ {uparrow bb} is Subset-Family of S proof UU \/ {uparrow bb} c= bool the carrier of S proof let a be set; assume a in UU \/ {uparrow bb}; then a in UU or a in {uparrow bb} by XBOOLE_0:def 2; then a in UU or a = uparrow bb by TARSKI:def 1; hence a in bool the carrier of S; end; hence thesis by SETFAM_1:def 7; end; then reconsider I = UU \/ {uparrow bb} as Subset-Family of S ; take I; thus I = {uparrow x where x is Element of S : x in J \/ {b}} proof thus I c= {uparrow x where x is Element of S : x in J \/ {b}} proof let a be set such that A8: a in I; per cases by A8,XBOOLE_0:def 2; suppose a in UU; then consider x being Element of S such that A9: a = uparrow x & x in J by A6; J c= J \/ {b} by XBOOLE_1:7; hence thesis by A9; suppose a in {uparrow bb}; then A10: a = uparrow bb by TARSKI:def 1; b in {b} & {b} c= J \/ {b} by TARSKI:def 1,XBOOLE_1:7; hence thesis by A10; end; let a be set; assume a in {uparrow x where x is Element of S : x in J \/ {b}}; then consider x being Element of S such that A11: a = uparrow x & x in J \/ {b}; per cases by A11,XBOOLE_0:def 2; suppose x in J; then A12: uparrow x in UU by A6; UU c= UU \/ {uparrow bb} by XBOOLE_1:7; hence thesis by A11,A12; suppose x in {b}; then A13: x = b by TARSKI:def 1; A14: a in {uparrow x} by A11,TARSKI:def 1; {uparrow bb} c= UU \/ {uparrow bb} by XBOOLE_1:7; hence thesis by A13,A14; end; for X being Subset of S st X in UU holds X is upper proof let X be Subset of S; assume X in UU; then consider x being Element of S such that A15: X = uparrow x & x in J by A6; thus X is upper by A15; end; then A16: union UU is upper by WAYBEL_0:28; A17: (union UU) \/ uparrow bb = union I proof thus (union UU) \/ uparrow bb c= union I proof let a be set such that A18: a in (union UU) \/ uparrow bb; per cases by A18,XBOOLE_0:def 2; suppose a in union UU; then consider A being set such that A19: a in A & A in UU by TARSKI:def 4; UU c= I by XBOOLE_1:7; hence a in union I by A19,TARSKI:def 4; suppose A20: a in uparrow bb; A21: {uparrow bb} c= UU \/ {uparrow bb} by XBOOLE_1:7; uparrow bb in {uparrow bb} by TARSKI:def 1; hence a in union I by A20,A21,TARSKI:def 4; end; let a be set; assume a in union I; then consider A being set such that A22: a in A & A in I by TARSKI:def 4; per cases by A22,XBOOLE_0:def 2; suppose A in UU; then A c= union UU by ZFMISC_1:92; then A23: a in union UU by A22; union UU c= (union UU) \/ uparrow bb by XBOOLE_1:7; hence a in (union UU) \/ uparrow bb by A23; suppose A in {uparrow bb}; then A24: A = uparrow bb by TARSKI:def 1; uparrow bb c= (union UU) \/ uparrow bb by XBOOLE_1:7; hence a in (union UU) \/ uparrow bb by A22,A24; end; (union {(uparrow x)^0 where x is Element of S : x in J}) \/ ((uparrow bb)^0) = union {(uparrow x)^0 where x is Element of S : x in J \/ {b}} proof {(uparrow x)^0 where x is Element of S : x in J} c= {(uparrow x)^0 where x is Element of S : x in J \/ {b}} proof let a be set; assume a in {(uparrow x)^0 where x is Element of S : x in J}; then consider y being Element of S such that A25: a = (uparrow y)^0 & y in J; J c= J \/ {b} by XBOOLE_1:7; hence a in {(uparrow x)^0 where x is Element of S : x in J \/ {b}} by A25; end; then A26: union {(uparrow x)^0 where x is Element of S : x in J} c= union {(uparrow x)^0 where x is Element of S : x in J \/ {b}} by ZFMISC_1:95; A27: b in {b} by TARSKI:def 1; {b} c= J \/ {b} by XBOOLE_1:7; then (uparrow bb)^0 in {(uparrow x)^0 where x is Element of S : x in J \/ {b}} by A27; then (uparrow bb)^0 c= union {(uparrow x)^0 where x is Element of S : x in J \/ {b}} by ZFMISC_1:92; hence (union {(uparrow x)^0 where x is Element of S : x in J}) \/ ((uparrow bb)^0) c= union {(uparrow x)^0 where x is Element of S : x in J \/ {b}} by A26,XBOOLE_1:8; let a be set; assume a in union {(uparrow x)^0 where x is Element of S : x in J \/ {b}}; then consider A being set such that A28: a in A & A in {(uparrow x)^0 where x is Element of S : x in J \/ {b}} by TARSKI:def 4; consider y being Element of S such that A29: A = (uparrow y)^0 & y in J \/ {b} by A28; per cases by A29,XBOOLE_0:def 2; suppose y in J; then (uparrow y)^0 in {(uparrow x)^0 where x is Element of S : x in J} ; then A30: a in union {(uparrow x)^0 where x is Element of S : x in J} by A28,A29,TARSKI:def 4; union {(uparrow x)^0 where x is Element of S : x in J} c= (union {(uparrow x)^0 where x is Element of S : x in J}) \/ ((uparrow bb)^0) by XBOOLE_1:7; hence thesis by A30; suppose y in {b}; then A31: y = b by TARSKI:def 1; (uparrow bb)^0 c= (union {(uparrow x)^0 where x is Element of S : x in J}) \/ ((uparrow bb)^0) by XBOOLE_1:7; hence thesis by A28,A29,A31; end; hence (union I)^0 = union { (uparrow x)^0 where x is Element of S : x in J \/ {b} } by A7,A16,A17,Th28; end; P[F] from Finite(A1,A2,A4); then consider UU being Subset-Family of S such that A32: UU = {uparrow x where x is Element of S : x in F} & (union UU)^0 = union { (uparrow x)^0 where x is Element of S : x in F }; {(uparrow x)^0 where x is Element of S : x in F} = {wayabove x where x is Element of S : x in F} proof thus {(uparrow x)^0 where x is Element of S : x in F} c= {wayabove x where x is Element of S : x in F} proof let a be set; assume a in {(uparrow x)^0 where x is Element of S : x in F}; then consider x being Element of S such that A33: a = (uparrow x)^0 & x in F; (uparrow x)^0 = wayabove x by Th25; hence thesis by A33; end; let a be set; assume a in {wayabove x where x is Element of S : x in F}; then consider x being Element of S such that A34: a = wayabove x & x in F; (uparrow x)^0 = wayabove x by Th25; hence thesis by A34; end; then (uparrow F)^0 = union {wayabove x where x is Element of S : x in F} by A32,YELLOW_9:4; hence Int uparrow F c= union {wayabove x where x is Element of S : x in F} by Th26; end; :: Theorem 2.9, p. 154 theorem Th30: for N being Lawson (complete TopLattice) holds N is continuous iff N is meet-continuous Hausdorff proof let N be Lawson (complete TopLattice); hereby assume N is continuous; then reconsider L1 = N as continuous lower-bounded Lawson (complete TopLattice); L1 is meet-continuous; hence N is meet-continuous Hausdorff; end; assume A1: N is meet-continuous Hausdorff; thus A2: for x being Element of N holds waybelow x is non empty directed; thus N is up-complete; for x, y being Element of N st not x <= y ex u being Element of N st u << x & not u <= y proof let x, y be Element of N such that A3: not x <= y; consider S being Scott TopAugmentation of N; A4: the RelStr of S = the RelStr of N by YELLOW_9:def 4; reconsider J = {O\uparrow F where O, F is Subset of N: O in sigma N & F is finite} as Basis of N by WAYBEL19:32; x "/\" y <> x by A3,YELLOW_0:23; then consider W, V being Subset of N such that A5: W is open and A6: V is open and A7: x in W & x "/\" y in V & W misses V by A1,COMPTS_1:def 4; V = union {G where G is Subset of N: G in J & G c= V} by A6,YELLOW_8:18 ; then consider K being set such that A8: x "/\" y in K & K in {G where G is Subset of N: G in J & G c= V} by A7,TARSKI:def 4; consider V1 being Subset of N such that A9: K = V1 & V1 in J & V1 c= V by A8; consider U2, F being Subset of N such that A10: V1 = U2\uparrow F and A11: U2 in sigma N and A12: F is finite by A9; reconsider U1 = U2 as Subset of S by A4; U2 in sigma S by A4,A11,YELLOW_9:52; then A13: U1 is open by WAYBEL14:24; reconsider WU1 = W /\ U2 as Subset of N; WU1 c= uparrow F proof let w be set; assume A14: w in WU1 & not w in uparrow F; then A15: w in W by XBOOLE_0:def 3; A16: w in WU1 \ uparrow F by A14,XBOOLE_0:def 4; A17: W misses V1 by A7,A9,XBOOLE_1:63; W /\ U1 c= U1 by XBOOLE_1:17; then WU1 \ uparrow F c= U1 \ uparrow F by XBOOLE_1:33; hence contradiction by A10,A15,A16,A17,XBOOLE_0:3; end; then WU1 is_coarser_than uparrow F by WAYBEL12:20; then A18: uparrow WU1 c= uparrow F by YELLOW12:28; reconsider W1 = WU1 as Subset of S by A4; reconsider F1 = F as finite Subset of S by A4,A12; S is meet-continuous by A1,A4,YELLOW12:14; then A19: Int uparrow F1 c= union { wayabove u where u is Element of S : u in F1 } by Th29; A20: uparrow W1 = uparrow WU1 & uparrow F1 = uparrow F by A4,WAYBEL_0:13; reconsider x1 = x, y1 = y as Element of S by A4; A21: ex_inf_of {x1,y1},S by YELLOW_0:21; x "/\" y = inf {x,y} by YELLOW_0:40 .= "/\"({x1,y1},S) by A4,A21,YELLOW_0:27 .= x1 "/\" y1 by YELLOW_0:40; then A22: x1 "/\" y1 in U1 by A8,A9,A10,XBOOLE_0:def 4; A23: x1 "/\" y1 <= x1 by YELLOW_0:23; U1 is upper by A13,WAYBEL11:def 4; then x1 in U1 by A22,A23,WAYBEL_0:def 20; then A24: x in W1 by A7,XBOOLE_0:def 3; W1 c= uparrow W1 by WAYBEL_0:16; then A25: x in uparrow W1 by A24; N is Lawson correct TopAugmentation of S by A4,YELLOW_9:def 4; then U2 is open by A13,WAYBEL19:37; then WU1 is open by A5,TOPS_1:38; then uparrow W1 is open by A1,Th15; then uparrow W1 c= Int uparrow F1 by A18,A20,TOPS_1:56; then x in Int uparrow F1 by A25; then consider A being set such that A26: x in A & A in { wayabove u where u is Element of S : u in F1 } by A19,TARSKI:def 4; consider u being Element of S such that A27: A = wayabove u & u in F1 by A26; reconsider u1 = u as Element of N by A4; A28: wayabove u1 = wayabove u by A4,YELLOW12:13; A29: for N being Semilattice, x, y being Element of N st ex u being Element of N st u << x & not u <= x "/\" y ex u being Element of N st u << x & not u <= y proof let N be Semilattice, x, y be Element of N; given u being Element of N such that A30: u << x and A31: not u <= x "/\" y; take u; thus u << x by A30; assume A32: u <= y; u <= x by A30,WAYBEL_3:1; then u "/\" u <= x "/\" y by A32,YELLOW_3:2; hence contradiction by A31,YELLOW_0:25; end; now take u1; thus u1 << x by A26,A27,A28,WAYBEL_3:8; uparrow u1 c= uparrow F by A27,YELLOW12:30; then not x "/\" y in uparrow u1 by A8,A9,A10,XBOOLE_0:def 4; hence not u1 <= x "/\" y by WAYBEL_0:18; end; then consider u2 being Element of N such that A33: u2 << x & not u2 <= y by A29; take u2; thus thesis by A33; end; hence N is satisfying_axiom_of_approximation by A2,WAYBEL_3:24; end; definition cluster continuous Lawson -> Hausdorff (complete TopLattice); coherence by Th30; cluster meet-continuous Lawson Hausdorff -> continuous (complete TopLattice); coherence by Th30; end; :: Definition 2.10, p. 155 definition let N be non empty TopRelStr; attr N is with_small_semilattices means for x being Point of N ex J being basis of x st for A being Subset of N st A in J holds subrelstr A is meet-inheriting; attr N is with_compact_semilattices means for x being Point of N ex J being basis of x st for A being Subset of N st A in J holds subrelstr A is meet-inheriting & A is compact; attr N is with_open_semilattices means :Def4: for x being Point of N ex J being Basis of x st for A being Subset of N st A in J holds subrelstr A is meet-inheriting; end; definition cluster with_open_semilattices -> with_small_semilattices (non empty TopSpace-like TopRelStr); coherence proof let N be non empty TopSpace-like TopRelStr; assume A1: for x being Point of N ex J being Basis of x st for A being Subset of N st A in J holds subrelstr A is meet-inheriting; let x be Point of N; consider J being Basis of x such that A2: for A being Subset of N st A in J holds subrelstr A is meet-inheriting by A1; reconsider J as basis of x by YELLOW13:23; take J; thus thesis by A2; end; cluster with_compact_semilattices -> with_small_semilattices (non empty TopSpace-like TopRelStr); coherence proof let N be non empty TopSpace-like TopRelStr; assume A3: for x being Point of N ex J being basis of x st for A being Subset of N st A in J holds subrelstr A is meet-inheriting & A is compact; let x be Point of N; consider J being basis of x such that A4: for A being Subset of N st A in J holds subrelstr A is meet-inheriting & A is compact by A3; take J; thus thesis by A4; end; cluster anti-discrete -> with_small_semilattices with_open_semilattices (non empty TopRelStr); coherence proof let T be non empty TopRelStr; assume T is anti-discrete; then reconsider W = T as anti-discrete non empty TopRelStr; set J = {the carrier of W}; A5: now let A be Subset of W; assume A in J; then A6: A = the carrier of W by TARSKI:def 1 .= [#]W by PRE_TOPC:12; subrelstr [#]W is infs-inheriting; then reconsider K = subrelstr A as infs-inheriting SubRelStr of T by A6; K is meet-inheriting; hence subrelstr A is meet-inheriting; end; A7: W is with_small_semilattices proof let x be Point of W; reconsider J as basis of x by YELLOW13:21; take J; let A be Subset of W; assume A in J; hence subrelstr A is meet-inheriting by A5; end; W is with_open_semilattices proof let x be Point of W; reconsider J as Basis of x by YELLOW13:13; take J; let A be Subset of W; assume A in J; hence subrelstr A is meet-inheriting by A5; end; hence thesis by A7; end; cluster reflexive trivial TopSpace-like -> with_compact_semilattices (non empty TopRelStr); coherence proof let T be non empty TopRelStr; assume T is reflexive trivial TopSpace-like; then reconsider W = T as reflexive trivial non empty TopSpace-like TopRelStr; W is with_compact_semilattices proof let x be Point of W; reconsider J = {the carrier of W} as basis of x by YELLOW13:21; take J; let A be Subset of W; assume A in J; then A8: A = the carrier of W by TARSKI:def 1 .= [#]W by PRE_TOPC:12; subrelstr [#]W is infs-inheriting; then reconsider K = subrelstr A as infs-inheriting SubRelStr of T by A8; K is meet-inheriting; hence subrelstr A is meet-inheriting; thus A is compact by A8; end; hence thesis; end; end; definition cluster strict trivial lower TopLattice; existence proof consider T being strict trivial TopLattice; take T; thus thesis; end; end; theorem Th31: for N being topological_semilattice (with_infima TopPoset), C being Subset of N st subrelstr C is meet-inheriting holds subrelstr Cl C is meet-inheriting proof let N be topological_semilattice (with_infima TopPoset), C be Subset of N such that A1: subrelstr C is meet-inheriting; set A = Cl C, S = subrelstr A; let x, y be Element of N such that A2: x in the carrier of S & y in the carrier of S & ex_inf_of {x,y},N; A3: the carrier of S = A by YELLOW_0:def 15; for V being a_neighborhood of x "/\" y holds V meets C proof let V be a_neighborhood of x "/\" y; set NN = [:N,N qua TopSpace:]; A4: the carrier of NN = [:the carrier of N,the carrier of N:] by BORSUK_1:def 5; the carrier of [:N,N:] = [:the carrier of N,the carrier of N:] by YELLOW_3:def 2; then reconsider f = inf_op N as map of NN, N by A4; A5: f is continuous by YELLOW13:def 5; reconsider xy = [x,y] as Point of NN by A4,YELLOW_3:def 2; f.xy = x "/\" y by WAYBEL_2:def 4; then consider H being a_neighborhood of xy such that A6: f.:H c= V by A5,BORSUK_1:def 2; consider A being Subset-Family of NN such that A7: Int H = union A and A8: for e being set st e in A ex X1, Y1 being Subset of N st e = [:X1,Y1:] & X1 is open & Y1 is open by BORSUK_1:45; xy in union A by A7,CONNSP_2:def 1; then consider K being set such that A9: xy in K and A10: K in A by TARSKI:def 4; consider Ix, Iy being Subset of N such that A11: K = [:Ix,Iy:] & Ix is open & Iy is open by A8,A10; x in Ix & Ix = Int Ix by A9,A11,TOPS_1:55,ZFMISC_1:106; then reconsider Ix as a_neighborhood of x by CONNSP_2:def 1; Ix meets C by A2,A3,YELLOW_6:6; then consider ix being set such that A12: ix in Ix & ix in C by XBOOLE_0:3; y in Iy & Iy = Int Iy by A9,A11,TOPS_1:55,ZFMISC_1:106; then reconsider Iy as a_neighborhood of y by CONNSP_2:def 1; Iy meets C by A2,A3,YELLOW_6:6; then consider iy being set such that A13: iy in Iy & iy in C by XBOOLE_0:3; reconsider ix, iy as Element of N by A12,A13; now take a = ix "/\" iy; A14: f. [ix,iy] = ix "/\" iy by WAYBEL_2:def 4; A15: dom f = the carrier of [:N,N:] by FUNCT_2:def 1; [ix,iy] in K by A11,A12,A13,ZFMISC_1:106; then A16: [ix,iy] in Int H by A7,A10,TARSKI:def 4; Int H c= H by TOPS_1:44; then ix "/\" iy in f.:H by A14,A15,A16,FUNCT_1:def 12; hence a in V by A6; A17: the carrier of subrelstr C = C by YELLOW_0:def 15; ex_inf_of {ix,iy},N by YELLOW_0:21; then inf{ix,iy} in C by A1,A12,A13,A17,YELLOW_0:def 16; hence a in C by YELLOW_0:40; end; hence thesis by XBOOLE_0:3; end; then x "/\" y in Cl C by YELLOW_6:6; hence inf {x,y} in the carrier of S by A3,YELLOW_0:40; end; :: Theorem 2.11, p. 155 theorem Th32: for N being meet-continuous Lawson (complete TopLattice) for S being Scott TopAugmentation of N holds (for x being Point of S ex J being Basis of x st for W being Subset of S st W in J holds W is Filter of S) iff N is with_open_semilattices proof let N be meet-continuous Lawson (complete TopLattice), S be Scott TopAugmentation of N; A1: the RelStr of N = the RelStr of S by YELLOW_9:def 4; hereby assume A2: for x being Point of S ex J being Basis of x st for W being Subset of S st W in J holds W is Filter of S; thus N is with_open_semilattices proof let x be Point of N; A3: now let W be Subset of N such that A4: W is open and A5: x in W; reconsider BL = {O\uparrow F where O, F is Subset of N: O in sigma N & F is finite} as Basis of N by WAYBEL19:32; reconsider y = x as Point of S by A1; consider By being Basis of y such that A6: for A being Subset of S st A in By holds A is Filter of S by A2; W = union { G where G is Subset of N: G in BL & G c= W } by A4,YELLOW_8:18; then consider K being set such that A7: x in K & K in { G where G is Subset of N: G in BL & G c= W } by A5,TARSKI:def 4; consider G being Subset of N such that A8: K = G and A9: G in BL and A10: G c= W by A7; consider V, F being Subset of N such that A11: G = V \ uparrow F and A12: V in sigma N and A13: F is finite by A9; reconsider V as Subset of S by A1; A14: sigma N = sigma S by A1,YELLOW_9:52; then A15: V is open by A12,WAYBEL14:24; reconsider F as finite Subset of N by A13; y in V by A7,A8,A11,XBOOLE_0:def 4; then consider U1 being Subset of S such that A16: U1 in By and A17: U1 c= V by A15,YELLOW_8:22; reconsider U2 = U1 as Subset of N by A1; U1 is Filter of S by A6,A16; then reconsider U2 as Filter of N by A1,WAYBEL_0:4,25; U2 \ uparrow F is Subset of N; then reconsider IT = U1 \ uparrow F as Subset of N; take U2, F, IT; thus IT = U2 \ uparrow F; A18: y in U1 by A16,YELLOW_8:21; not x in uparrow F by A7,A8,A11,XBOOLE_0:def 4; hence x in IT by A18,XBOOLE_0:def 4; U1 is open by A16,YELLOW_8:21; then U1 in sigma S by WAYBEL14:24; then A19: IT in BL by A14; BL c= the topology of N by CANTOR_1:def 2; hence IT is open by A19,PRE_TOPC:def 5; IT c= G by A11,A17,XBOOLE_1:33; hence IT c= W by A10,XBOOLE_1:1; end; defpred P[set] means ex U1 being Filter of N, F being finite Subset of N, W1 being Subset of N st $1 = W1 & U1 \ uparrow F = $1 & x in $1 & W1 is open; consider SF being Subset-Family of N such that A20: for W being Subset of N holds W in SF iff P[W] from SubFamEx; reconsider SF as Subset-Family of N; SF is Basis of x proof thus SF c= the topology of N proof let a be set; assume A21: a in SF; then reconsider W = a as Subset of N; consider U1 being Filter of N, F being finite Subset of N, W1 being Subset of N such that A22: W1 = W and U1 \ uparrow F = W & x in W and A23: W1 is open by A20,A21; thus thesis by A22,A23,PRE_TOPC:def 5; end; for a being set st a in SF holds x in a proof let a be set; assume A24: a in SF; then reconsider W = a as Subset of N; consider U1 being Filter of N, F being finite Subset of N, W1 being Subset of N such that A25: W1 = W & U1 \ uparrow F = W & x in W & W1 is open by A20,A24; thus x in a by A25; end; hence x in Intersect SF by CANTOR_1:10; let W be Subset of N; assume W is open & x in W; then consider U2 being Filter of N, F being finite Subset of N, IT being Subset of N such that A26: IT = U2 \ uparrow F & x in IT & IT is open & IT c= W by A3; take IT; thus IT in SF & IT c= W by A20,A26; end; then reconsider SF as Basis of x; take SF; let W be Subset of N; assume W in SF; then consider U1 being Filter of N, F being finite Subset of N, W1 being Subset of N such that A27: W1 = W & U1 \ uparrow F = W & x in W & W1 is open by A20; set SW = subrelstr W; thus SW is meet-inheriting proof let a, b be Element of N such that A28: a in the carrier of SW & b in the carrier of SW & ex_inf_of {a,b},N; A29: the carrier of SW = W by YELLOW_0:def 15; then A30: a in U1 & b in U1 & not a in uparrow F & not b in uparrow F by A27,A28,XBOOLE_0:def 4; then consider z being Element of N such that A31: z in U1 & z <= a & z <= b by WAYBEL_0:def 2; z "/\" z <= a "/\" b by A31,YELLOW_3:2; then z <= a "/\" b by YELLOW_0:25; then A32: a "/\" b in U1 by A31,WAYBEL_0:def 20; for y being Element of N st y <= a "/\" b holds not y in F proof let y be Element of N such that A33: y <= a "/\" b; a "/\" b <= a by YELLOW_0:23; then y <= a by A33,ORDERS_1:26; hence not y in F by A30,WAYBEL_0:def 16; end; then not a "/\" b in uparrow F by WAYBEL_0:def 16; then a "/\" b in W by A27,A32,XBOOLE_0:def 4; hence inf {a,b} in the carrier of SW by A29,YELLOW_0:40; end; end; end; assume A34: N is with_open_semilattices; let x be Point of S; reconsider y = x as Point of N by A1; consider J being Basis of y such that A35: for A being Subset of N st A in J holds subrelstr A is meet-inheriting by A34,Def4; reconsider J' = {uparrow A where A is Subset of N: A in J} as Basis of x by Th16; take J'; let W be Subset of S; assume W in J'; then consider V being Subset of N such that A36: W = uparrow V and A37: V in J; A38: x in V by A37,YELLOW_8:21; A39: V c= uparrow V by WAYBEL_0:16; subrelstr V is meet-inheriting by A35,A37; then V is filtered by YELLOW12:26; then uparrow V is filtered by WAYBEL_0:35; hence W is Filter of S by A1,A36,A38,A39,WAYBEL_0:4,25; end; :: Theorem 2.12, p. 155, r => l theorem Th33: for N being Lawson (complete TopLattice) for S being Scott TopAugmentation of N for x being Element of N holds {inf A where A is Subset of S : x in A & A in sigma S} c= {inf J where J is Subset of N : x in J & J in lambda N} proof let N be Lawson (complete TopLattice), S be Scott TopAugmentation of N, x be Element of N; A1: the RelStr of N = the RelStr of S by YELLOW_9:def 4; set s = {inf A where A is Subset of S : x in A & A in sigma S}, l = {inf J where J is Subset of N : x in J & J in lambda N}; let k be set; assume k in s; then consider J being Subset of S such that A2: k = inf J & x in J & J in sigma S; reconsider A = J as Subset of N by A1; ex_inf_of A,N by YELLOW_0:17; then A3: inf A = inf J by A1,YELLOW_0:27; sigma N c= lambda N by Th10; then sigma S c= lambda N by A1,YELLOW_9:52; hence k in l by A2,A3; end; :: Theorem 2.12, p. 155 theorem Th34: for N being meet-continuous Lawson (complete TopLattice) for S being Scott TopAugmentation of N for x being Element of N holds {inf A where A is Subset of S : x in A & A in sigma S} = {inf J where J is Subset of N : x in J & J in lambda N} proof let N be meet-continuous Lawson (complete TopLattice), S be Scott TopAugmentation of N, x be Element of N; A1: the RelStr of N = the RelStr of S by YELLOW_9:def 4; set l = {inf A where A is Subset of N : x in A & A in lambda N}, s = {inf J where J is Subset of S : x in J & J in sigma S}; thus s c= l by Th33; let k be set; assume k in l; then consider A being Subset of N such that A2: k = inf A & x in A & A in lambda N; reconsider J = A as Subset of S by A1; A3: ex_inf_of J,S by YELLOW_0:17; then A4: inf A = inf J by A1,YELLOW_0:27 .= inf uparrow J by A3,WAYBEL_0:38; A5: J c= uparrow J by WAYBEL_0:16; A is open by A2,Th12; then uparrow J is open by Th15; then uparrow J in sigma S by WAYBEL14:24; hence k in s by A2,A4,A5; end; :: Theorem 2.13, p. 155, 1 <=> 2 theorem Th35: for N being meet-continuous Lawson (complete TopLattice) holds N is continuous iff N is with_open_semilattices & InclPoset sigma N is continuous proof let N be meet-continuous Lawson (complete TopLattice); consider S being Scott TopAugmentation of N; A1: the RelStr of N = the RelStr of S by YELLOW_9:def 4; then A2: sigma S = sigma N by YELLOW_9:52; hereby assume N is continuous; then A3: S is continuous by A1,YELLOW12:15; for x being Point of S ex J being Basis of x st for W being Subset of S st W in J holds W is Filter of S proof let x be Point of S; consider J being Basis of x such that A4: for W being Subset of S st W in J holds W is open filtered by A3,WAYBEL14:35; take J; let W be Subset of S; assume A5: W in J; then W is open by A4; hence W is Filter of S by A4,A5,WAYBEL11:def 4,YELLOW_8:21; end; hence N is with_open_semilattices by Th32; InclPoset sigma S is continuous by A3,WAYBEL14:36; hence InclPoset sigma N is continuous by A1,YELLOW_9:52; end; assume A6: N is with_open_semilattices & InclPoset sigma N is continuous; for x being Element of S ex J being Basis of x st for Y being Subset of S st Y in J holds Y is open filtered proof let x be Element of S; reconsider y = x as Element of N by A1; consider J being Basis of y such that A7: for A being Subset of N st A in J holds subrelstr A is meet-inheriting by A6,Def4; reconsider J' = {uparrow A where A is Subset of N: A in J} as Basis of x by Th16; take J'; let Y be Subset of S; assume A8: Y in J'; then consider A being Subset of N such that A9: Y = uparrow A and A10: A in J; subrelstr A is meet-inheriting by A7,A10; then A is filtered by YELLOW12:26; then uparrow A is filtered by WAYBEL_0:35; hence Y is open filtered by A1,A8,A9,WAYBEL_0:4,YELLOW_8:21; end; then for x being Element of S holds x = "\/" ({inf X where X is Subset of S : x in X & X in sigma S}, S) by A2,A6,WAYBEL14:37; then S is continuous by WAYBEL14:38; hence N is continuous by A1,YELLOW12:15; end; definition cluster continuous -> with_open_semilattices (Lawson complete TopLattice); coherence proof let N be Lawson complete TopLattice; assume N is continuous; then reconsider M = N as continuous Lawson complete TopLattice; M is with_open_semilattices by Th35; hence thesis; end; end; definition let N be continuous Lawson (complete TopLattice); cluster InclPoset sigma N -> continuous; coherence by Th35; end; :: Theorem 2.13, p. 155, 1 => 3 theorem for N being continuous Lawson (complete TopLattice) holds N is compact Hausdorff topological_semilattice with_open_semilattices proof let N be continuous Lawson (complete TopLattice); thus N is compact Hausdorff; InclPoset sigma N is continuous; hence N is topological_semilattice by Th22; thus N is with_open_semilattices; end; :: Theorem 2.13, p. 155, 3 => 3' theorem for N being Hausdorff topological_semilattice with_open_semilattices Lawson (complete TopLattice) holds N is with_compact_semilattices proof let N be Hausdorff topological_semilattice with_open_semilattices Lawson (complete TopLattice); let x be Point of N; consider BO being Basis of x such that A1: for A being Subset of N st A in BO holds subrelstr A is meet-inheriting by Def4; set BC = {Cl A where A is Subset of N: A in BO}; BC is Subset-Family of N proof BC c= bool the carrier of N proof let k be set; assume k in BC; then consider A being Subset of N such that A2: k = Cl A and A in BO; thus k in bool the carrier of N by A2; end; hence thesis by SETFAM_1:def 7; end; then reconsider BC as Subset-Family of N; BC is basis of x proof let S be a_neighborhood of x; x in Int S by CONNSP_2:def 1; then consider W being Subset of N such that A3: W in BO and A4: W c= Int S by YELLOW_8:22; A5: x in W & W is open by A3,YELLOW_8:21; then x in Int W by TOPS_1:55; then reconsider T = W as a_neighborhood of x by CONNSP_2:def 1; A6: Int S c= S by TOPS_1:44; per cases; suppose A7: W <> [#]N; x in W by A3,YELLOW_8:21; then {x} c= W by ZFMISC_1:37; then consider G being Subset of N such that A8: G is open and A9: {x} c= G and A10: Cl G c= W by A5,A7,CONNSP_2:26; x in G by A9,ZFMISC_1:37; then consider K being Subset of N such that A11: K in BO and A12: K c= G by A8,YELLOW_8:22; x in K & K is open by A11,YELLOW_8:21; then A13: x in Int K by TOPS_1:55; K c= Cl K by PRE_TOPC:48; then Int K c= Int Cl K by TOPS_1:48; then reconsider KK = Cl K as a_neighborhood of x by A13,CONNSP_2:def 1; take KK; thus KK in BC by A11; Cl K c= Cl G by A12,PRE_TOPC:49; then Cl K c= W by A10,XBOOLE_1:1; then KK c= Int S by A4,XBOOLE_1:1; hence KK c= S by A6,XBOOLE_1:1; suppose A14: W = [#]N; take T; Cl [#]N = [#]N by TOPS_1:27; hence T in BC by A3,A14; thus T c= S by A4,A6,XBOOLE_1:1; end; then reconsider BC as basis of x; take BC; let A be Subset of N; assume A in BC; then consider C being Subset of N such that A15: A = Cl C and A16: C in BO; subrelstr C is meet-inheriting by A1,A16; hence subrelstr A is meet-inheriting by A15,Th31; thus A is compact by A15,COMPTS_1:17; end; :: Theorem 2.13, p. 155, 3' => 4 theorem for N being meet-continuous Hausdorff Lawson (complete TopLattice), x being Element of N holds x = "\/"({inf V where V is Subset of N: x in V & V in lambda N},N) proof let N be meet-continuous Hausdorff Lawson (complete TopLattice), x be Element of N; consider S being Scott complete TopAugmentation of N; A1: the RelStr of S = the RelStr of N by YELLOW_9:def 4; then reconsider y = x as Element of S; A2: for y being Element of S ex J being Basis of y st for X being Subset of S st X in J holds X is open filtered by WAYBEL14:35; A3: ex_sup_of {inf X where X is Subset of S: y in X & X in sigma S}, S by YELLOW_0:17; InclPoset sigma S is continuous by WAYBEL14:36; hence x = "\/" ({inf X where X is Subset of S: y in X & X in sigma S}, S) by A2,WAYBEL14:37 .= "\/" ({inf X where X is Subset of S: x in X & X in sigma S}, N) by A1,A3,YELLOW_0:26 .= "\/" ({inf V where V is Subset of N: x in V & V in lambda N}, N) by Th34; end; :: Theorem 2.13, p. 155, 1 <=> 4 theorem for N being meet-continuous Lawson (complete TopLattice) holds N is continuous iff for x being Element of N holds x = "\/"({inf V where V is Subset of N: x in V & V in lambda N},N) proof let N be meet-continuous Lawson (complete TopLattice); consider S being complete Scott TopAugmentation of N; A1: the RelStr of S = the RelStr of N by YELLOW_9:def 4; hereby assume A2: N is continuous; let x be Element of N; A3: x is Element of S by A1; A4: S is continuous by A1,A2,YELLOW12:15; then A5: InclPoset sigma S is continuous by WAYBEL14:36; A6: ex_sup_of {inf X where X is Subset of S: x in X & X in sigma S}, N by YELLOW_0:17; for x being Element of S ex J being Basis of x st for Y being Subset of S st Y in J holds Y is open filtered by A4,WAYBEL14:35; hence x = "\/" ({inf X where X is Subset of S: x in X & X in sigma S}, S ) by A3,A5,WAYBEL14:37 .= "\/" ({inf X where X is Subset of S: x in X & X in sigma S}, N) by A1,A6,YELLOW_0:26 .= "\/"({inf V where V is Subset of N: x in V & V in lambda N},N) by Th34; end; assume A7: for x being Element of N holds x = "\/"({inf V where V is Subset of N: x in V & V in lambda N},N); now let x be Element of S; A8: x is Element of N by A1; A9: ex_sup_of {inf X where X is Subset of S: x in X & X in sigma S}, N by YELLOW_0:17; thus x = "\/"({inf V where V is Subset of N: x in V & V in lambda N},N) by A7,A8 .= "\/"({inf V where V is Subset of S: x in V & V in sigma S},N) by A8,Th34 .= "\/"({inf V where V is Subset of S: x in V & V in sigma S},S) by A1,A9,YELLOW_0:26; end; then S is continuous by WAYBEL14:38; hence thesis by A1,YELLOW12:15; end; :: Exercise 2.16, p. 156, 1 <=> 2 theorem Th40: for N being meet-continuous Lawson (complete TopLattice) holds N is algebraic iff N is with_open_semilattices & InclPoset sigma N is algebraic proof let N be meet-continuous Lawson (complete TopLattice); consider S being Scott TopAugmentation of N; A1: the RelStr of S = the RelStr of N by YELLOW_9:def 4; hereby assume A2: N is algebraic; then reconsider M = N as algebraic LATTICE; M is continuous; hence N is with_open_semilattices by Th35; S is algebraic by A1,A2,WAYBEL_8:17; then ex K being Basis of S st K = {uparrow x where x is Element of S: x in the carrier of CompactSublatt S} by WAYBEL14:42; then InclPoset sigma S is algebraic by WAYBEL14:43; hence InclPoset sigma N is algebraic by A1,YELLOW_9:52; end; assume that A3: N is with_open_semilattices and A4: InclPoset sigma N is algebraic; reconsider T = InclPoset sigma N as algebraic LATTICE by A4; T is continuous; then N is continuous by A3,Th35; then S is continuous by A1,YELLOW12:15; then for x being Element of S ex K being Basis of x st for Y being Subset of S st Y in K holds Y is open filtered by WAYBEL14:35; then A5: for V being Element of InclPoset sigma S ex VV being Subset of InclPoset sigma S st V = sup VV & for W being Element of InclPoset sigma S st W in VV holds W is co-prime by WAYBEL14:39; InclPoset sigma S is algebraic by A1,A4,YELLOW_9:52; then ex K being Basis of S st K = {uparrow x where x is Element of S: x in the carrier of CompactSublatt S} by A5,WAYBEL14:44; then S is algebraic by WAYBEL14:45; hence thesis by A1,WAYBEL_8:17; end; definition let N be meet-continuous algebraic Lawson (complete TopLattice); cluster InclPoset sigma N -> algebraic; coherence by Th40; end;