Graph Lambda Theories † a N T O N I O B U C C I a R E L L I and a N T O N I N O S a L I B R A
نویسندگان
چکیده
A longstanding open problem in lambda calculus is whether there exist continuous models of the untyped lambda calculus whose theory is exactly the λβ or the least sensible λ-theory H (generated by equating all the unsolvable terms). A related question is whether, given a class of lambda models, there are a minimal λ-theory and a minimal sensible λ-theory represented by it. In this paper, we give a positive answer to this question for the class of graph modelsà la Plotkin-Scott-Engeler. In particular, we build two graph models whose theories are respectively the set of equations satisfied in any graph model and in any sensible graph model. We conjecture that the least sensible graph theory, where " graph theory " means " λ-theory of a graph model " , is equal to H, while in one of the main results of the paper we show the non-existence of a graph model whose equational theory is exactly the λβ theory. Another related question is whether, given a class of lambda models, there is a maximal sensible λ-theory represented by it. In the main result of the paper we characterize the greatest sensible graph theory as the λ-theory B generated by equating λ-terms with the same B ¨ ohm tree. This result is a consequence of the main technical theorem of the paper: all the equations between solvable λ-terms, which have different Böhm trees, fail in every sensible graph model. A further result of the paper is the existence of a continuum of different sensible graph theories strictly included in B.
منابع مشابه
Amitraz Poisoning; A case study
A m i t r a z, a n i ns e c t i c i d e /a ca ri c i de of the f o r m a m i d i n e p e st i c i d e s group, is a ? 2 a d r e n e r g i c ag on i st a nd of t he a m i d i ne c h e m i ca l f a m il y generally us e d to c o n t r ol animal e c top a r a s i t e s. Poisoning due to am i t r a z i s r a r e and character...
متن کاملتاثیر مرکزی هیستامین بر درد فرمالینی در خرگوش: نقش سیستم اپیوئیدی
.yiU s1 r qdJ 9 6!r.1 l,-r,iU 61 r,r1.11 ;oal il go,-7^19 ai f * *,-) S '*{'?'J*'fL' t:::tc: l/'2f /2 g.6;gb.t e*)* +r-,JifF.'L!.p"i9 r:.",ii:oul9+ 'Fft s ;J"r.pbjr;^*f- $ J9b +9 ll o;lr"iJ$!l odjUll Jt'56rlr2lr.! :rti9, ,(Jt;5) O*Jt"Jt i,;;ia.rJ1.pll oQr.i; nlCel ."r95f a+1,,r-..;ta 4..59L*yrtirlrcrbtUg i*r..p.259Fl'tfA,lflA.;lLirl,r6ek- 5r crrt!"rlr (efs.s..o' ) o*:..i1 Ji (.fsfefa),-;...
متن کاملمطالعه فراوانی تیپ های مسمومیتزای انسانی کلستریدیوم بوتولینوم (A, B, E) در بعضی از ماهیان دریای شمال( سفید و کفال) و ماهیان دریای جنوب ( شوریده و حلوا) ایران
. (vr"+ ) lt s o{,9^is (Jt"j)Jtise r^il3tpb :oUle+ .,jti I dlir..9* db* s9"9 jJ j | .+1,. er- )LAe.1 I +.i9r; lf ' :.p9, .Lgr;lortjr;rlt, (a;r"; f f. VS),rilt9 !)9) air.ir)J) e 4y e+ yql*S JL;,r ol.icJ5 6lndit i . r;ii,S,lr! aiJ";icr9. a-i.1 oif6-f- r.r-f ortir-l t 9 ac!,51!!;,*Sf ,:t*- o:.J.i1 trS".* f q rg rf ,r- },l'j*.Ft . r,:f;.s.; ;oJi :ni 5rlJUrl Jylgig"dLbO*Ji,riijl cdlGglii reJJg...
متن کاملمطالعه میکروبیولوژیک و کلینیکال پاتولوژیک تورم مفصل عفونی در گاو
.r!r5! &tL,"1ei;r.r.laL 61b 4ittq J5r.lsol.,J.'i s!)t :!eaA .e6 .uthiauutY:.7tb 'pJt-96o"L f 9 s* ;;taafu 9S o"ttV :oUles 1r pJt"96a.r! fA9 c{;r'i4Jy,i"rrSr"'t, ttV 'JdL AJ" ,51o*9; :rta9t ,JFli,.,.:.15 lq,Jlt slsi. eJ.,:,:5 . Sd'aref6lal.il.;bl.5bo6;ti'i5 9 J*.5bc,,U. it9 6ta$ ota;.i.. $pt29l ll1^x9 tbtey?95.io,li .gbJ9al5 sl*r; . d elftl !h* 9 y'Lr "5b," I ),,la.l.a p]r" gr.rf .r#S"...
متن کاملشناسایی کلستریدیوم سپتیکوم به روش واکنش زنجیره ای پلیمراز (PCR)
li . a3"9rl aiL,;.61'l,.lo95g9s,r";lo.r;'l,q,Jtaer{J*-;*J5O+.t1r (PCR) al:9, .,rat5':.1"ri+.ltL" : g rb .a991la.iL;.5$.ir 95 2g;,r, A 9; *a llo'r,il.spyl.;-*l5ar-9ulA :ba!9al u9fe,rrl.lhrl ol..id4jlpbd I . 6.r^ir95o;U g9s'tn 31 6 tl ty. * y; : t;' 9 t l, PCR pt+l .bte-;IDNA 6l.g*l ,LJ:.1;"-J5d;t h+i5lt.#t^i .A.J'-6Jij j4'f.i 1l o'& u>lp uet a3l.5b.rol;;l osl'i;rl {f fupt{tl*J5 t;*Sl 9a:-...
متن کاملبررسی مورفولوژی غدد جنسی در ماهی قزل آلای رنگین کمان Oncorhynchus mykiss پس از تجویز هورمون 17 آلفا- متیل تستوسترون به دو روش خوراکی و یا غوطه وری
Jai" -UJllY A9")94 l9?qi r:rd crr*& t, 9 i 4r cr..J+ rnij tfi;a a: a5 'r;lga;sfrltig 9t*,tN .uPaaf au"Jtha:.7tb . at"5;"J31.5VTJ,r,,lb : oU19+ cq,j s r ( J : J{ j e'.i,qrl.i A r s 69;lw9i*i rlgr - U,TIV Orp)9ajJ r?6 : rigr -tirJTlV t9.)rApL>1s os; a-{6!1,r6[l91Y9 or; $q ,garlt ,g29&9i (1,;9, A alrG!ocl,!9)oroa).i1r.r)f6.r5..Y4.)lai.. q OIP F,b r.rr;* pl.rrs orr; a..5!5Lls dta9.1Y9 or; pi...
متن کامل