22:
133:
Actors are the primitives that form the basis of the Actor model of concurrent digital computation. In response to a message that it receives, an Actor can make local decisions, create more Actors, send more messages, and designate how to respond to the next message received. Actor model theory
864:
However, we know from physics that infinite energy cannot be expended along a finite trajectory. Therefore, since the Actor model is based on physics, the Law of Finite Chains
Between Events in the Combined Ordering was taken as an axiom of the Actor model.
146:
From the definition of an Actor, it can be seen that numerous events take place: local decisions, creating Actors, sending messages, receiving messages, and designating how to respond to the next message received.
499:
Proof. It is sufficient to show that there is an Actor computation that satisfies the previously stated laws but violates the Law of Finite Chains
Between Events in the Combined Ordering.
830:
173:) is a fundamental ordering that models one event activating another (there must be energy flow in the message passing from an event to an event which it activates).
954:
950:
135:
1217:
294:
486:
However, surprisingly proved that the Law of Finite Chains
Between Events in the Combined Ordering is independent of the previous laws,
39:
1227:
105:
406:
The combined ordering is relativistically invariant because it is the transitive closure of relativistically invariant orderings.
1033:
1022:
1013:
86:
1222:
971:
58:
43:
65:
119:
72:
976:
32:
966:
495:
The Law of Finite Chains
Between Events in the Combined Ordering does not follow from the previously stated laws.
1029:
Proceedings of the
Symposium on Artificial Intelligence Programming Languages. SIGPLAN Notices 12, August 1977.
934:
54:
774:
Furthermore all of the laws stated before the Law of Strict
Causality for the Combined Ordering are satisfied.
938:
873:
The Law of Finite Chains
Between Events in the Combined Ordering is closely related to the following law:
916:
The Law of
Discreteness is equivalent to the Law of Finite Chains Between Events in the Combined Ordering
286:
150:
However, this article focuses on just those events that are the arrival of a message sent to an Actor.
1019:
Proceeding of IFIP Working
Conference on Formal Description of Programming Concepts. August 1–5, 1977.
1188:
Proceedings of the 2004 ACM Symposium on
Applied Computing (SAC), Nicosia, Cyprus, March 14–17, 2004.
1201:
182:
1081:
Proceedings of First International Conference on Distributed Systems Huntsville, AL. October 1979.
1044:
Specification and Verification Techniques for Parallel Programs Based on Message Passing Semantics
134:
incorporates theories of the events and structures of Actor computations, their proof theory, and
399:
226:
179:
937:. The combined ordering is used by in the construction of a denotational model of Actors (see
79:
815:
1153:
1181:
International Conference on Algebraic Methodology and Software Technology (AMAST), 2004.
995:
Conference Record of ACM Symposium on Principles of Programming Languages, January 1974.
1211:
293:. The arrival ordering means that the Actor model inherently has indeterminacy (see
777:
However, there may be an infinite number of events in the combined ordering between
1158:
Analysis of inheritance anomaly in object-oriented concurrent programming languages
923:
953:. Subsequently Hewitt augmented the diagrams with arrival times to construct a
477:, linearly ordered sets) of events between two events in the combined ordering →.
482:
Independence of the Law of Finite Chains Between Events in the Combined Ordering
127:
21:
290:
1119:
927:
466:
In , it was conjectured that the above laws might entail the following law:
1160:
in Research directions in concurrent object-oriented programming. 1993.
285:
in processing messages (often making use of a digital circuit called an
277:) models the (total) ordering of events in which a message arrives at
1131:
402:
of the activation ordering and the arrival orderings of all Actors.
1192:
1179:
Techniques for Executing and Reasoning About Specification Diagrams
949:
Clinger used the Actor event model described above to construct a
1095:
IEEE Transactions on Systems, Man, and Cybernetics. January 1981.
177:
Because of the transmission of energy, the activation ordering is
1132:
Actors: A Model of Concurrent Computation in Distributed Systems
910:
In fact the previous two laws have been shown to be equivalent:
1051:
Very Large Address Space Modularly Extensible Computer Systems
301:
Because all of the events of the arrival ordering of an actor
15:
463:
The combined ordering is obviously transitive by definition.
471:
Law of Finite Chains Between Events in the Combined Ordering
1170:
Luca de Alfaro, Zohar Manna, Henry Sipma and Tomás Uribe.
1058:
Viewing Control Structures as Patterns of Passing Messages
153:
This article reports on the results published in Hewitt .
449:
in the relativistic frames of reference of all observers.
360:
in the relativistic frames of reference of all observers.
1145:
Gul Agha, Ian Mason, Scott Smith, and Carolyn Talcott.
1202:
What is Commitment?Physical, Organizational, and Social
1140:
Sequential and Concurrent Behaviour in Petri Net Theory
1100:
Reasoning about Change in Knowledgeable Office Systems
1124:
Concurrent Behaviour: Sequences, Processes and Axioms
818:
243:
Law of Finite Predecession in the Activation Ordering
1074:
IEEE Journal on Software Engineering. January 1979.
233:
Law of Strict Causality for the Activation Ordering
46:. Unsourced material may be challenged and removed.
1077:Carl Hewitt, Beppe Attardi, and Henry Lieberman.
1072:Specification and Proof Techniques for Serializers
824:
503:Consider a computation which begins when an actor
1116:MIT Mathematics Doctoral Dissertation. June 1981.
951:denotational model for Actors using power domains
511:message causing it to take the following actions
453:Law of Strict Causality for the Combined Ordering
1177:Thati, Prasanna, Carolyn Talcott, and Gul Agha.
1149:Journal of Functional Programming January 1993.
933:The Law of Discreteness implies the property of
1167:Journal of Computer Software Engineering. 1995.
1126:Lecture Notes in Computer Science Vol.197 1984.
1027:The Incremental Garbage Collection of Processes
364:Law of Finite Predecession in Arrival Orderings
1060:Journal of Artificial Intelligence. June 1977.
1046:MIT EECS Doctoral Dissertation. December 1977.
1067:MIT EECS Doctoral Dissertation. January 1978.
1002:MIT EECS Doctoral Dissertation. August 1975.
1000:Semantics of Communicating Parallel Processes
289:). The arrival events of an Actor are on its
8:
1142:Theoretical Computer Science Vol.55/1. 1987.
1109:MIT EECS Doctoral Dissertation. August 1981.
1102:MIT EECS Doctoral Dissertation. August 1981.
1165:A Logic for concurrent programming: Safety
1053:MIT EECS Doctoral Dissertation. June 1977.
160:: There are at most countably many events.
1184:Giuseppe Milicia and Vladimiro Sassone.
1037:Laws for Communicating Parallel Processes
817:
106:Learn how and when to remove this message
1186:The Inheritance Anomaly: Ten Years After
1172:Visual Verification of Reactive Systems
1065:Actor Systems for Real-Time Computation
295:Indeterminacy in concurrent computation
1088:MIT Doctoral Dissertation. June, 1980.
955:technically simpler denotational model
681:message (which we will call the event
309:, the arrival ordering of an actor is
1086:Automatic Verification of Serializers
281:. Arrival ordering is determined by
7:
918:(without using the axiom of choice.)
126:concerns theoretical issues for the
44:adding citations to reliable sources
993:Actor Induction and Meta-evaluation
1194:Zeno machines and hypercomputation
1147:A Foundation for Actor Computation
922:The law of discreteness rules out
819:
394:The combined ordering (denoted by
14:
1093:The Scientific Community Metaphor
1017:Actors and Continuous Functionals
473:: There are no infinite chains (
269:The arrival ordering of an Actor
1091:Bill Kornfeld and Carl Hewitt.
1070:Carl Hewitt and Russ Atkinson.
20:
972:Actor model and process calculi
559:is as follows on receipt of an
31:needs additional citations for
1218:Actor model (computer science)
1114:Foundations of Actor Semantics
1107:Parallelism in Problem Solving
957:that is easier to understand.
655:(which we will call the event
570:(which we will call the event
1:
1135:Doctoral Dissertation. 1986.
1079:Delegation in Message Passing
926:and is related to results on
621:Obviously the computation of
305:happen on the world line of
120:theoretical computer science
1138:Eike Best and R.Devillers.
1007:A discipline of programming
644:When it receives a message
634:The behavior of each Actor
555:Thereafter the behavior of
1244:
977:Actor model implementation
629:messages never terminates.
589:which is sent the message
521:which is sent the message
311:relativistically invariant
186:; that is, for all events
142:Events and their orderings
967:Actor model early history
753:every time and therefore
718:every time and therefore
169:The activation ordering (
1228:Mathematics of computing
935:unbounded nondeterminism
695:Now it is possible that
825:{\displaystyle \infty }
398:) is defined to be the
1223:Denotational semantics
945:Denotational semantics
939:denotational semantics
826:
218:precedes the time of
1152:Satoshi Matsuoka and
1039:IFIP-77, August 1977.
827:
563:message with address
455:: For no event does
442:precedes the time of
353:precedes the time of
235:: For no event does
1009:Prentice Hall. 1976.
816:
610:with the address of
542:with the address of
525:with the address of
225:in the relativistic
55:"Actor model theory"
40:improve this article
1204:COINS@AAMAS. 2006.
878:Law of Discreteness
869:Law of Discreteness
690:), it does nothing.
677:When it receives a
582:Create a new actor
514:Create a new actor
435:. then the time of
346:, then the time of
227:frames of reference
211:, then the time of
165:Activation ordering
158:Law of Countability
136:denotational models
1191:Petrus Potgieter.
880:: For all events
822:
400:transitive closure
366:: For all events
245:: For all events
124:Actor model theory
1005:Edsger Dijkstra.
410:, for all events
390:Combined ordering
317:, for all actors
265:Arrival orderings
229:of all observers.
116:
115:
108:
90:
1235:
1163:Jayadev Misra.
1154:Akinori Yonezawa
1105:Bill Kornfeld.
1084:Russ Atkinson.
1032:Carl Hewitt and
1025:and Carl Hewitt
1012:Carl Hewitt and
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893:
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180:relativistically
172:
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24:
16:
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1234:
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1208:
1207:
1112:Will Clinger.
1098:Gerry Barber.
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903:
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708:
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641:is as follows:
639:
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625:sending itself
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998:Irene Greif.
996:
984:
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974:
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735:
729:
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699:
693:
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671:
664:), it sends a
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2:
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1097:
1094:
1090:
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1080:
1076:
1073:
1069:
1066:
1063:Henry Baker.
1062:
1059:
1056:Carl Hewitt.
1055:
1052:
1049:Peter Bishop
1048:
1045:
1042:Aki Yonezawa
1041:
1038:
1035:
1031:
1028:
1024:
1021:
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988:Carl Hewitt,
987:
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952:
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924:Zeno machines
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913:
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911:
879:
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859:
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662:
654:
648:with address
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616:
605:
601:
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593:with address
588:
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99:
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81:
78:
74:
71:
67:
64:
60:
57: –
56:
52:
51:Find sources:
45:
41:
35:
34:
29:This article
27:
23:
18:
17:
1200:Carl Hewitt
1193:
1185:
1178:
1171:
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746:
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727:
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669:
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635:
622:
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606:the message
603:
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583:
572:
564:
556:
543:
538:the message
535:
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93:
83:
76:
69:
62:
50:
38:Please help
33:verification
30:
1174:TACAS 1997.
1129:Gul Agha.
1034:Henry Baker
1023:Henry Baker
1014:Henry Baker
914:Theorem .
795:as follows:
668:message to
373:and Actors
321:and events
283:arbitration
128:Actor model
96:August 2011
1212:Categories
983:References
928:Petri nets
906:is finite.
894:, the set
855:SayHelloTo
841:SayHelloTo
789:SayHelloTo
728:SayHelloTo
712:SayHelloTo
658:SayHelloTo
646:SayHelloTo
591:SayHelloTo
523:SayHelloTo
507:is sent a
493:Theorem.
385:is finite.
379:{e|e -x→ e
291:world line
260:is finite.
254:{e|e -≈→ e
66:newspapers
1120:Eike Best
820:∞
183:invariant
961:See also
377:the set
252:the set
705:Greeter
670:Greeter
650:Greeter
636:Greeter
623:Initial
612:Greeter
604:Initial
595:Greeter
584:Greeter
565:Greeter
557:Initial
544:Greeter
536:Initial
527:Greeter
516:Greeter
505:Initial
287:arbiter
237:e -≈→ e
80:scholar
990:et al.
82:
75:
68:
61:
53:
848:Hello
846:→...→
834:Hello
807:Again
805:→...→
800:Again
780:Again
763:Again
756:Again
747:Again
740:Again
737:Also
721:Hello
698:Hello
684:Hello
679:Hello
666:Hello
627:Again
608:Again
602:Send
573:Again
561:Again
540:Again
534:Send
509:Start
424:, if
341:-x→ e
335:, if
206:-≈→ e
200:, if
87:JSTOR
73:books
1197:2005
900:→e→e
896:{e|e
887:and
832:...→
812:→...
786:and
745:-≈→
488:i.e.
475:i.e.
408:I.e.
315:I.e.
275:-x→
59:news
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765:i+1
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42:by
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