Relations in concurrency

The theme of this paper is profunctors, and their centrality and ubiquity in understanding concurrent computation. Profunctors (a.k.a. distributors, or bimodules) are a generalisation of relations to categories. Here they are first presented and motivated via spans of event structures, and the semantics of nondeterministic dataflow. Profunctors are shown to play a key role in relating models for concurrency and to support an interpretation as higher-order processes (where input and output may be processes). Two recent directions of research are described. One is concerned with a language and computational interpretation for profunctors. This addresses the duality between input and output in profunctors. The other is to investigate general spans of event structures (the spans can be viewed as special profunctors) to give causal semantics to higher-order processes. For this it is useful to generalise event structures to allow events, which "persist".

[1]  I. Moerdijk,et al.  Sheaves in geometry and logic: a first introduction to topos theory , 1992 .

[2]  Glynn Winskel,et al.  Profunctors, open maps and bisimulation , 2004, Mathematical Structures in Computer Science.

[3]  S. Maclane,et al.  Categories for the Working Mathematician , 1971 .

[4]  Glynn Winskel Name generation and linearity , 2005, 20th Annual IEEE Symposium on Logic in Computer Science (LICS' 05).

[5]  Glynn Winskel,et al.  Bisimulation from Open Maps , 1994, Inf. Comput..

[6]  Glynn Winskel,et al.  Petri Nets, Event Structures and Domains , 1979, Semantics of Concurrent Computation.

[7]  Gilles Kahn,et al.  The Semantics of a Simple Language for Parallel Programming , 1974, IFIP Congress.

[8]  Glynn Winskel,et al.  Event Structure Semantics for CCS and Related Languages , 1982, ICALP.

[9]  F. William Lawvere,et al.  Metric spaces, generalized logic, and closed categories , 1973 .

[10]  Patrick Lincoln,et al.  Linear logic , 1992, SIGA.

[11]  Marcelo P. Fiore,et al.  Mathematical Models of Computational and Combinatorial Structures , 2005, FoSSaCS.

[12]  Glynn Winskel,et al.  Petri Nets, Event Structures and Domains, Part I , 1981, Theor. Comput. Sci..

[13]  A. Joyal Foncteurs analytiques et espèces de structures , 1986 .

[14]  Glynn Winskel,et al.  Events in computation , 1980 .

[15]  Glynn Winskel,et al.  Domain theory for concurrency , 2003, Theor. Comput. Sci..

[16]  Glynn Winskel,et al.  A relational model of non-deterministic dataflow , 1998, Mathematical Structures in Computer Science.

[17]  Glynn Winskel,et al.  Weak bisimulation and open maps , 1999, Proceedings. 14th Symposium on Logic in Computer Science (Cat. No. PR00158).

[18]  Samson Abramsky,et al.  Handbook of logic in computer science. , 1992 .

[19]  Vaughan R. Pratt,et al.  Modeling concurrency with partial orders , 1986, International Journal of Parallel Programming.

[20]  Glynn Winskel,et al.  Linearity in process languages , 2002, Proceedings 17th Annual IEEE Symposium on Logic in Computer Science.

[21]  William B. Ackerman,et al.  Scenarios: A Model of Non-Determinate Computation , 1981, ICFPC.

[22]  Mogens Nielsen,et al.  Models for Concurrency , 1992 .