Path: utzoo!utgpu!watmath!thunder!water!wlrush
From: wlrush@water.waterloo.edu (Wenchantress Wench Wendall)
Newsgroups: ont.events,uw.talks,uw.cs.grad
Subject: PROGRAMMING LANGUAGES SEMINAR
Keywords: Professor Faron Moller, University of Strathclyde,
Message-ID: <2467@water.waterloo.edu>
Date: 22 Jun 89 13:01:19 GMT
Distribution: ont
Organization: U of Waterloo, Ontario
Lines: 44

Glasgow, Scotland, will speak on 
``Some Thoughts on the Algebraic Theory of Concurrent Process.''

DEPARTMENT OF COMPUTER SCIENCE
UNIVERSITY OF WATERLOO
SEMINAR ACTIVITIES

PROGRAMMING LANGUAGES SEMINAR

                    -Thursday, June 29, 1989

Professor  Faron  Moller,  University  of  Strathclyde,
Glasgow,  Scotland,  will speak on "Some Thoughts on the
Algebraic   Theory   of   Concurrent   Process."  

 
TIME:              3:30 p.m.

ROOM:              DC 1302

ABSTRACT

In  this  talk,  we  consider  several  aspects  of the
mathematical   foundations   of   processes   algebras.
Starting  from  the basic notion of finite automata and
regular  expressions,  we introduce parallelism (in the
form  of  the  so-called shuffle operator), and discuss
some  results  and  conjectures  on  the  existence and
uniqueness of the decompositions of machines.

Next,  we  argue  for  a tightening of the semantics of
finite  automata,  and  move from a discussion of trace
equivalence   to   the   more   restrictive  notion  of
bisimulation  equivalence. We ask the same questions on
decomposability,  and find ourselves able to prove more
here than in the language equivalence case.

We    then    consider    properties    of   equational
axiomatisations  for  our  equivalence and show that no
finite characterisation can exist. We extend our result
to cover all reasonable notions of equivalence, and use
this  as  an  explanation  to  the  difficulty faced in
trying  to find algebraic characterisations of sensible
noninterleaving semantic equivalences.