Re: pi-calculus

[A E Lawrence <adrian.lawrence@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>]

"B.M. Cook" wrote:
> 
> Rick,
> 
> > Could someone briefly summarise what pi-calculus is please?
> 
> Not properly - but the summary I have (I hope it's right) is that it is CSP
> plus channels that can be passed around on channels, hence the end-points of
> communications can be moved (in a controlled way). It is of particular
> interest to the mobile computing gropups, e.g. David May at Bristol who has
> a new language based on it. It is also a great way to provide low-overhead
> servers, just pass the channel to the client, no need to collect and forward
> data.


Eh, not really. The book to read is "Communicating and Mobile systems:
the pi calculus" By Robin Milner  ISBN 0521658691.  \pounds 15, so
affordable. 161 pages.  It supercedes some of the earlier descriptions. 
I am not offering to summarize because I am still a novice.  One view is
that it is a sort of lamba-calculus for concurrency. It seems to be very
discrete, and I don't think that it could be extended to describe real
continuous phenomena in the way that CSP can.  Of course, Barry is right
in that pi-calculus models changing connectivity in interacting
concurrent systems.

Adrian
-- 
Dr A E Lawrence (from home)