by [Theo Verelst] (of course feel free to comment / correct, pref. with id)

The [Process Algebra] page gives an idea of that concept, but lacking in it was some indication of the algebraic manipulation that is of interest, and that, of course, is a major reason for the algebraic angle.

Distributiveness, associativeness, substitution of the parallel and serial composition and the restriction operator.

''[escargo] 27 Apr 2003'' - I see interesting strings of characters here, but I can't tell
what the notation is supposed to denote.  I can't tell if '''^=''' is supposed to be ''not equals'',
''equals'' (under some special assumptions), ''equivalence'', or ''implies''.  '''Wait!'''
Now I see that it means ''is defined as'' (which got added since the last time I looked).
Maybe all these notations could be collected and defined in the beginning.
[TV] Agreed, this page stated as sort of a scratch to recollect this stuff. I'm in the library now, I'll see if I can find some nice existing frame with some history, before thinking it all up myself again.

Let's see (sort of like typing while my memory and imagination are working, I should do my library work first, in fact), starting with parallel composition of agents capable of communication with a certain message set and a certain set of state progression orders:

 (A | B) | C  ^= A | (B | C) ^= A | B | C

  A | B  ^=  B ^| A 
[TV], nope, I think I must have (or should have) typed:
  A | B  ^=  B | A  
Parallel composition simply doesn't depend on the algebraic ordering of the defining composition. A | B means the same as B | A: processes A and B are put together in a composition and may communicate with each other. The ^= I made stand for ''is defined as''


Serial composition:

 A ; B  !=  B ; A

 ( A ; B ) ; C ==> ( A ; C ) &&  ( B ; C )

Combined:

 ( A | B ) ; C ==>


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Oh boy, still thinking, don't take this for granted, it's been years....