Abstract

In [2] a space PCSP of probabilistic processes is constructed uniformly from the standard CSP failures-divergences model. Laws of CSP are shown to be valid in PCSP also, provided they have no duplication on either side of = or v separately: thus for example A u B = B u A carries over to PCSP; but AuA = A does not, because of the duplication on its left-hand side. Here we propose two devices for retaining more of CSP's laws within PCSP: the first introduces a limited form of state; the second allows multiple occurrences of a term to be abstracted to a single syntactic location. Either [2] or its published revision are prerequisites for understanding this report fully, although skimming Sec. 4 and App. A may give an idea of what has been achieved. 1 Introduction The law A u A = A fails in PCSP only when A is properly nondeterministic; and when that is so, the reason for its failure is the possibly independent resolution of probabilistic choice in the two copies. For example, (B 1 2 \...

Citations