Dear Vaughan, An excellent remark, once again from your side. The general audience of this remark may, however, not identify the subtlety of these states with respect to modelling of parallel programs and what apparently now happens on clouds and grids with services and brokers, and not even to mention customers using these services. So perhaps I may suggest to recall e.g. the dining philosophers paradigm, which was widely used during the early days of CSP (Communicating Sequential Processes) decades ago. The philosophers go through only three states, namely, thinking, getting hungry (and thereby stop thinking), and eating. After eating then go back to thinking, and so on. They use chopsticks, one by one (in a very non-Asian fashion), and communicate about using these resources with fellow philosophers around the table. Simple objectives are e.g. to avoid starvation. The relationship between states you mention is much more elaborate, they overlap, and it is not entirely clear when one state is over, and another one begins. I would even say that some of these states, in the sense of being members of a "set of states", call for more structure in underlying categories. Perhaps you already thought about transforming this into a new paradigm. I seriously think it would be a challence to the CSP programmers (some of them fascinated e.g. by Goguen's institutions!) to encode some behaviour involving those states in conventional CSP, and making the observation that we may need additional language constructions, and more underlying structures. The parallel paradigm is still all too non-categorical. Cheers, Patrik On Sat, 12 Nov 2011, Vaughan Pratt wrote:
On 11/9/2011 4:45 PM, Jocelyn Ireson-Paine wrote:
What's the definition of "weakening"? I've not seen this word used formally.
I had the same question about "boring", which came earlier. I believe "sleeping" comes later, then "dreaming," "awakening," and so on. Eventually the lecture ends and we either resume elsewhere with "boring" or move on to "eating."
Vaughan
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