Dear Luca,
I was happy to see another essay of yours, and I'm sorry you didn't have time to develop it more fully, since I think the ideas you're working with are important. The key issue is how to include possibility as a basic category - that is, how to describe what happens such that each new fact that appears in the world contributes to the physical "process schemes" that make further events possible.
Armin Nikkhah Shirazi has an essay in this contest that also tries to develop a logic where possibility plays a basic role. I'm also reminded of Ruth Kastner's "possibilist" version of the Transactional Interpretation of quantum mechanics. In both these cases, though, possibility seems to be conceived as "a mode of existence" that has to be taken into account alongside actuality. That is, it's relevant to quantum physics, but otherwise doesn't change very much how we think about time. Evidently von Weizsäcker was trying to work out a deeper notion, something like Heidegger's concept of temporality, where factuality and possibility are both essential aspects of present-time happening.
Incidentally, thanks for the note on Michael Drieschner's books. His volume on Philosophy actually just arrived in the mail as I'm writing this - so I'll finally get a broader view of von Weizsäcker's thinking. It's interesting that he seems to take over Plato's eidos as a way to talk about the structure of our possible experience.
I agree with you that measurement is a primary issue, and that it needs to be understood as a physical "transfer of information from one system to another", i.e. as communication. I'm sorry I'm not better equipped to follow your discussion of the "measurement field", though it's clearly related to what you explained at more length in your essay last year.
Apparently you're thinking of entanglement with this field as the default condition of things when they're not being measured, but which defines the parameters within which a particular measurement can take place? If that's right, then there may be a connection with my discussion of observable parameters in my essay on the mathematical language of physics. My emphasis is on the need for different kinds of parameters, to make a physical environment in which any of them are meaningfully definable. Your (tentative) model abstracts from the specific parameters, to give general conditions for the possibility that a qbit of information about one system can be determined by another.
Let me know if this is off track. Also, can I ask you to clarify the role of the time-logic in this model?
Thanks - Conrad