Dear Giacomo
I found your essay very interesting and well structured. However, I have a view in opposition to yours. Just as Olaf and Maria Carrillo argue, I support the view that information has no meaning without objects (it). I'd like to express some critics on your work and I'd be glad if could make some comments.
As far as I could see you support the view that information (bit) is more fundamental than the substance (bit). To state your position you invoke pragmatism and operationalism whose bases, according to you, rest on what we "observe" and not on what we believe is out there. My first point is that I don't have clear what you mean by "what we believe is out there" if what is out there is supposed to be what we "observe" with our senses and instruments. Could you please clarify.
You also mention that what matters is making correct predictions and that we only need to describe logically and efficiently what we "see". I concur with you that theories should account for physical phenomena and I assume that by the words "observe" and "see" you mean "data collected by measuring instruments". It appears that many colleagues have forgotten that since the advent of QM and GR intuition and common sense (or ontologies as you say) were relegated to a second plane in physics and replaced by mathematical formulations. In my opinion operationalism is synonymous of the famous "shut up and calculate" approach. Operationalism has been practiced for many decades since the first quarter of the XX century, and without doubt is the cause that has brought us to the present state in physics. The fact that our understanding of the world has been restricted to ever increasing abstract theories is, in my view and the view of many other renown physicists, the real cause of not making progress in the last 30 or more years in theoretical physics. This is the reason why nowadays we found many different roads to "reality" or ontologies such as string theory, causal sets, LQG, including the one we are discussing in this contest. Therefore, the ontology of object has not precluded the progress of physics. Moreover if we consider that ontologies are tools to depict mechanisms of "what we believe is out there" (observations) in our mind, then we can assert that information and math can be considered in a certain sense as some kind of "ontologies", after all math is also a mental tool composed of pure logical structures and abstract objects that we humans have develop to help ourselves in understanding the world out there. We cannot deny that there are some colleagues who argue that the universe has mathematical structures, some even go beyond this asseveration and claim that the universe is pure math. If we acknowledge this, then the problem likely reduces to a mere problem of interpretation, language or thus of semantics. Whereas in the current view we assume that the main ingredients that make up the universe are matter, energy, space, time, and fields; the "it from bit" ideology suggests that the main ingredient is information in the form of states or bits. But what is a bit or information? And what physical meaning do they have without hardware? If they are states, they should be states of something tangible... the fact that they are states doesn't imply that they stop being objects.
Thus, I took your question: Why we should bother changing our way of looking at reality? And your answer is: Because the old matter-realistic way of thinking in terms of particles moving around and interacting on the stage of space-time is literally blocking the progress of theoretical physics.
The ontology that matter is a essential substance of the universe is neither deficient nor precluding the progress of physics but what is deficient is the conception of particle. The solution that you offer is to throw out the baby with the bath water. I wouldn't replace the "it" for the "bit", instead I would replace first the ontologies of particle and wave for only one ontology that encompasses both and to do so I have to reconceptualize the ontologies of space and field. This is what I discuss in my current and previous essays.
You say: The lesson spelled loud and clear by the Bell theorem is that we should trust observations, even against our intuition.
Again, "observations" means "data" and data can be interpreted by more sophisticated ontologies that go along with intuition and common sense and that keep the "it" as the fundamental ingredient. Some colleagues are working on showing that entanglement (and thus non-locality) can have an intuitive explanation (which is actually very simple if we change our notion of particle).
Later you talked about a field, but what is a field made of? You say: It is a collection of infinitely many quantum systems. But the "quantum system" is an abstract notion: it is an immaterial support...
That the field is a mathematical abstraction is due to Einstein since then most physicists believe so, but this doesn't forbid us to recover the notion of field as conceived by Maxwell. So a field can be considered a state of the quantum vacuum and we can postulate, without fear of falling into inconsistencies, that the vacuum is a material continuum. Therefore, we are left again with matter and hardware as the fundamental essence of the universe.
Finally, I'd like to invite you to read my essay, I'd be grateful if could leave me your comments.
Best Regards
Israel