Putting the 'Pre' in 'Unpredictability' by Emily Christine Adlam

Thank you very much for reading the essay, and for your comments!

I actually agree entirely with what you say - I think the 'how-enforced' questions is just as difficult for the billiard ball case as for the global constraint case. However, the point I was trying to make is that for many people, the 'how-enforced' problem looks worse in the global case, because we can't resort to the intuitive picture of small particles colliding that we have all internalised. Thus global theories are often viewed as less plausible than local theories, even though the problems of principle are really the same in each case.

I also have a lot of sympathy with the idea that the 'how-enforced' question isn't actually well-formed and that physicists should learn not to ask it. My concern, however, is that even if physicists don't raise such questions explicitly, nonetheless we may still have ideas of this type in the back of our minds when we evaluate the relative plausibility of various theories, and this can potentially lead to unjustified prejudice against certain types of theories (such as global ones).

Thank you for reading, and for your comments!

I'm glad you raise the subject of thermodynamics, because I think it's a really interesting example of a theory which mixes physical laws with perspectival elements. The Boltzmann entropy, for example, is in some sense a summary of how much information we have (or rather, lack) about the microstate of a system, and so the second law of thermodynamics can in some sense be thought of as a reflection of the fact that if we prepare a system in a known state and then let it evolve, we will inevitably lose information about it. (I am grossly oversimplifying of course!). So the fact that it takes the form it does is certainly a consequence of our interest in taking initial states and projecting them forward in time.

Thank you very much for reading and for your comments! I'm excited to hear that you're working on ideas similar to this and I'm looking forward to reading your essay.

Thank you very much for reading! I definitely agree with your comments on the importance of conceptual understanding - as you say, we never fully came to grips with the conceptual elements of quantum theory, and this has affected all the physics that has been done since. So studying the interpretation of quantum mechanics isn't just a matter of intellectual curiosity, it's a promising route toward making new progress in physics.

I look forward to reading about your new approach to the interpretation problem!

Thank you for reading, and for your comments!

I'm very interested in what you have to say about locality. I should clarify that I don't necessarily believe physics definitely can't be local - what I intended to convey in the essay was that if we accept Bell's theorem then we can't have locality (regardless of whether we have determinism) - but of course there are various ways of getting around Bell's theorem, such as the Everett interpretation or superdeterminism. For various reasons I'm a bit sceptical about both of those, but I'm always interested in new takes on this issue and I look forward to reading your essay!

Thank you for your comments!

At present I don't know of any examples of retrocausal theories actually yielding new predictions. However, there seems to be quite a lot of evidence that quantum mechanics may actually be retrocausal in character (e.g. see the recent paper by Leifer and Pusey). And if the laws of nature are in fact retrocausal in character, then it seems to me likely that the best way to make progress is to allow ourselves to write down laws which are retrocausal and try to understand what their consequences would be for the world as we observe it.

Thank you for reading! I'm interested to see how limitations on knowability affect predictability, and I'm intrigued by the suggestion that there could be some way to have definite knowledge of ontology, so I look forward to reading your essay!