[fspeech]

Wow I am just floored by the thoroughness of your answers. Just want to let you know that someone enjoyed your effort though tbh I may never fully digest all you said here (and I do plan to read what you wrote a couple more times).

"Most working physicists don't really care what are in the foundations, to the great annoyance of many philosophers."

I was in physics grad school over twenty years ago. Your statement is accurate as far as I can tell. I did and do care about certain foundation issues. In particular I care whether free will is even fundamentally possible. However I never find any philosophical discussion capable of advancing my understanding "meaningfully", as in "to a physicist".

[raattgift]

Thanks.

> I did and do care about certain foundation issues.

I meant more that while many foundational questions are interesting, the absence of conclusive answers don't stop most working physicists from making progress in their areas of professional interest.

For example:

> I care whether free will is even fundamentally possible

We act like it is. Similarly, we predict our past with greater fidelity than we predict our future, and we have a sense of "now".

Are these behaviours tied to something physically fundamental, or are they emergent? Nobody knows.

It'd be nice if we could have a long chat with a grey parrot or an octopus and find out whether it has a different view of past and future. Maybe we'd learn that it remembers in both directions equally well, and so doesn't really distinguish between them. Perhaps our future-directed memory was just an anatomical sacrifice like many others during the food-energy bottlenecks that dot humanity's evolution, and the cost of survival of our ancestors is us having a peculiar attitude towards time (and sports, like Wayne Gretzky's line about skating to where the puck will be) compared to less closely related organisms on our planet. ("Squawk, the future-memory part of your brain is missing, like the part of your brain that would deal with your vomeronasal organ. You will pass me a cracker now, while convincing yourself that you decided to. Squawk."

Since we are unable to have such interspecies conversations right now, we can only discuss this among ourselves, and are all stuck with essentially the same anatomy and no fossil early human brains to compare to ourselves.

I can understand the temptation to think that the very common idea of a fixed past and an undetermined future is a feature of the universe as a whole rather than something like impacted wisdom teeth or an inflamed appendix.

On the other hand, I think outright working (as in a likely self-funded job) on answering free-will-or-not is somewhere between pretty unproductive philosophizing and early symptoms of the sort of obsessions which overtook Linus Pauling, Brian Josephson, William Shockley, or Jack Parsons (among sadly too many others). Yes, that's a dickishly prejudicial thing to admit to, whether or not the attitude was determined by the information on a slice of the universe coupled to physical laws that let one recover the information everywhere else in the universe. As almost all of the content of any cross-universe slice is practically inaccessible to us, blaming eternalism or determinism for my "hot take" seems like a cheat.

In practice, though, none of this is likely to even occur to me consciously as I grind through different field equations, or try to match results from a static (time-independent) spacetime to a mostly-similar dynamical (varying over time) one, for example.