0 upvotes, 1 direct replies (showing 1)
Careful work has been done to establish limits on the possibility of "hidden variables" in quantum mechanics. Hidden variables would have measurable consequences which we can see don't occur in experiments. It seems that the universe is filled with brute facts (at least up close).
I'm not an expert on quantum theory but I'm assuming you're referencing Bell's inequalities? I'm not sure how that truly undermines the principle of sufficient reason, all it may rule out is locality, there could still be non-local hidden variables. But even if we rule out hidden variables all together then all this does is undermine a deterministic explanation, not a probabilistic one. So if you take PSR as an assumption then there's really no problem here.
Comment by fuseboy at 02/02/2025 at 19:00 UTC*
2 upvotes, 1 direct replies
Locality is a restriction that if something has an effect, it must do so through some field or propagation that is present at the point in spacetime where the effect occurs. Non-locality undoes classical causality, with effects occurring over so-called spacelike intervals. This opens the door to the future influencing the past and so on. It's an expensive constraint to break.
But as written, the PSR doesn't require causes to be in the past, it works with retrocausality. The laws of physics are time symmetrical, so causal relationships work both ways in time. (Your arrival at the intersection is necessitated by the crash you have, etc.)
I'm fine with probalistic explanations, but are these not contingent outcomes? A scattering electron will obey a deterministic distribution of possible outcomes, but the precise outcome is a contingent fact, not derivable from a cause (except if you sacrifice the normal understanding of causality, per Bell).