How do you know this?
No. The sort of “perfect knowledge” required for this is not just the state of the uranium lump, but of the entire universe. And even then it is not clear whether the time of the decay event is information one could extract out of the universe’s wave function without a “measurement”, what ever that means at that point.
If superdeterminism is true, then there should at least be a wave function of the entire universe. Admittedly, this agrees with my intuitive feelings on the subject: After all, why should there be a restriction as to what size a system described by Schrödinger’s equation can be? Still I must stress, that we have, for the time being, no experimental indication (or means to obtain any) that there is, in fact, a universal wave function. We have no indication that quantum theory as we know it would apply to such a thing either.
I agree, this is off-topic concerning free will, specifically. It is, however, important concerning determinism, which, for better or for worse, is often an accompanying discussion. Technically, I agree, these can be treated as separate questions.
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Just came across this article in my Slashdot feed. It seems somewhat relevant:
‘Shut up and calculate’: how Einstein lost the battle to explain quantum reality
In one kind of experiment, an electron, for example, behaves like a classical wave. In another, it behaves like a classical particle. Physicists can observe only one type of behaviour at a time, because there is no experiment that can be devised that could show both behaviours at once.
Bohr insisted that there is no contradiction in complementarity, because the use of these classical concepts is purely symbolic. This was not about whether electrons are really waves or particles. It was about accepting that physicists can never know what an electron really is and that they must reach for symbolic descriptions of waves and particles as appropriate. With these restrictions, Bohr regarded the theory to be complete — no further elaboration was necessary.
Such a pronouncement prompts an important question. What is the purpose of physics? Is its main goal to gain ever-more-detailed descriptions and control of phenomena, regardless of whether physicists can understand these descriptions? Or, rather, is it a continuing search for deeper and deeper insights into the nature of physical reality?
What does “hard” mean here? What does “illusory” mean here? Why does it matter whether everything is connected via a causal chain? Are any of those problems even problems?
Such has been my experience. Do you have a different experience?
What about a low-intensity double slit experiment, where each impact on the screen happens in exactly one spot, as if a particle was impacting that spot, but accumulating a high number of such impacts reveals an interference pattern like what only waves do? That this would happen with electrons is fairly common knowledge, since electron beam particle density is already low enough to resolve individual impacts, at least with the sort of materials and energies you would find in more common setups. Cathode ray tubes come to mind. Light beams are much denser at the same energies, and attenuating them down and also being able to record individual events is the greater challenge, but has been done, and shows the same behaviour. Does repeating an experiment or merely waiting to collect more data count as performing an altogether different one?
A fair question, but not a new one, even in Bohr’s day. Newton himself, in an appendix to later editions of Principia, uttered the famous “hypotheses non fingo”, an early instrumentalist-like take shared by many of his successors, before and after the advent of quantum physics. It is not a scientific matter, so goes the sentiment, just what exactly things “are fundamentally” (in Newton’s case, it was concerning the ultimate source/nature of gravitation, which he said would have no impact on his theory, one way or the other). We may have opinions, strong or weak, about ontological matters, but at the end of the day, a scientific theory’s merits are in how well it matches and predicts data, and philosophical implications, if considered at all, are a secondary concern at most.
Whether the “shut up and calculate” mantra is a healthy way to approach uncomfortable questions may be a matter of dispute, and whether Bohr would consider it a charitable interpretation of his position I am comfortable leaving to his biographers. But it is, for better or worse, one take that’s rather easy to defend on pragmatic grounds, assuming the alternative might at worst be to waste one’s time in an arm chair, advancing no model with any practical implications, let alone applications.
Personally, I think there is value to be had from attempting interpretations beyond the mere quantitative predicting, in particular where it can open up novel questions the exploration of which can refine and expand current theories. If by “nature of physical reality” we mean something like how observable nature behaves, then sure enough, that is a matter of scientific inquiry. If however we mean by it some question about what things fundamentally, ontologically “are”, then, as much as it may interest us as people, even the scientists among us, I would still rather classify it as a philosophical question, what ever that entails.
Well, no, I guess, in the sense that arguing about such issues over millenia has resolved nothing.
Not according to the combatibilists. They believe an action can be determined, and still be free. But they manage to hold this belief by using the term “free will” to mean something other than what the libertarians do. So, in that sense, you are likely correct. All this debate and handwringing over how to define a term…
I think that analysis misses an important additional position. What would you call determinism (i.e. causality) plus quantum indeterminacy (assuming that there actually is such a thing)? Still no room for libertarian free will, though of course compatibilist free will is compatible with anything.
Yes. I’m talking about libertarian free will. @Giltil, see why we need that disambiguation?
Actually, the issue of free will, libertarian or otherwise, is of little concern to me. I am quite happy to bask in the subjective impression that I can choose among limited options. What I find utterly incomprehensible, unacceptable, unbelievable, is the idea of a clockwork universe - wind back to the beginning and exactly the same thing happens again. I think Epicurus had it about right.
ETA maybe a better link to Epicurus
Then I’m mystified as to why we’ve been going back and forth on a subject that doesn’t interest you.
Why do you find that incomprehensible, etc.? And in what way did Epicurus have it right? Now of course quantum indeterminacy would seem to be just the sort of thing you’re looking for, but how would that facilitate free will? Assuming you have enough interest to respond.
Yes. That’s why I’m baffled that Sabine Hossenfelder, for example, talks of superdeterminism.
The swerve. His idea seems a premonition of quantum indeterminacy.
That’s nice, but what does quantum indeterminacy have to do with free will, or whatever it is you’re actually interested in?
Okay but why are you baffled?
Casinos have determined they will make money.
Some of the most precise parameters in physics are probabilities.
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Will need to find time to watch the video you posted.
So you’re baffled, but you’re also baffled about why you’re baffled? Would it help to know that the video specifically states that superdeterminism or lack thereof has nothing whatsoever to do with free will?