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I tried to argue against superdeterminism the last time this came up and got a pile of downvotes because people mixed it up with determinism. And I see this is

by knzhou 7y ago

I tried to argue against superdeterminism the last time this came up and got a pile of downvotes because people mixed it up with determinism. And I see this is happening all over again in the comments below. I'm not even going to try this time, I'm just going to say to everybody reading this: superdeterminism is not at all the same thing as determinism. It is a far stronger assumption with far far more unintuitive consequences for our understanding of nature. If you're reading this and just thinking "superdeterminism is okay because there's no free will", then you've been suckered by this article into believing a massive oversimplification.

miltondts 7y ago
What is need is less arguing and more experimenting. That's how this will be resolved.
- willis936 7y ago
  No no, arguing is important. It lubricates an essential step in the scientific process. No one can design experiments, let alone predict results or even understand results, without understanding.
  - miltondts 7y ago
    Let me clarify. In this particular case there has been plenty of arguing already and no progress in more than 50 years. So I'm suggesting it is time to start experimenting more.
    - skosch 7y ago
      I've been partial to superdeterminism for a long time, but I have no idea how one would go about testing it. In fact, it seems as unfalsifiable as many-worlds or other theories. Do you have a suggestion?
      - miltondts 7y ago
        The kind of superdeterministic theories proposed by t'Hooft are falsifiable. From [0] "If engineers ever succeed in making such quantum computers, it seems to me that the CAT is falsified; no classical theory can explain quantum mechanics." By "such quantum computers" he means computers that can run Shor's algorithm. "...but factoring a number with millions of digits into its prime factors will not be possible – unless fundamentally improved classical algorithms turn out to exist." As for the author of the article I've never seen a clear proposal but it appears the idea is to do repeated measurements that display quantum effects while reducing noise as much as possible and check if there are deviations from quantum theory. EDIT: found a more concrete proposal http://backreaction.blogspot.com/2013/10/testing-conspiracy-theories.html http://backreaction.blogspot.com/2013/10/testing-conspiracy-... [0] - https://arxiv.org/abs/1405.1548 https://arxiv.org/abs/1405.1548
      - baddox 7y ago
        My understanding was that many-worlds could be tested experimentally if we were able to set up large objects in superpositions, and I thought that there is no reason to expect that it isn’t physically possible to do so (we just don’t know how at the moment).
        akvadrako 7y ago
        You can’t get any information from that because the main interpretations all make the same predictions from an outside perspective, which is what you’ll expect to see. Besides to put a person in a superposition may require a machine as large as the universe, so you get issues with the speed of light. The only way to test MWI is multiverse immortality - many worlds means you should expect to always have some future experience - there is no real death.
        GoblinSlayer 7y ago
        Some version of you will expect it, some versions won't.
        GoblinSlayer 7y ago
    - qayxc 7y ago
      The authors don't argue that there's not enough experiments, though. They argue it's wrong type of experiments that are conducted. To quote Dr. Hossenfelder directly: "In standard quantum mechanics the measurement outcomes will be non-correlated. In a superdeterministric hidden variables theory, they'll be correlated - provided you can make a case that the hidden variables don't change in between the measurements." [1] That last sentence is the catch here: in case the experiment fails to show any correlation, it can always be argued that the hidden variables changed for whatever reason. If the calculated theoretical boundaries (e.g. temperature & measurement time) are insufficient, there's still no way of telling systematic errors from falsifying the initial hypothesis. It's little details like this that theorists can hide behind while still shouting "Foul!" from the peanut gallery. Since experiments cost time, money, and pin down talent, research facilities need to be picky about what they test. "Because I like it." [2] is not the most compelling argument when trying to make your case ;) I wonder whether crowd-funding would work in this case... [1] https://backreaction.blogspot.com/2013/10/testing-conspiracy-theories.html https://backreaction.blogspot.com/2013/10/testing-conspiracy... [2] https://www.fetzer-franklin-fund.org/wp-content/uploads/2014/12/Hossenfelder-EmQM131.pdf https://www.fetzer-franklin-fund.org/wp-content/uploads/2014...
    - normalnorm 7y ago
      This has been the mainstream position for most of those 50 years. Working on the "foundations of physics", which is what you call "arguing" was considered disreputable and career-destroying for a long time. Read, for example, "Something Deeply Hidden" by Sean Caroll for more about this. A lot of really really smart people tried to solve this by experimenting more. It didn't work. It's time for philosophy again, and in my view, also to accept that the weirdness is not going away. Nature doesn't care about what we find weird or not.
    - GoblinSlayer 7y ago
      The progress is stiffled by belief that this is not a problem and there should be no arguing and no experimenting and everybody should shut up and calculate.
    - de_watcher 7y ago
      Superdeterminism says that arguing is a part of the experiment anyway.
- nwallin 7y ago
  You can't. Not just the way it's arbitrarily hard from an engineering perspective to design an experiment to disprove string theory. It is theoretically impossible, the way it's impossible to distinguish between Copenhagen and many worlds.
  - vilhelm_s 7y ago
    No, you actually can. The authors of this article discuss the issue more in their longer paper here: https://arxiv.org/abs/1912.06462 https://arxiv.org/abs/1912.06462 The idea is that superdeterminstic theories are deterministic, while quantum mechanical measurements are random, so you should be able to set up an experiment where QM predicts you would just get random results, but actually you get the same result each time.
    - bosswipe 7y ago
      There are many classical physics experiments you could do where you understand all the physics and formulas to excruciating detail and you control every variable but you still can't get the same results everytime. Things like throwing dice, as mentioned in the article, or the chaos generated by flowing fluids. Given that any superdeterministic mechanisms would be even even more complex and weird and unknown it seems impossible to disprove. Any failed experiment could be excused by saying that there are more unknown uncontroled variables.
      - zelphirkalt 7y ago
        Well, the determinist would argue, that, if you cannot predict the result reliably every time, you do not actually know all the variables, even if you think you do.
    - GoblinSlayer 7y ago
      Setting up such an experiment means to control hidden variables, but then they aren't hidden.
      - 7y ago
xnxn 7y ago
Here's that previous discussion, for the curious. https://news.ycombinator.com/item?id=21802674 https://news.ycombinator.com/item?id=21802674
wwarner 7y ago
I really agree with you here. Superdeterminism is much weirder and harder to accept than non-locality. Of course, with enough non-locality you'll end up with something just as awkward as superdeterminism. I'm trying learn more about decoherence as an alternative to wave-function collapse. I'm listening to the Into to QM course from mit's open courseware [0] and I have to say that QM represents a complete break with the classical past, not because of a scientist's ambition or a quirk of history, but because the experimental evidence demands it. The evidence results in a few postulates, and QM is really the only theory that satisfies the postulates, in the sense that any theory that satisfies those postulates will look like Schroedinger's eq. The story is not over at all, we're still very much at the beginning of understanding it. [0] https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-spring-2013/ https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-s...
- remcob 7y ago
  To me decoherence always seemed so obviously the solution to these 'problems in QM' that I genuinely don't understand why are still having these quasi-scientific discussions. Am I missing something or is there a ton of uninformed arm-chair science going on? What are the scientific arguments against decoherence? What do up-to-date theoreticians think?
  - akvadrako 7y ago
    No mainstream physicist really objects to decoherence - it is obvious. But just decoherence doesn’t give you single outcomes - it gives you many worlds. And people do debate how to derive our single world experience from many worlds. It can’t be done without more assumptions. Many in this field do accept it, but say the other worlds are not real (QBism, dBB). But that position is philosophically weak, so those against many worlds still look for alternatives.
    - whatshisface 7y ago
      I think when you add in the word "experience" you turn the physics problem into a philosophical one, and every pragmatic scientist wanders off to work on something else. Many worlds is totally sufficient for every question except for the nature of consciousness, and there are some very good reasons to believe that consciousness is non-empirical.
gammadens 7y ago
I see the difference between determinism and superdeterminism but it's unclear to me why, if you accept the former, why you might not accept the latter. I think it's worth thinking through and delineating superdeterminism to its utmost limits even if I wouldn't necessarily say I find it compelling. I do wonder why the authors are so quick to reject nonreductionism though, as nonreductionism seems fairly reasonable to me. Maybe I have a different idea of nonreductionism, but it seems to me that rejecting nonreductionism is akin to accepting Laplace's demon which as far as I understand has been disproved. Basically, at some point the information in a system supercedes that of any system that might represent it faithfully, in part because of measurement effects -- there's a lot of parallels with QM issues.
jacobwilliamroy 7y ago
What even is superdeterminism? Determined determinism? What?
TheOtherHobbes 7y ago
The problem is determining what determinism determines and how it determines it. And that's a precondition before you can even consider superdeterminism. There is nothing in classical physics that suggests the universe is deterministic on cosmic scales. There's plenty in physics which suggests it isn't. If you want to propose any form of determinism, be it superdeterminism, a bulk universe, or any of the other popular variations, you have to start by proving that causality is infinitely precise and absolute. Because otherwise your causality is partly random and therefore not truly causal at all. Our experience of causality suggests that real measurements have limited precision, and predictions can only be made on limited timescales. So anyone who is proposing superdeterminism is claiming that this can be fixed - by hidden variables, with noise-free super-realistic precision, which allow a universe-wide predictive horizon. Free will is a side issue here, because the problem doesn't go away even if the universe has no observers. The problem isn't whether free will hides super-predictive hidden variables, it's whether it's plausible that super-predictive hidden variables exist at all. If you believe they do, you have a first-order universe in which these mysterious entities operate with effectively infinite precision behind the scenes, to create a second-order universe which has limited precision in practice. Of course that may be happening. But it seems like quite unlikely.
- The_rationalist 7y ago
  You believe that magic ad-hoc random variables are more plausible? And that somehow for whatever non-causal (so magic) reason they follow the same probability distribution? This is clearly epistemologically weaker, but seduce more the wishful thinker mind.
  - birdyrooster 7y ago
    I think for these people the detail just doesn't matter to them. They see near random behavior which is currently impossible to model and they shrug their shoulders and call it a magic, ad-hoc random variable. And to a degree, they have a point: Does it really matter if we can predict the exact time and location of an alpha particle as is exits a black hole as hawking radiation? What good does modeling this phenomenon accurately give us?
Rury 7y ago
Determinism simply means the nature of things is deterministic, that's all. In other words, that is: given all initial conditions you can determine the exact resulting conditions. Bell coined the term "Superdeterminism" to describe to others of theories that evade his own theorem - theories which are absolutely and completely deterministic. Theories that are only partially deterministic - don't hold up to his theorem. Hence he coined this term to highlight the difference (to those that fail to understand), which again is absolutely/completely vs partially deterministic theories. As so there's no real difference here. If you understand determinism, then you know that a "partially" deterministic theory is not actually deterministic...
fpoling 7y ago
Yep. Superdeterminism as a particular physical hypothesis has nothing to do with a philosophical notion of determinism or debates about free will. The latter is really the subject of metaphysics which by definition is not physics. It is like mixing implementation details of a particular Python script with a theory of programming languages.
- zelphirkalt 7y ago
  Someone who knows, that determinism can be a metaphysical concept (depending on which determinism one is talking about). Not many people get that. Good to see some people actually read about it or thought about it. This is what I always try to explain to people trying to counter it with quantum mechanics, as if it was a proof against determinism.
  - feanaro 7y ago
    I'm interested. Could you expand a bit more on this? You imply there are different types (levels?) of determinism. Which are those?
    - fpoling 7y ago
      I can try for grandparent. In physics all equations including quantum mechanics are deterministic in the sense that if one knows the initial state of the universe then one knows evolution of the universe after and before. Moreover, in classical physics the assumption was that if one knows the state of some local patch of the universe at some moment, then one in principle can tell the near future and past of that local patch without knowing the state of the rest of the universe. Experimental observations of violations of Bell equations tell that no, one cannot tell the evolution of the local patch from the patch alone. Standard interpretation of quantum mechanics and physical super-determinism are just different ways to explain this. In particular the standard quantum mechanics assumes that things are still local, but the wave function is not observable in principle so we can only talk about statistical properties. Super-determinisme assumes that things are not local and tries to explain how. In philosophy determinism is essentially the opposite of free will. It implies that what people perceive as personal free will is an illusion. But this has nothing to do with the determinism of physical models. In particular, free will is compatible with physical determinism of what one perceives as an external world. One possible explanation of how this is possible is that the act of free will changes both future and past. So it looks like the future state reflecting the choice of will is deterministically follows from the past. It is just the past is different from what would be if the choice would be different. Stanford encyclopedia entry on free will has more splendid explanations.
moh_maya 7y ago
"The implications of superdeterminism, if it is true, would bring into question the value of science itself by destroying falsifiability, as Anton Zeilinger has commented" [1] [1] https://en.m.wikipedia.org/wiki/Superdeterminism https://en.m.wikipedia.org/wiki/Superdeterminism
- jayd16 7y ago
  These criticism sound quite convoluted and hyperbolic when its really just saying some kind of intrinsic selection bias is a possible explanation.
- GoblinSlayer 7y ago
  A simple description of superdeterminism would be that it's a theory of hidden variables where those hidden variables evolve with intelligence level complexity. It's a traditional method to evade falsifiability, yes :)
- naasking 7y ago
  > The implications of superdeterminism, if it is true, would bring into question the value of science itself by destroying falsifiability, as Anton Zeilinger has commented Except Zeilinger is wrong. The freedom of the experimenter is not fundamental to the scientific process, rather the nature of the experimenter's complexity is what matters. Even simple deterministic algorithms can explore an entire state space, and given we are capable of simulating such algorithms with our brains (Turing completeness), we are therefore also capable of exploring the full state space of physical theories. Furthermore, it is not a false picture of nature at all. It very clearly describes the behaviour of that which is observable, which is exactly what science is designed to do.
juped 7y ago
I think of superdeterminism not as a theory but as a barometer - the Bell's Theorem world we live in is baffling enough that people are willing to consider superdeterminism as an explanation.
montjoy 7y ago
I was curious so I looked up your comments. > There is no such thing as a controlled experiment > The superdeterministic explanation is: "well, there's nothing to explain. You were simply determined to lose by the initial conditions of the universe. It couldn't have gone any other way." This eventually led me to a quote from Anton Zeilinger about his dislike for it. > I suggest, it would make no sense at all to ask nature questions in an experiment, since then nature could determine what our questions are, and that could guide our questions such that we arrive at a false picture of nature. My question is, does it matter if we are seeing a false picture as long as the result of experiments within it are consistent and lead to new discoveries that themselves are actionable? If everything we experience is in this “false picture” is it really false or simply a different set of rules based on underlying circumstances. I think the whole point being made by the authors here is that QM is dead-ending and that superdeterminism could give us more answers, not less. Why not see if it leads somewhere?
- GoblinSlayer 7y ago
  first discoveries were done without a sound theory, it's certainly possible :) >authors here is that QM is dead-ending Copenhagen is dead-ending, not QM.
- de_watcher 7y ago
  Superdeterminism is like the whole existence being a Haskell program without I/O. To get anything actionable we'll have to logically separate parts of it...
pjs_ 7y ago
Agreed. This line: > But because of the historical legacy, researchers who have worked on or presently work on Superdeterminism have been either ignored or ridiculed. is too strong. I would say that the historical legacy does not have much to do with it - the reason that superdeterminism is ignored or ridiculed is that it looks absolutely wild to most physicists - much more mind-bending than the vanilla story of the Bell test, which is mad enough to begin with. That's not to say that it is ruled out - just that we have avoided it for pretty sensible reasons, rather than stupidity or some sort of blind spot.
- naasking 7y ago
  > That's not to say that it is ruled out - just that we have avoided it for pretty sensible reasons, rather than stupidity or some sort of blind spot. I have to question the validity of this argument, because generations of physicists have been taught to give up realism in order to accept QM. Superdeterminism is no weirder than giving up realism, it's just a weirdness to which you've grown accustomed.
Decoherent 7y ago
In general all these interpretations are more popular on the technically literate web going culture than in actual research in physics where Copenhagen style views still predominate. For the simple reason that all of the other interpretations (Many Worlds, Bohmian, Transactional) only somewhat work with Non-Relativistic QM not with QFT. Only Copenhagen works with QFT.

by knzhou 7y ago

miltondts 7y ago

What is need is less arguing and more experimenting. That's how this will be resolved.

willis936 7y ago
No no, arguing is important. It lubricates an essential step in the scientific process. No one can design experiments, let alone predict results or even understand results, without understanding.
- miltondts 7y ago
  Let me clarify. In this particular case there has been plenty of arguing already and no progress in more than 50 years. So I'm suggesting it is time to start experimenting more.
  - skosch 7y ago
    I've been partial to superdeterminism for a long time, but I have no idea how one would go about testing it. In fact, it seems as unfalsifiable as many-worlds or other theories. Do you have a suggestion?
    - miltondts 7y ago
      The kind of superdeterministic theories proposed by t'Hooft are falsifiable. From [0] "If engineers ever succeed in making such quantum computers, it seems to me that the CAT is falsified; no classical theory can explain quantum mechanics." By "such quantum computers" he means computers that can run Shor's algorithm. "...but factoring a number with millions of digits into its prime factors will not be possible – unless fundamentally improved classical algorithms turn out to exist." As for the author of the article I've never seen a clear proposal but it appears the idea is to do repeated measurements that display quantum effects while reducing noise as much as possible and check if there are deviations from quantum theory. EDIT: found a more concrete proposal http://backreaction.blogspot.com/2013/10/testing-conspiracy-theories.html http://backreaction.blogspot.com/2013/10/testing-conspiracy-... [0] - https://arxiv.org/abs/1405.1548 https://arxiv.org/abs/1405.1548
    - baddox 7y ago
      My understanding was that many-worlds could be tested experimentally if we were able to set up large objects in superpositions, and I thought that there is no reason to expect that it isn’t physically possible to do so (we just don’t know how at the moment).
      - akvadrako 7y ago
        You can’t get any information from that because the main interpretations all make the same predictions from an outside perspective, which is what you’ll expect to see. Besides to put a person in a superposition may require a machine as large as the universe, so you get issues with the speed of light. The only way to test MWI is multiverse immortality - many worlds means you should expect to always have some future experience - there is no real death.
        GoblinSlayer 7y ago
        Some version of you will expect it, some versions won't.
      - GoblinSlayer 7y ago
  - qayxc 7y ago
    The authors don't argue that there's not enough experiments, though. They argue it's wrong type of experiments that are conducted. To quote Dr. Hossenfelder directly: "In standard quantum mechanics the measurement outcomes will be non-correlated. In a superdeterministric hidden variables theory, they'll be correlated - provided you can make a case that the hidden variables don't change in between the measurements." [1] That last sentence is the catch here: in case the experiment fails to show any correlation, it can always be argued that the hidden variables changed for whatever reason. If the calculated theoretical boundaries (e.g. temperature & measurement time) are insufficient, there's still no way of telling systematic errors from falsifying the initial hypothesis. It's little details like this that theorists can hide behind while still shouting "Foul!" from the peanut gallery. Since experiments cost time, money, and pin down talent, research facilities need to be picky about what they test. "Because I like it." [2] is not the most compelling argument when trying to make your case ;) I wonder whether crowd-funding would work in this case... [1] https://backreaction.blogspot.com/2013/10/testing-conspiracy-theories.html https://backreaction.blogspot.com/2013/10/testing-conspiracy... [2] https://www.fetzer-franklin-fund.org/wp-content/uploads/2014/12/Hossenfelder-EmQM131.pdf https://www.fetzer-franklin-fund.org/wp-content/uploads/2014...
  - normalnorm 7y ago
    This has been the mainstream position for most of those 50 years. Working on the "foundations of physics", which is what you call "arguing" was considered disreputable and career-destroying for a long time. Read, for example, "Something Deeply Hidden" by Sean Caroll for more about this. A lot of really really smart people tried to solve this by experimenting more. It didn't work. It's time for philosophy again, and in my view, also to accept that the weirdness is not going away. Nature doesn't care about what we find weird or not.
  - GoblinSlayer 7y ago
    The progress is stiffled by belief that this is not a problem and there should be no arguing and no experimenting and everybody should shut up and calculate.
  - de_watcher 7y ago
    Superdeterminism says that arguing is a part of the experiment anyway.
nwallin 7y ago
You can't. Not just the way it's arbitrarily hard from an engineering perspective to design an experiment to disprove string theory. It is theoretically impossible, the way it's impossible to distinguish between Copenhagen and many worlds.
- vilhelm_s 7y ago
  No, you actually can. The authors of this article discuss the issue more in their longer paper here: https://arxiv.org/abs/1912.06462 https://arxiv.org/abs/1912.06462 The idea is that superdeterminstic theories are deterministic, while quantum mechanical measurements are random, so you should be able to set up an experiment where QM predicts you would just get random results, but actually you get the same result each time.
  - bosswipe 7y ago
    There are many classical physics experiments you could do where you understand all the physics and formulas to excruciating detail and you control every variable but you still can't get the same results everytime. Things like throwing dice, as mentioned in the article, or the chaos generated by flowing fluids. Given that any superdeterministic mechanisms would be even even more complex and weird and unknown it seems impossible to disprove. Any failed experiment could be excused by saying that there are more unknown uncontroled variables.
    - zelphirkalt 7y ago
      Well, the determinist would argue, that, if you cannot predict the result reliably every time, you do not actually know all the variables, even if you think you do.
  - GoblinSlayer 7y ago
    Setting up such an experiment means to control hidden variables, but then they aren't hidden.
    - 7y ago

xnxn 7y ago

Here's that previous discussion, for the curious. https://news.ycombinator.com/item?id=21802674 https://news.ycombinator.com/item?id=21802674

wwarner 7y ago

I really agree with you here. Superdeterminism is much weirder and harder to accept than non-locality. Of course, with enough non-locality you'll end up with something just as awkward as superdeterminism. I'm trying learn more about decoherence as an alternative to wave-function collapse. I'm listening to the Into to QM course from mit's open courseware [0] and I have to say that QM represents a complete break with the classical past, not because of a scientist's ambition or a quirk of history, but because the experimental evidence demands it. The evidence results in a few postulates, and QM is really the only theory that satisfies the postulates, in the sense that any theory that satisfies those postulates will look like Schroedinger's eq. The story is not over at all, we're still very much at the beginning of understanding it. [0] https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-spring-2013/ https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-s...

remcob 7y ago
To me decoherence always seemed so obviously the solution to these 'problems in QM' that I genuinely don't understand why are still having these quasi-scientific discussions. Am I missing something or is there a ton of uninformed arm-chair science going on? What are the scientific arguments against decoherence? What do up-to-date theoreticians think?
- akvadrako 7y ago
  No mainstream physicist really objects to decoherence - it is obvious. But just decoherence doesn’t give you single outcomes - it gives you many worlds. And people do debate how to derive our single world experience from many worlds. It can’t be done without more assumptions. Many in this field do accept it, but say the other worlds are not real (QBism, dBB). But that position is philosophically weak, so those against many worlds still look for alternatives.
  - whatshisface 7y ago
    I think when you add in the word "experience" you turn the physics problem into a philosophical one, and every pragmatic scientist wanders off to work on something else. Many worlds is totally sufficient for every question except for the nature of consciousness, and there are some very good reasons to believe that consciousness is non-empirical.

gammadens 7y ago

I see the difference between determinism and superdeterminism but it's unclear to me why, if you accept the former, why you might not accept the latter. I think it's worth thinking through and delineating superdeterminism to its utmost limits even if I wouldn't necessarily say I find it compelling. I do wonder why the authors are so quick to reject nonreductionism though, as nonreductionism seems fairly reasonable to me. Maybe I have a different idea of nonreductionism, but it seems to me that rejecting nonreductionism is akin to accepting Laplace's demon which as far as I understand has been disproved. Basically, at some point the information in a system supercedes that of any system that might represent it faithfully, in part because of measurement effects -- there's a lot of parallels with QM issues.

jacobwilliamroy 7y ago

What even is superdeterminism? Determined determinism? What?

TheOtherHobbes 7y ago

The problem is determining what determinism determines and how it determines it. And that's a precondition before you can even consider superdeterminism. There is nothing in classical physics that suggests the universe is deterministic on cosmic scales. There's plenty in physics which suggests it isn't. If you want to propose any form of determinism, be it superdeterminism, a bulk universe, or any of the other popular variations, you have to start by proving that causality is infinitely precise and absolute. Because otherwise your causality is partly random and therefore not truly causal at all. Our experience of causality suggests that real measurements have limited precision, and predictions can only be made on limited timescales. So anyone who is proposing superdeterminism is claiming that this can be fixed - by hidden variables, with noise-free super-realistic precision, which allow a universe-wide predictive horizon. Free will is a side issue here, because the problem doesn't go away even if the universe has no observers. The problem isn't whether free will hides super-predictive hidden variables, it's whether it's plausible that super-predictive hidden variables exist at all. If you believe they do, you have a first-order universe in which these mysterious entities operate with effectively infinite precision behind the scenes, to create a second-order universe which has limited precision in practice. Of course that may be happening. But it seems like quite unlikely.

The_rationalist 7y ago
You believe that magic ad-hoc random variables are more plausible? And that somehow for whatever non-causal (so magic) reason they follow the same probability distribution? This is clearly epistemologically weaker, but seduce more the wishful thinker mind.
- birdyrooster 7y ago
  I think for these people the detail just doesn't matter to them. They see near random behavior which is currently impossible to model and they shrug their shoulders and call it a magic, ad-hoc random variable. And to a degree, they have a point: Does it really matter if we can predict the exact time and location of an alpha particle as is exits a black hole as hawking radiation? What good does modeling this phenomenon accurately give us?

Rury 7y ago

Determinism simply means the nature of things is deterministic, that's all. In other words, that is: given all initial conditions you can determine the exact resulting conditions. Bell coined the term "Superdeterminism" to describe to others of theories that evade his own theorem - theories which are absolutely and completely deterministic. Theories that are only partially deterministic - don't hold up to his theorem. Hence he coined this term to highlight the difference (to those that fail to understand), which again is absolutely/completely vs partially deterministic theories. As so there's no real difference here. If you understand determinism, then you know that a "partially" deterministic theory is not actually deterministic...

fpoling 7y ago

Yep. Superdeterminism as a particular physical hypothesis has nothing to do with a philosophical notion of determinism or debates about free will. The latter is really the subject of metaphysics which by definition is not physics. It is like mixing implementation details of a particular Python script with a theory of programming languages.

zelphirkalt 7y ago
Someone who knows, that determinism can be a metaphysical concept (depending on which determinism one is talking about). Not many people get that. Good to see some people actually read about it or thought about it. This is what I always try to explain to people trying to counter it with quantum mechanics, as if it was a proof against determinism.
- feanaro 7y ago
  I'm interested. Could you expand a bit more on this? You imply there are different types (levels?) of determinism. Which are those?
  - fpoling 7y ago
    I can try for grandparent. In physics all equations including quantum mechanics are deterministic in the sense that if one knows the initial state of the universe then one knows evolution of the universe after and before. Moreover, in classical physics the assumption was that if one knows the state of some local patch of the universe at some moment, then one in principle can tell the near future and past of that local patch without knowing the state of the rest of the universe. Experimental observations of violations of Bell equations tell that no, one cannot tell the evolution of the local patch from the patch alone. Standard interpretation of quantum mechanics and physical super-determinism are just different ways to explain this. In particular the standard quantum mechanics assumes that things are still local, but the wave function is not observable in principle so we can only talk about statistical properties. Super-determinisme assumes that things are not local and tries to explain how. In philosophy determinism is essentially the opposite of free will. It implies that what people perceive as personal free will is an illusion. But this has nothing to do with the determinism of physical models. In particular, free will is compatible with physical determinism of what one perceives as an external world. One possible explanation of how this is possible is that the act of free will changes both future and past. So it looks like the future state reflecting the choice of will is deterministically follows from the past. It is just the past is different from what would be if the choice would be different. Stanford encyclopedia entry on free will has more splendid explanations.

moh_maya 7y ago

"The implications of superdeterminism, if it is true, would bring into question the value of science itself by destroying falsifiability, as Anton Zeilinger has commented" [1] [1] https://en.m.wikipedia.org/wiki/Superdeterminism https://en.m.wikipedia.org/wiki/Superdeterminism

jayd16 7y ago
These criticism sound quite convoluted and hyperbolic when its really just saying some kind of intrinsic selection bias is a possible explanation.
GoblinSlayer 7y ago
A simple description of superdeterminism would be that it's a theory of hidden variables where those hidden variables evolve with intelligence level complexity. It's a traditional method to evade falsifiability, yes :)
naasking 7y ago
> The implications of superdeterminism, if it is true, would bring into question the value of science itself by destroying falsifiability, as Anton Zeilinger has commented Except Zeilinger is wrong. The freedom of the experimenter is not fundamental to the scientific process, rather the nature of the experimenter's complexity is what matters. Even simple deterministic algorithms can explore an entire state space, and given we are capable of simulating such algorithms with our brains (Turing completeness), we are therefore also capable of exploring the full state space of physical theories. Furthermore, it is not a false picture of nature at all. It very clearly describes the behaviour of that which is observable, which is exactly what science is designed to do.

juped 7y ago

I think of superdeterminism not as a theory but as a barometer - the Bell's Theorem world we live in is baffling enough that people are willing to consider superdeterminism as an explanation.

montjoy 7y ago

I was curious so I looked up your comments. > There is no such thing as a controlled experiment > The superdeterministic explanation is: "well, there's nothing to explain. You were simply determined to lose by the initial conditions of the universe. It couldn't have gone any other way." This eventually led me to a quote from Anton Zeilinger about his dislike for it. > I suggest, it would make no sense at all to ask nature questions in an experiment, since then nature could determine what our questions are, and that could guide our questions such that we arrive at a false picture of nature. My question is, does it matter if we are seeing a false picture as long as the result of experiments within it are consistent and lead to new discoveries that themselves are actionable? If everything we experience is in this “false picture” is it really false or simply a different set of rules based on underlying circumstances. I think the whole point being made by the authors here is that QM is dead-ending and that superdeterminism could give us more answers, not less. Why not see if it leads somewhere?

GoblinSlayer 7y ago
first discoveries were done without a sound theory, it's certainly possible :) >authors here is that QM is dead-ending Copenhagen is dead-ending, not QM.
de_watcher 7y ago
Superdeterminism is like the whole existence being a Haskell program without I/O. To get anything actionable we'll have to logically separate parts of it...

pjs_ 7y ago

Agreed. This line: > But because of the historical legacy, researchers who have worked on or presently work on Superdeterminism have been either ignored or ridiculed. is too strong. I would say that the historical legacy does not have much to do with it - the reason that superdeterminism is ignored or ridiculed is that it looks absolutely wild to most physicists - much more mind-bending than the vanilla story of the Bell test, which is mad enough to begin with. That's not to say that it is ruled out - just that we have avoided it for pretty sensible reasons, rather than stupidity or some sort of blind spot.

naasking 7y ago
> That's not to say that it is ruled out - just that we have avoided it for pretty sensible reasons, rather than stupidity or some sort of blind spot. I have to question the validity of this argument, because generations of physicists have been taught to give up realism in order to accept QM. Superdeterminism is no weirder than giving up realism, it's just a weirdness to which you've grown accustomed.

Decoherent 7y ago

In general all these interpretations are more popular on the technically literate web going culture than in actual research in physics where Copenhagen style views still predominate. For the simple reason that all of the other interpretations (Many Worlds, Bohmian, Transactional) only somewhat work with Non-Relativistic QM not with QFT. Only Copenhagen works with QFT.