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Arguments Against Superdeterminism

  1. Aug 1, 2009 #1
    In the context of Bell's Theorem, a superdeterministic theory would negate the statistical independence between the source generating the entangled particles and the detectors. IMHO there is nothing absurd about this. There are plenty of examples in physics where the motion of two distant objects presents correlations (this includes all objects that are accompanied by long-range fields).

    Nevertheless, superdeterminism (SD) is seldom even mentioned as a possibility and usually dismissed. I would like to see a clear statement of the arguments against SD and see how founded they are.
  2. jcsd
  3. Aug 1, 2009 #2
    I think Superdeterminism invites the "Supernatural". There is similar talk in the philosophy forum, so i'll copy-paste what i stated there:

    "A purely deterministic "mind" as a determinite consequence of a brain in a determinite universe requires the Supernatural. If we do not have free will, who willfully created my celluar phone, if it was not the will of the engineers at Nokia? Whose will was that? Who created the LHC collider and the beer i've just opened? How could any of those things exist if "we" did not willfully created them? How would we provide explanation who did?"

    And Superdeterminism involves absolute determinism in the universe, the complete absence of free will.
    Last edited: Aug 1, 2009
  4. Aug 1, 2009 #3
    What is the difference between a cell phone and a rock at a fundamental level? There are the same type of particles following the same physical laws. The question "Who created the LHC collider...", and all other, are loaded, they presuppose the necessity of an entity with free will. My answer is that, all objects (including a cell phone and a rock) appear in the same way, through interactions between the same type of particles following the same physical laws. I have seen no evidence for the contrary. If you know of such evidence I'd like to see it.

    A difference only exists at the macroscopic level because some objects have significance for us. To make an analogy, do you think there is any fundamental difference between a group of stars resembling a lion or a fish and any other random group of stars?

    What is supernatural about a cell phone?
  5. Aug 1, 2009 #4

    Thought provoking theory, really. True but incomplete IMO. It does not even begin to address the reason for the illusory existence of a classical world(even if it makes sense only to us). And why is there the illusion of "us", superdeterminism cannot explain this and neither can QM. A purely quantum picture of the universe cannot explain everything that we've found to exist, because a large ensemble of particles do not always behave in the same way as the individual ones that comprise them. Hence a TOE is supposed to account for both the quantum and the classical level of bahaviour.

    Yes of course. If the group that resembles the lion begins to collectively behave like a Lion and starts hunting for zebras made up of other stars(i.e. the atoms of the stars that are considered to be a lion move intentionally all the way to the atoms that comprise zebras).
    The classical level exists even if it's just a shadow and it needs an explanation. Without free-will this explanation screams "Supernatural".

    The idea of a cell phone in a superdeterministic universe with no free will or some form of higher intelligence is mind-bending.
    Last edited: Aug 1, 2009
  6. Aug 1, 2009 #5
    I see no evidence that the human brain does not obey QM. IMHO there is only a computational problem. I doubt that QM is even required as I don't buy Penrose's theory about microtubules. AFAIK the brain is fully into the classical regime. What is your evidence that the brain somehow eludes QM? Also, this is not an argument against SD as SD is supposed to explain why QM works as it does.

    Of course, the behaviour of a composite object is different from the behaviour of its parts. However, in theory you can calculate the evolution of a complex object if you know its constituents. It is a computational problem.

    Sure, as long as the computational power permits it.

    Well, this is another type of lion. One that doesn't hunt.:biggrin:

    I failed to see how the classical world requires "free-will" in order to be explained. Again do you have some evidence for this assertion? To be a little constructive, animals are genetically programmed to react in certain ways. You do not need "free-will" to explain their behaviour.

    Sorry, but this is not an argument at all.
  7. Aug 1, 2009 #6

    I am putting great efforts into seeing the world as you see it and my head is spinning. What is "we" in this "universe" of yours? Your theory does not answer the question - if everything is an illusion, what causes it? Or is the existence of illusion also an illusion? I assume you see the classical world as a movie embedded in dumb quantum fields, where fields interact to produce the illusion of self. If this is so, what makes us try and explain this weird reality(why would a robot try and explain itself if it didn't have free will or wasn't programmed to do so?

    Yes, right!!! Genetically programmed is the right term for your vision of the universe. If there is no randomness, even the theory of evolution must abandon the idea of random mutations. If they are not random, i think you know where that leads...

    Why are we explaining anything in a superdeterministic universe at all? Was the Big Bang preprogrammed so that our shadow classical reality would appear out of quantum fields interactions, where we would have the illusion of asking questions about our illusiory existence? How is this supposed to work without a creator? Simply put, what causes the appearance of existence of cell phones in superdeterministic universes? What could explain our personal subjective experience of reality? Some event in the past? What is this event?

    How do you explain the fact that you don't have free will, yet you've come to realise that you never had free will? Was this event(the realisation) pre-programmmed?
    Last edited: Aug 1, 2009
  8. Aug 1, 2009 #7
    It's not clear to me what you mean by this.

    Considering a simple optical Bell setup (emitter, two polarizing filters, and two photon detectors), I assume that you mean "the source generating the entangled particles" to refer to the polarizers.

    There's a predictable relationship between joint polarizer settings and joint detection rates -- and the pairing process produces statistical dependence between the sets of separately accumulated detection attributes.

    What statistical independence are you referring to?

    As far as I can tell, the term, superdeterminism, is semantically equivalent to the term, determinism.

    All of physical science, whether one is searching for dynamical rules/laws specific to an emergent regime/scale or fundamental to and pervading everything, is based on the assumption of determinism.

    Unfortunately, by itself, it doesn't explain anything.

    Or am I completely missing your point?

    What might superdeterminism, or absolute determinism, etc. refer to that determinism doesn't already refer to?
  9. Aug 1, 2009 #8


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    SD is not science anymore than belief in God is.

    Unless of course you postulate a specific theory which shows how different forces - let's say the weak and the electromagnetic - have heretofor unknown connections. Let's say we use radioactive decay to make the decision to set polarizar settings in a Bell test in which the detectors are separated (sufficiently that they are outside of each other's light cones). The superdeterministic theory will require that the decay be coordinated so that the results can be properly correlated per Malus. That's a tall order! Ditto for any possible selection mechanism. You need all experimental apparati - regardless of setup - to conspire.

    So where is the science here?
  10. Aug 1, 2009 #9
    John Bell on the BBC:
    From this I think it's clear that superdeterminism, absolute determinism, universal determinism and determinism are synonymous.

    How does the assumption of determinism, which underlies physical science anyway, obviate the assumption of nonlocality?

    How is determinism an alternative to quantum probability, quantum superposition, and quantum state vector reduction?
    Last edited: Aug 1, 2009
  11. Aug 3, 2009 #10
    I think if Superdeterminism could possibly be a loophole, I think it should be looked at more closely, if only as a way around FTL communication. In certain respects it makes sense: why should the experimenter (or any human for that matter) be free or separate from which he/her came. I mean don't we develop and make our way in the world through our biology, genetic make-up, physiology, bio-physics, evolution of brain, etc... If true, then it seems our behavior is a result of all of these variables as well. Where exactly does the human brain separate itself from all of these factors, and become "free" to conduct whatever set up he chooses in experiments. Some of the Eastern religions take on this Superdeterminism approach to understanding the world. If nothing else, it should at least be considered and discussed.
  12. Aug 3, 2009 #11


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    To me, the question is not wether I can 100% disproove determinism or superdeterminism - I can't, the question is what predictive advantages does it give us?

    As I see it, the determinism attemps are more motivated by secret desires to restore more realism. But I do not see any motivation for this from the point of view of scientific inquiry.

    I only see disadvantages since it's encourages to a particular realistic type of reasoning, that I personally find inhibiting.

  13. Aug 3, 2009 #12
    We are large groups of (mainly) quarks and electrons.

    I didn't say that "everything is an illusion". How exactly our brain works is not a QM question. On the other hand I have seen no evidence that the brain should deserve a different treatment than any other object.

    We try to explain the world around us because we are genetically programmed to do so (it enhances survival).

    Evolution does not require that mutations are fundamentally random (unpredictable in principle). The term "random mutation" refers to our lack of knowledge regarding the exact conditions at the time that mutation occurred. So there is no conflict between a deterministic universe and evolution.

    Those questions can be also put in a probabilistic universe. The fact that some quantum events might be unpredictable do not explain any of your above questions therefore I think they have no relevance to our topic. Give me a good account of how "our personal subjective experience of reality" appears in a universe that is not superedetrministic.

    The existent evidence pointed me into that direction. I don't think it was "pre-programmed". It could be predicted by someone with infinite knowledge but this is different.
  14. Aug 3, 2009 #13
    No, I refer to the emitter (PDC crystal for example). Bell's theorem requires that the properties of the entangled particles (say spin) do not depend on the state of the detectors. A superdeterministic theory would deny this. As an example, assume that the emission is "stimulated" by a field coming from the detectors and the spin of the entangled particles is related to the value of this field. But because the evolution is deterministic, this field uniquely determines the future state of the detectors, therefore the spin of the entangled particles and the detector settings at the time of detection are not independent variables.

    I agree. I use the term (invented by Bell, I think) in order to point out that a separation between the system and observer is not possible. Such a separation might be possible in certain deterministic theories.

    I also agree.

    It can explain a lot of things. Correlations that are supposed to appear as a result of non-local effects can be explained by a past common cause + deterministic evolution. A probabilistic theory wouldn't allow for that.

    See above.
  15. Aug 3, 2009 #14
    The separation of the weak and electromagnetic forces is AFAIK not believed to be fundamental anymore. A Nobel price has been given for contribution to the unification of the two forces (see the Wiki article for "Electroweak interaction"). So your comments are about 30 years outdated. If you agree that string theory is science (not a belief in a god) then you would also agree that, at a fundamental level all known physics is based on a single object, a string, and a unique set of laws. Seen from this perspective there is realy not much of a difference between different types of experimental setups (computer random generators, brains, radioactive decay, etc). If the time evolution of a string is deterministic then all known objects have a predictable behavior as well, regardless of their macroscopic appearance.

    About the "conspiracy" accusations you should also claim that the energy conservation principle is not scientiffic because it applies to all systems (involving any known forces or mixtures of them).
  16. Aug 3, 2009 #15
    Deterministic hidden variable theories are a class of theories that has not been explored. They might lead to a better understanding of QM, possibly to new experimental predictions.

    I think the science as we know it exists because of this "inhibiting type of reasoning". I see no disadvantage in restoring a well mathematical defined, deterministic and local theory at a fundamental level.
  17. Aug 3, 2009 #16


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    If you have the motivation to explore that, I see no good reason why you shouldn't of course. But to me, searching for deterministic and realist type theories isn't consistent with my own view of the serching process which isn't deductive, but I am open for changing my mind whenever convincing evidence is at hand, like always.

  18. Aug 3, 2009 #17


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    a) humans do not have free will, or
    b) humans are not completely described by the known (either classical or quantum) physical laws.

    Personally, I vote for physical laws.
  19. Aug 3, 2009 #18


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    I don't quite see a clean connection between the question of free will of humans and the structure of physical law.

    My only opinions is that a human is just as much a physical system as is an atom. The difference is the complexity, there is no divine distinction anywhere.

    What does it even mean from the point of view of measurement, wether object A has "free will"?

    The only sensible interpretaiton I can come up with is that free refers to "not constrained by the knowledge of the observer". In that case, free will seems to be related to unpredictability of the outside, as in "freedom of action", or "unpredictable action".

    If that's not what's mean, then what does it mean?

    I think we need a measure, or interaction scheme, from which to infere with some degree of certainty that object A has free will or not, otherwise it seems to be mainly some philosophy of mind, rather than philosophy of science or physics.

  20. Aug 3, 2009 #19


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    By your definition, free will is not an objective property of an object, because it is defined by knowledge of some observer. Two observers may disagree on whether object A has or has not free will. But in my language, only an objective property is a property. For example, beauty of an object is not a property of an object. So, with your definition of free will, the free will does not exist, just as beauty does not exist.

    I know, you will say that not only beauty and free will are subjective, but that EVERYTHING is subjective. Well, as you know, I do not agree with such a radical attitude. Nevertheless, if I would accept that everything is subjective (which indeed might be the case), then, in my language, nothing exists (except me, which brings us to the Descartes "Cogito ergo sum", but that's not science any more).
  21. Aug 3, 2009 #20


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    Absurd, this is 100% backwards. Precisely because of what we know about these forces, the kind of SD you describe is RULED OUT. They don't conspire to support Bell test results.
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