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Do Subatomic Particles Have Free Will?

Posted by kdawson on from the painting-fences-white-very-quickly dept.

An anonymous reader sends in a Science News article that begins: "Human free will might seem like the squishiest of philosophical subjects, way beyond the realm of mathematical demonstration. But two highly regarded Princeton mathematicians, John Conway and Simon Kochen, claim to have proven that if humans have even the tiniest amount of free will, then atoms themselves must also behave unpredictably." Standard interpretations of quantum mechanics, of course, embrace unpredictability. But many physicists aren't comfortable with that, and are working to develop deterministic interpretations of quantum mechanics. Conway and Kochen's proof argues that these efforts will be fruitless — unless one is willing to give up human free will, in a very strong sense. The article quotes Conway: "We can really prove that there's no algorithm, no way that the particle can give an answer that is unique and can be specified ahead of time. I'm still amazed that we can actually manage to prove that."

16 of 608 comments (clear)

  1. How about a link to the actual article? by Anonymous Coward · · Score: 5, Informative

    http://arxiv.org/abs/0807.3286

  2. Re:Uh, what? by Anonymous Coward · · Score: 5, Informative

    There's already considerable evidence that humans don't have free will, but that free will is (essentially) an illusion created by your brain.

    So, no, particles do not have free will.

    Let A be "Humans have free will." and let B be "Subatomic particles have free will.". Conway and Kochen says A->B. You assume ~A and draw the conclusion ~B. That's not justified. I'm sure there is a Wikipedia entry on this logical fallacy.

  3. Free Will != Unpredictability by MaxEmerika · · Score: 5, Interesting

    Unpredictability has nothing to do with free will. I can be completely predictable and still be acting freely. Conversely, if my actions are random, how can I be said to have any control over them?

    1. Re:Free Will != Unpredictability by nasor · · Score: 5, Informative

      Generally when people talk about "free will" in this sort of sense they mean that if you must choose between A or B, before you make your choice there is some non-zero possibility that you could pick either A or B. If your choice is governed by the mechanisms of a deterministic universe, there is really no possibility that you could pick either one; your choice is predetermined, and an observer with enough information could calculate with certainty what your choice will be before you make it. If you want to say that being free is simply being unconstrained to do what you try to do, then a robot following a program is "free," so long as nothing interferes with it trying to do what it is programmed to do.

  4. Wide Interpretation of Freewill is at fault by topham · · Score: 5, Insightful

    Think about a definition of Free Will for a while. Then answer this question:

    If an exact copy of you were made (absolutely exact, right down to the quantum state of every particle); do you believe that given the exact same environment (a twinned universe?) your doppleganger would ever do anything different than yourself?

    If you believe that you would not act, and think exactly the same then you believe Free Will is beyond quantum mechanics; otherwise Free Will is just the synergistic response to a complex organism that has the capability to think of itself.

    1. Re:Wide Interpretation of Freewill is at fault by esmoothie · · Score: 5, Informative

      If you believe that you would not act, and think exactly the same then you believe Free Will is beyond quantum mechanics; otherwise Free Will is just the synergistic response to a complex organism that has the capability to think of itself.

      Actually, no. Ignoring the no cloning theorem for a moment, if two particles are in the exact same quantum state, then they can collapse to two different values. This is precisely the indeterminacy of quantum mechanics.

    2. Re:Wide Interpretation of Freewill is at fault by LeafOnTheWind · · Score: 5, Insightful

      Mod parent up. Finally someone who knows what they are talking about.

      The buzzword "free will" is bringing out the idiots with no science education. This discussion simplifies to one thing - if, given all the requisite variables in a system, one can predict the next infinite states of that system, that system is deterministic. Id est, if, ignoring the cloning theorem and other QM restraints, one knew the exact state of every particle in the human body and one could predict the next infinite states of that system (the body), then that system would be deterministic (have no "free will"). If, on the other hand, the human body (more precisely, the mind) could be proven to have a finite number of predictable states, then the underlying physical systems must therefore also have a finite number of predictable states (be unpredictable).

      Now, QM predicts that subatomic particles are unpredictable. Technically, that would make our minds unpredictable HOWEVER - unpredictable is defined precisely as being unable to predict an infinite number of states in the system. A finite (even large) number may still be possible. This would the generalization of a large number of unpredictable subsystems in the system used to approximate the future states. As we see with Newtonian physics, this method can be fairly accurate.

      The only way that humans could be proven to be completely predictable would be to disprove the tenets of quantum mechanics. Until then, humans have "free will."

  5. Re:Uh, what? by Anonymous Coward · · Score: 5, Informative

    And for those who haven't studied that notation... "A->B" is "A implies B" (if A, then B)... "~A" is "not A". "A->B" is the same as "~A V B" ((not A) or B)

  6. No: Free will + statistics by Roger+W+Moore · · Score: 5, Insightful

    No - in Asimov's world humans can have free will in exactly the same manner as quantum mechanical particles can have "free will" and yet Newtonian mechanics (which is deterministic) can accurately describe the physics of things a lot larger than an atom. There is a probability for each human/particle to make different choices and, when statistically sampled on a large enough scale, those probabilities lead to something that appear deterministic.

    This is exactly how quantum mechanics work. Each particle has a probability distribution for what it will do so that, at the large scale because of the huge numbers involved we know that roughly 40% will do X, 20% will do Y and 40% will do Z.

    While I don't know for certain that Asimov based psycho-history on QM I've often suspected as much. As a PhD chemist he should have had a reasonably good understanding of QM at least.

    1. Re:No: Free will + statistics by Anonymous Coward · · Score: 5, Interesting

      The "average behavior of crowds is deterministic" thing doesn't really work. The sum or average of a set of random variables is also a random variable.

      There is a well known result in probability theory called the central limit theorem that says that if you add up enough independent, identically-distributed random variables together you get a normal distribution (i.e. bell curve). Lots of people try to apply this to economics (or in Asimov's case, history), but it doesn't work in practice. Individual actions are not independent or identically distributed. People's actions are correlated to other people's actions. Some people have vastly more influence on the aggregate outcome than others.

      So the central limit theorem can't be applied to aggregate behavior. Instead of getting a nice well behaved normal distribution, you'll end up with a distribution that's messy, unpredictable, and confusing, which is fitting, since that's what we humans are.

  7. Re:Uh, what? by Kagura · · Score: 5, Insightful

    You mean the extremely complex deterministic chemical reactions in your brain will ignore his future posts, not your free will.

  8. Re:Uh, what? by jabithew · · Score: 5, Informative

    This is the fallacy you refer to.

    Wikipedia is very, very good on mathematics and logic.

    --
    All intents and purposes. Not intensive purposes.
  9. Re:Uh, what? by XcepticZP · · Score: 5, Insightful

    Exactly. We, people, want to believe that we are all unique. This dates back to when philosophers starting separating humans from everything else, which they dubbed "mindless automatons". We humans are supposed to have a "soul". Determinism takes all that away from us and simply tells us that we really are not separate from the environment, because we're made of the same things. Free will was spawned by the same thing that spawned religion.

  10. Re:Uh, what? by lgw · · Score: 5, Interesting

    I believe that we have free will, *and* that the universe is completely deterministic. The two concepts are orthgonal. One cannot have "illusion of free will" any more than one can have "illusion of pain". If I believe that I'm in pain, than I necessarily am in pain, even if the pain comes from e.g. a limb that no longer exists - doesn't matter: if it hurts, it hurts.

    Similarly, if I consciously decide my next actions, then I necessarily have free will, regardless of whether the universe is pre-determined. You might argue that in a deterministic universe all consciousness is an illusion - but that's an unreawrding path to travel.

    In any case, arguing "if I have free will, then the universe is not deterministic" is not logical - the assumption that "determinism is incompatible with free will" has been argued by philosophers for centuries, without conclusion. Feel free to believe that - many do - but don't state it as a fact.

    --
    Socialism: a lie told by totalitarians and believed by fools.
  11. Re:Uh, what? by h4rm0ny · · Score: 5, Funny


    Well that's their choice.

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    Aide-toi, le Ciel t'aidera - Jeanne D'Arc.
  12. Re:Uh, what? by moosesocks · · Score: 5, Funny

    This is the fallacy you refer to.

    Wikipedia is very, very good on mathematics and logic.

    Just hold on a sec......

    There.

    Now it isn't. The mathematics & logic portion of wikipedia is now, however, a very very good authority on Rick Astley's greatest hits.

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    -- If you try to fail and succeed, which have you done? - Uli's moose