As the final section shows, this is more about the question of determinism vs indeterminism. Depending on your particular ontological and epistemological leanings, that question and the question of free will may be the same, or conflating the two may be a category error. I personally fall in the latter camp, but this was an interesting foray into the musings of a brilliant mind.
Indeed - and one can eliminate determinism without resort to QM: Classical mechanics is also indeterministic, you just have to know where to look.
Read "Causation as Folk Science" by John D. Norton [1]. He sets out a very simple example of a classical system that behaves indeterministically, analogous if not in fact homologous to how the radioactive decay of a single particle cannot be predicted.
The apparatus to demonstrate this consists of a dome with a particular curve (see the paper for details). A sphere placed at the apex of the dome will eventually roll off, in a random direction. But we can predict NEITHER when NOR which direction. And yet it is a fully defined classical system.
(And see [2], recently discussed here, to see how relevant and frutiful classical mechanics remains to this day.)
(Note that a better word than indeterministic might be acausal, which is the word Norton uses when describing the dome. Either way, one need not resort to QM, regardless interpretation, to demonstrate that determinism does not in fact prevail in our universe. We can all behave in ways that are not predetermined.)
Whenever I face the arguments of determinism vs. indeterminism, I wonder how indeterminism would be defined in a purely indeterministic world. I don't know. But in this seemingly deterministic universe, we define indeterminism as a negative sense to the deterministic dynamics we observe, but we can't do it in a positive sense. All of our conceptions of "indeterminism" and random/chaos like concepts is all "determinism-biased" in that sense. Maybe, determinism might be a tiny, tiny small subset of a huge set of indeterminism, as if integers are a tiny subset of all real numbers. There's no such a thing as integers vs. real numbers. Integers are also just real numbers. In that sense, determinism might be a small part of indeterminism.
So you're saying the world can be deterministic and you can still have free will? That would mean you would have to believe in something like souls then, right? Something outside of this physical world that influences your physical existence? I'm not questioning your views just trying to understand.
Conway's description of entanglement is misleading. FIN does not actually apply here. According to quantum physics, no information is exchanged between the particles. If information is exchanged, it is not limited to any finite speed we know of.
The thought experiment he describes is well-known in the popular science press: you create two particles with opposite spins (angular momenta), but such that the spins are not determined. As soon as you measure the spin of one the spin of the other becomes determined -- INSTANTLY. There is no speed-of-light limit here. If you describe the situation as two particles colluding by sharing some "information," then FIN does not apply, as far as we know! (And if there is a limit, it is greater than the speed of light.) A physicist would instead say that no actual information is transmitted, and entanglement cannot be used to transmit information faster than the speed of light.
Since the metaphor of wave function collapse as information sharing between particles leads to incorrect physics, I don't think we should read too much into the metaphor of measurements as "free choices" of a particle.
I'm surprised that people are so determined (heh) to pull determinism out of quantum mechanics. I don't believe in metaphysical souls or free will per se, but I also accept randomness in quantum mechanics (relational interpretation).
I have a very limited understanding of physics but two questions spring to mind:
1) Why is there little doubt in the axioms, especially FIN? It requires the concepts of distance and time, either of which might not be applicable to the resulting property.
2) Why call the resulting property "free will" or "free whim"? As far as I can tell the proof is for the existence of an additional property to both the experimenter and the particle, but there is no real description of it. This is somewhat unsatisfactory addressed in the last paragraph, but really, why not just call it a "randomness" or "god" instead of "whim"?
1. Current physics - and in a way it goes back to Descartes and the very first conception of modern physics, the idea that things happened for mechanistic reasons rather than mysterious temperaments. If information can travel instantaneously, doesn't that imply that distance and time are in some sense meaningless? Also, relativity + faster-than-light information implies causality violation, grandfather paradox and all of that. It's not "beyond all reasonable doubt", but standard physics seems to respect it as an axiom.
If FIN were false it would be possible to transmit information backwards in time by transmitting it faster than light between a transmitter and receiver moving relative to one another.
If I understand this correctly, this proof is used to exclude one of the two given explanations for the "Kochen-Specker Paradox"?
The article says the KS "paradox" implies that either
> 1. Each measurement of a particle is not independent but rather depended on
> context. In other words, the order in which you make measurements matters.
or
> 2. The particle does not decide what the value of its spin is in any direction
> until the experimenter actually makes a measurement!
As I understand it, the proof shows that the order in which you take the measurements can't matter, excluding explanation (1), because of the following thought experiment.
* Take two particles, entangled and then separated by some distance.
* More quickly than information can pass between the particles, measure one particle in three directions in some order, and measure the other particle just once in one direction which you choose right at that moment.
The second particle can't be affected by the order in which you measured the first particle's spins, but if I was able to choose a direction in which to measure the second particle's spin, then the second particle was able to choose a result to match the appropriate result from the first particle's measurements.
I think I followed this argument up until the last sentence above. What I (mis)understand to be happening here is "spooky action at a distance"; it doesn't at all appear to be a free choice on the particle's part.
In essence we established via the KS paradox that our two particles couldn't have "agreed" on their spins ahead of time, because there's no consistent way to assign all of their spins. But then we measured the two particles in the proscribed way and got a result that looks like the particles did agree on their spins beforehand.
I believe that this excludes explanation (1) from above, but I don't understand how explanation (2) is consistent with this. If it were the case that the particle was deciding its spin at measurement time (explanation (2)), wouldn't the two particles have to communicate faster than c (or whatever our speed limit is) in order to ensure that they made the same decision? We explicitly ruled out this possibility via the FIN axiom and our experimental setup.
The only way I can think of to make this work is to say that the universe doesn't "choose" which result I got until I meet up with my friend who measured the other particle. But this seems to be a far stronger claim than the article makes.
Talk about the particle "deciding" is coming from a Copenhagen interpretation viewpoint. I find the many-worlds view clearer:
When the two particles are set up, their wavefunctions are in sync (or rather, antisync) with each other. Particle A's wavefunction looks like an equal superposition of up and down (at least, when projected onto a single axis; the wavefunction for the full particle incorporating all the possible axes is more complicated); Particle B's wavefunction is the same but 180 degrees out of phase, so that A is up whenever B is down and vice versa.
When you make a measurement of particle A, you entangle yourself with it; that is, your own wavefunction becomes in phase with its. (Again, it's still an equal superposition between having measured up and having measured down). When your friend makes their measurement of particle B, they entangle themselves with it in the same way. So when you meet up with your friend, your wavefunctions are in (anti)phase; the universe as a whole is an equal superposition of the world where you measured up and your friend measured down, and the world where you measured down and your friend measured up.
(What does being in that superposition look like, subjectively? It looks like a 50% probability of the first world and a 50% probability of the second world. Which agrees with what we measure when performing the experiment)
I don't know about all that quantum math craziness or that spin fin twin nonsense but it sounds like Conway shares a long standing sentiment I've had that "free will" is a story we tell ourselves because we want to believe our choices are based on something fundamentally more complex or important than the choices of an animal or a computer. Even if "free will" is a real thing and not just an illusion, what is it really but random in-deterministic variations, or what Conway called whims.
I remember when I voiced these opinions in my college philosophy class to a room full of denialists. It's good to know I'm not alone in my thinking in a world where multi-verse and string theory are sooner accepted than the fact that free will is an illusion.
'A world where multi-verse and string theory are sooner accepted ...' indicates a world where there is agency, and thus will. We won't even go near your normative subjective ideas about the 'good'.
You can't both deny the existence of free will, and castigate those whom with you disagree. If you're right, then none of us can be wrong -- certainly no more than a plant or a rock or the moon can be wrong.
The first diagram of the proof starts with "there exists some experimenter with at least some free will". That's a problem, as it uses the argument's conclusion as one of its premises.
Using a simpler example, it'd be like saying, "To prove that aliens exist, let me show you three simple steps: 1) let's assume aliens exist, 2) ...
The second problem here is that he seems to be trying to illustrate that if things cannot be predicted that we have free will. This is a common fallacy in the free will debate. Randomness is an attack on fatalism, but offers ZERO degree of control to humans, and therefore has no place in the free will debate.
Finally, if you want to see a much better argument, in the other direction, check out my Two Lever Argument Against Free Will that uses 25 lines of Ruby.
> it uses the argument's conclusion as one of its premises.
His theorem doesn't assert free will. It asserts that if experimenters have free will, then particles have free will. So if it's wrong, then it's not for the reason you give.
Isn't the conclusion, "all particles have free will"? So, the arguments conclusion is pretty far from its premise. "All numbers are larger than 5" is very far from "some number is larger than 5".
And, whether or not you call this property "free will" is irrelevant to the proof itself; see the final paragraph.
[+] [-] eseehausen|11 years ago|reply
[+] [-] PeterWhittaker|11 years ago|reply
Read "Causation as Folk Science" by John D. Norton [1]. He sets out a very simple example of a classical system that behaves indeterministically, analogous if not in fact homologous to how the radioactive decay of a single particle cannot be predicted.
The apparatus to demonstrate this consists of a dome with a particular curve (see the paper for details). A sphere placed at the apex of the dome will eventually roll off, in a random direction. But we can predict NEITHER when NOR which direction. And yet it is a fully defined classical system.
(And see [2], recently discussed here, to see how relevant and frutiful classical mechanics remains to this day.)
(Note that a better word than indeterministic might be acausal, which is the word Norton uses when describing the dome. Either way, one need not resort to QM, regardless interpretation, to demonstrate that determinism does not in fact prevail in our universe. We can all behave in ways that are not predetermined.)
[1] http://www.pitt.edu/~jdnorton/papers/003004.pdf
[2] http://arstechnica.com/science/2014/08/the-never-ending-conu...
[+] [-] protez|11 years ago|reply
[+] [-] tacotime|11 years ago|reply
[+] [-] dgreensp|11 years ago|reply
The thought experiment he describes is well-known in the popular science press: you create two particles with opposite spins (angular momenta), but such that the spins are not determined. As soon as you measure the spin of one the spin of the other becomes determined -- INSTANTLY. There is no speed-of-light limit here. If you describe the situation as two particles colluding by sharing some "information," then FIN does not apply, as far as we know! (And if there is a limit, it is greater than the speed of light.) A physicist would instead say that no actual information is transmitted, and entanglement cannot be used to transmit information faster than the speed of light.
Since the metaphor of wave function collapse as information sharing between particles leads to incorrect physics, I don't think we should read too much into the metaphor of measurements as "free choices" of a particle.
[+] [-] scythe|11 years ago|reply
[+] [-] starmole|11 years ago|reply
I have a very limited understanding of physics but two questions spring to mind:
1) Why is there little doubt in the axioms, especially FIN? It requires the concepts of distance and time, either of which might not be applicable to the resulting property.
2) Why call the resulting property "free will" or "free whim"? As far as I can tell the proof is for the existence of an additional property to both the experimenter and the particle, but there is no real description of it. This is somewhat unsatisfactory addressed in the last paragraph, but really, why not just call it a "randomness" or "god" instead of "whim"?
[+] [-] lmm|11 years ago|reply
2. Because Conway likes attention.
[+] [-] lisper|11 years ago|reply
[+] [-] jamesaguilar|11 years ago|reply
[+] [-] jamesaguilar|11 years ago|reply
[deleted]
[+] [-] jlebar|11 years ago|reply
The article says the KS "paradox" implies that either
> 1. Each measurement of a particle is not independent but rather depended on > context. In other words, the order in which you make measurements matters.
or
> 2. The particle does not decide what the value of its spin is in any direction > until the experimenter actually makes a measurement!
As I understand it, the proof shows that the order in which you take the measurements can't matter, excluding explanation (1), because of the following thought experiment.
* Take two particles, entangled and then separated by some distance.
* More quickly than information can pass between the particles, measure one particle in three directions in some order, and measure the other particle just once in one direction which you choose right at that moment.
The second particle can't be affected by the order in which you measured the first particle's spins, but if I was able to choose a direction in which to measure the second particle's spin, then the second particle was able to choose a result to match the appropriate result from the first particle's measurements.
I think I followed this argument up until the last sentence above. What I (mis)understand to be happening here is "spooky action at a distance"; it doesn't at all appear to be a free choice on the particle's part.
In essence we established via the KS paradox that our two particles couldn't have "agreed" on their spins ahead of time, because there's no consistent way to assign all of their spins. But then we measured the two particles in the proscribed way and got a result that looks like the particles did agree on their spins beforehand.
I believe that this excludes explanation (1) from above, but I don't understand how explanation (2) is consistent with this. If it were the case that the particle was deciding its spin at measurement time (explanation (2)), wouldn't the two particles have to communicate faster than c (or whatever our speed limit is) in order to ensure that they made the same decision? We explicitly ruled out this possibility via the FIN axiom and our experimental setup.
The only way I can think of to make this work is to say that the universe doesn't "choose" which result I got until I meet up with my friend who measured the other particle. But this seems to be a far stronger claim than the article makes.
What's the right way of thinking about this?
[+] [-] lmm|11 years ago|reply
When the two particles are set up, their wavefunctions are in sync (or rather, antisync) with each other. Particle A's wavefunction looks like an equal superposition of up and down (at least, when projected onto a single axis; the wavefunction for the full particle incorporating all the possible axes is more complicated); Particle B's wavefunction is the same but 180 degrees out of phase, so that A is up whenever B is down and vice versa.
When you make a measurement of particle A, you entangle yourself with it; that is, your own wavefunction becomes in phase with its. (Again, it's still an equal superposition between having measured up and having measured down). When your friend makes their measurement of particle B, they entangle themselves with it in the same way. So when you meet up with your friend, your wavefunctions are in (anti)phase; the universe as a whole is an equal superposition of the world where you measured up and your friend measured down, and the world where you measured down and your friend measured up.
(What does being in that superposition look like, subjectively? It looks like a 50% probability of the first world and a 50% probability of the second world. Which agrees with what we measure when performing the experiment)
[+] [-] tacotime|11 years ago|reply
I remember when I voiced these opinions in my college philosophy class to a room full of denialists. It's good to know I'm not alone in my thinking in a world where multi-verse and string theory are sooner accepted than the fact that free will is an illusion.
[+] [-] jamesaguilar|11 years ago|reply
[+] [-] JackFr|11 years ago|reply
'A world where multi-verse and string theory are sooner accepted ...' indicates a world where there is agency, and thus will. We won't even go near your normative subjective ideas about the 'good'.
You can't both deny the existence of free will, and castigate those whom with you disagree. If you're right, then none of us can be wrong -- certainly no more than a plant or a rock or the moon can be wrong.
[+] [-] danielrm26|11 years ago|reply
The first diagram of the proof starts with "there exists some experimenter with at least some free will". That's a problem, as it uses the argument's conclusion as one of its premises.
Using a simpler example, it'd be like saying, "To prove that aliens exist, let me show you three simple steps: 1) let's assume aliens exist, 2) ...
The second problem here is that he seems to be trying to illustrate that if things cannot be predicted that we have free will. This is a common fallacy in the free will debate. Randomness is an attack on fatalism, but offers ZERO degree of control to humans, and therefore has no place in the free will debate.
Finally, if you want to see a much better argument, in the other direction, check out my Two Lever Argument Against Free Will that uses 25 lines of Ruby.
http://danielmiessler.com/blog/two-lever-free-will-ruby/
[+] [-] pjungwir|11 years ago|reply
His theorem doesn't assert free will. It asserts that if experimenters have free will, then particles have free will. So if it's wrong, then it's not for the reason you give.
[+] [-] carstimon|11 years ago|reply
And, whether or not you call this property "free will" is irrelevant to the proof itself; see the final paragraph.
[+] [-] jamesrom|11 years ago|reply
[deleted]