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This is sort of drifting away from the original topic, but it's late and I'm procrastinating, so what the hell:
But saying that QM is incomplete is a lot different than saying "I think it's all actually deterministic under the hood". I wasn't questioning whether you think QM is correct (i.e. that it gives the correct answer), I was asking why it is that you think digging deeper will uncover some conspiracy to appear random.
Well, I didn't say all of that. I said that QM is incomplete, yes, but that doesn't necessarily mean that it's deterministic under the hood. It's just that, from a theory standpoint, it makes more sense to work with the assumption that it is and go from there, because if it isn't, then there's no point to the math to begin with.
In summary, what I'm saying is that there is a historical trend in QM that trying to make it deterministic ends in failure. What I'm asking is: why do you believe, despite all the honestly incredible past criticisms that have been shot down, that it's really deterministic under the hood?
The short answer is that the math seems to point in that direction. The long answer is several papers long, and beyond the scope of the thread atm, but I can do a reader's digest version.
The "historical trend" as you put, (which, btw, is rather well stated), is there for a reason. It's not that we physicists are uncomfortable with the idea of QM, but there's a bit of it missing that can be well explained by some formalism of the measurement problem that involves determined (though not exactly predictable) outcomes. That missing bit can also be explained by throwing your hands in the air and going "Welp it's random", but that has a host of mathematical issues associated with it as well. It's a developing field, sort of.
There's also a host of other gedankenexperiments that can't be solved in the same way the EPR paradox is "solved" (there's some contention there as well, but that's beyond this particular point, and it's not significant to begin with) that a solid measurement theory would solve. A solid measurement theory (one that gives a quantitative description, and not a qualitative one like we have now) would also imply a deterministic mechanism, though it doesn't demand it.
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The math doesn't point in any direction. We see some problems like high energy divergence, but there is no argument that leads to determinism. (that I know of.) The main point is, that "the math" points in no direction, which is why the theories have gone wild and stuff like superstrings have erupted: We are lacking data, not theories.
And statements like
A solid measurement theory would also imply a deterministic mechanism, though it doesn't demand it.
are really far stretching.
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On March 31 2014 16:46 DefMatrixUltra wrote:
Their brain state can be affected by the environment and by the actions of others around them (who also have their own brain states) and, of course, by the previous brain states they held (their past, their memories, their experiences etc.).
this is a post from the future, your causal brain-state was a lie!
but well put, i was subscribed to this way of thinking myself.
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On March 31 2014 20:38 Hryul wrote:The math doesn't point in any direction. We see some problems like high energy divergence, but there is no argument that leads to determinism. (that I know of.) The main point is, that "the math" points in no direction, which is why the theories have gone wild and stuff like superstrings have erupted: We are lacking data, not theories. And statements like Show nested quote +A solid measurement theory would also imply a deterministic mechanism, though it doesn't demand it. are really far stretching.
In terms of what my view on the matter is, this is pretty much it. There isn't anything (that I am aware of) explicit or implicit in QM that says the stuff we currently don't know about QM is more of the same or something entirely different. The conceptual and arguably foundational issues with it generally border on the metaphysical and thus are hard to attack. QM is a functional theory, a workable theory, but it's not a theory that gives us a view or perspective of what you might call "objective reality". It just says, if you have situation A then B,C,D can result with probabilities E,F,G. The outcome of all tests in QM is well-established, but the theory says little of the mechanism through which that outcome is accomplished - and that's sort of the basic one-sentence summary of the functionality and "problem" with QM so far (to the best of my current knowledge). QM works incredibly well, so pragmatic people have no real issue with it whatsoever - but those seeking context have little to work with.
As far as opinions go, I know I'm not well-versed enough in the subject to have an opinion that matters. However, that won't stop me. I feel that if there is a deterministic mechanism underlying QM, then all sorts of paradoxes are opened up - some more subtle than others. For instance, if the entangled pair in the EPR paradox can be deterministically influenced, then that could (depending on the mechanism of influence) result in the possibility of faster-than-light communication - a paradoxical area that has been explored by others in great detail. The existence of things like faster-than-light communication are signs (to me) that a theory has strayed too far or does not put enough boundaries in place. It appears to me, then, that those who are trying to demonstrate determinism hiding under QM have a much more difficult job than the already extremely difficult job they apparently have. I think I'm metaphysically more OK with randomness as a basic mechanic of the universe than things like FTL communication - but, again, that has no real impact on whether one thing or the other is actually correct, it's just my feeling on the matter.
I know this isn't directly related to the OP, but I believe that it's more closely related to the concepts being grappled there than is apparent on the surface.
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On March 31 2014 05:54 DefMatrixUltra wrote:Show nested quote +On March 31 2014 04:46 hoby2000 wrote:On March 31 2014 04:40 neptunusfisk wrote:On March 31 2014 04:35 hoby2000 wrote:On March 31 2014 04:33 neptunusfisk wrote:
No, physicist discovered around the year 1900 that our universe is not deterministic at the smallest scales.
Where a particle wave is or where it is headed is not absolute and you can never predict things with the "perfect" precision of classical Newtonian physics.
See Heisenberg uncertainty principle or any introduction to (modern) physics for more details. You missed the point. It was not to discuss whether or not we could replicate the exact Bing Bang, but instead that we were under the assumption that we could already, and what that meant from the philosophical point of view. It has nothing to do with the actual science of the matter (nehe). I'm talking EXACTLY so that everything would be the same, which as you have even suggested, is no impossible. It's not likely, and having the ability to replicate something like that exactly would require a lot of control over physics - BUT AGAIN, the discussion wasn't if it was possible to do so, but the assumption that we already could. Even if you rewinded things a few seconds and then watched, and repeated several times, another thing would happen each time. Things aren't totally predetermined. A lot of it is governed by probabilities. Here's something "philosophical" for you: There is a non-zero possibility for the entirety of you to instantly tunnel your way through the floor, or to the moon for that matter. I know what you're saying, and I'm saying you still don't understand the premise of the argument. We're talking about complete control. I'm talking about exacltly what you're saying we don't have control over - we have control over. It's a philosophical thought experiment about the idea of free choice. Scientifically, yes, you're right, it's likely never going to happen, but the point is to consider choice. It's not to consider whether or not physics allows it to happen. The separation of particles is just a metaphor, it's not suppose to be completely literal. You're saying it's the thought experiment of "suppose we had total ability to set the big bang and the formation of the universe etc. in motion however we liked" that is of interest here. What would the moral upshot be? What would the philosophical upshot be? etc. You focus a lot (although it's hard to tell because you spend an awful lot of your post talking about things which you claim are ancillary) on what these concepts would mean about the kind of choices people make - what do our choices really mean? etc. This is having your cake and eating it too, though. At the very least it's quite unfair (if not paradoxical/nonsensical) to talk about the philosophical implications on choice of actors acting on a deterministic universe. I think we can all politely agree that a deterministic universe leaves no room for free will whatsoever. If the actors are acting on it as part of a thought experiment, that action in itself and its outcome are both predetermined. I feel this was glossed over, and I think that's what neptunusfisk was getting at. Even in a non-deterministic universe, there's perhaps not even theoretically a way that free will could exist. It might even be a nonsensical concept like a five-sided triangle or a square circle. Glossing over the concept that free will probably cannot even exist when talking about the impact and meaning of "choices" we make isn't really fair game imo, especially given the metaphors you used.
Before I begin, your reply is amazing. I'm sorry I haven't gotten around to replying to you yet, because you have asked some awesome questions. Thank you for reading what I've written by the way.
My retort:
The point you've made is valid, and I understand where you're coming from. I proposed an idea that suggested we had the ability to make a universe, then claimed how despite the fact we are able to re-create such circumstances, how could someone who is able to choose the beginning of such a thing be part of the limitation of free will implied by the circumstances of the thing they're creating? Wouldn't that mean that a deity would play under the same rules, therefore removing them from deity status? Does the creator not stay creator, and the actor stay actor?
My answer to this is that I didn't mean to imply that we were also the initial creators of the experiment, nor are we running it. I should have said that perhaps there was this ability to do so by a force that we cannot explain, be it deity or what have you, which can reproduce the world exactly, or even if it were to happen by accident the same way. The idea of the thought experiment was to suggest the possibility of a universe that would unfold exactly our own, and what that may imply philosophically.
The answer to your other question is that I honestly cannot argue with the fact I have jumped all over the place. My thought process works like this, and I unfortunately cannot get every piece out together at once. I barely get pieces that connect, so I understand when you say that I haven't actually answered the question yet because I haven't. The truth is that it will remain unanswered because I have to consider many options when considering the subject. I may have accidentally promised an answer, but I cannot give anyone the answer. I can only write my own and hope others take something good away from it. Incoherent ramblings to one man may be a few slices of genius to another. Many times have I noted things people have said and considered it deeper than they intended. This is the part about thought that I love because it shows the chaotic part of existence that I want to write about more in the future.
I have to write more, and hope that people start to understand my thoughts. I attempt to organize on my side, and posts like yours are wake up calls that I am becoming lazy when it comes to organizing thoughts together. I cannot promise more organization, but I will make an attempt. I may even write more organized if I like how it turns out, but again, that's how life works. General metaphors and one-line sentences that go unexplained but can be translated into an idea that could inspire the next Einstein, or Socrates, or Newton, or Hayek, or The Beatles, or Jaedong, etc. That being said, I would like to be able to convey my idea of free will better, but again I will be writing more about it in the future to attempt to further explain the ideas I've presented here, in the future, and in the past.
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On March 31 2014 17:51 NuclearVII wrote:This is sort of drifting away from the original topic, but it's late and I'm procrastinating, so what the hell: Show nested quote +But saying that QM is incomplete is a lot different than saying "I think it's all actually deterministic under the hood". I wasn't questioning whether you think QM is correct (i.e. that it gives the correct answer), I was asking why it is that you think digging deeper will uncover some conspiracy to appear random. Well, I didn't say all of that. I said that QM is incomplete, yes, but that doesn't necessarily mean that it's deterministic under the hood. It's just that, from a theory standpoint, it makes more sense to work with the assumption that it is and go from there, because if it isn't, then there's no point to the math to begin with. Show nested quote + In summary, what I'm saying is that there is a historical trend in QM that trying to make it deterministic ends in failure. What I'm asking is: why do you believe, despite all the honestly incredible past criticisms that have been shot down, that it's really deterministic under the hood? The short answer is that the math seems to point in that direction. The long answer is several papers long, and beyond the scope of the thread atm, but I can do a reader's digest version. The "historical trend" as you put, (which, btw, is rather well stated), is there for a reason. It's not that we physicists are uncomfortable with the idea of QM, but there's a bit of it missing that can be well explained by some formalism of the measurement problem that involves determined (though not exactly predictable) outcomes. That missing bit can also be explained by throwing your hands in the air and going "Welp it's random", but that has a host of mathematical issues associated with it as well. It's a developing field, sort of. There's also a host of other gedankenexperiments that can't be solved in the same way the EPR paradox is "solved" (there's some contention there as well, but that's beyond this particular point, and it's not significant to begin with) that a solid measurement theory would solve. A solid measurement theory (one that gives a quantitative description, and not a qualitative one like we have now) would also imply a deterministic mechanism, though it doesn't demand it.
I'm going to read the rest of your post, but drifting away from the original topic is good. Please continue to tangent as you please so you may inspire others to do the same, and pop-up some thoughts you may not have known you had.
Also, before continuing to read, thank you all for replying even if you're not directly replying to my original post.
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On March 31 2014 16:46 DefMatrixUltra wrote:There are certainly limitations on our knowledge of physics (thus, the incompleteness of QM). But saying that QM is incomplete is a lot different than saying "I think it's all actually deterministic under the hood". I wasn't questioning whether you think QM is correct (i.e. that it gives the correct answer), I was asking why it is that you think digging deeper will uncover some conspiracy to appear random. Saying "we don't know either way" is a cop-out. Depending on how stringently you define "know" we can't really "know" anything ever, we can't really "prove" anything ever, we can only increase probability that something is correct. Saying that it seems like it might be random is (if you'll forgive the rudeness of the metaphor) akin to saying that the sun seems like it might be hot instead of cold. Sure, it could certainly be the case that it's cold (anything that's not literally impossible is possible), and it might even make an interesting area of thought, but all the indications are that it's hot - many arguments have been brought forward about its hotness, and all those arguments have ended up adding to the probability that it's hot. The arguments I was referring to were not all arguments pertaining to QM ever - it was specifically those that sought to undo or modify the theory by introducing determinism or having determinism as a basic assumption. So far, all those arguments (e.g. the EPR paradox) have not met with any success and have served only to indicate more strongly that things in QM like wave collapse are some kind of basic mechanic for which there is no underlying mechanism (at least, not a deterministic one). The fact that QM and GR don't fit nicely together does not indicate to me in any way that QM is floating above some deterministic theory. It's likely more of a reflection of our inability to fully uncover the scope of the theories, especially considering it's not exactly easy to perform experiments with some concepts of GR. In summary, what I'm saying is that there is a historical trend in QM that trying to make it deterministic ends in failure. What I'm asking is: why do you believe, despite all the honestly incredible past criticisms that have been shot down, that it's really deterministic under the hood? /edit - A bit closer to the original topic: Show nested quote +On March 31 2014 07:31 neptunusfisk wrote:On March 31 2014 05:54 DefMatrixUltra wrote:
Even in a non-deterministic universe, there's perhaps not even theoretically a way that free will could exist. It might even be a nonsensical concept like a five-sided triangle or a square circle. Glossing over the concept that free will probably cannot even exist when talking about the impact and meaning of "choices" we make isn't really fair game imo, especially given the metaphors you used. This is very vague. An abstract concept like "will" or "conciousness" is just a construction playing with the old belief of body and soul duality. People do things in reaction to their surroundings because they feel like it. These urges, albeit primitive could be recognized as an expression of will. Or not. It's just not well defined what OP is aiming for. I think we can safely and politely do away with talking about "souls" etc. for the purpose of this discussion. A person's personality or "essence" is defined by their brain state. Their brain state can be affected by the environment and by the actions of others around them (who also have their own brain states) and, of course, by the previous brain states they held (their past, their memories, their experiences etc.). It's pretty much a given that the universe runs on some kind of physics, some set of rules that, were we intelligent and capable enough, we could fully define and catalogue. The environment runs purely on these physics. Our brains also run purely on these physics. In fact, there is quite literally no influence on our brain states that isn't a physics-based influence. Where is there room for free will? Our brain states are in the the states they are in. Our brains react to stimulus as they do. Even when we make a decision, we are consulting our brain state in order to form an internal logic. It seems clear that we will act and decide according to our internal logic. Where is the mechanism for free will? We are enslaved to do whatever our physics-driven brains decide we will do. Unless there's some missing mechanism, there is simply no room for free will.
I'm going to need to mull over this for a bit. You make some good points and honestly, I cannot write a reply I think is good enough now that I've read all your posts. But a fantastic read, by the way. I'll have a reply eventually, but I'm going to need to think this through for a bit. Well done sir, well done.
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Shoutout to DefMatrixUltra. Very sensible replies between all physics students...
More ontopic, i don't really understand a part of the line of reasoning. your friend said something like the big bang being reproducable, and we would end up the same way every time it was reproduced. Is there a reason why we would assume that would be the case? As far as i know, there isnt really a reason to assume/conclude that. How would we test such a thing? If we were to acknowledge that the universe would not necessarily play out the same way, it's either irrelevant to the discussion on free will, or we wouldn't be certain in any way about the connection between free will and the evolution of the universe as a whole. In both cases, there isn't really a discussion.
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All physics students should check out classical the Bell's inequation which rules out any local hidden parameters theories and further developments of the Quantum Measures theory, which elaborate that even if hidden nonlocal parametres exist, they don't bring add any additional information before/after the measurement. When scientists say QM is incomplete, they mean that the classic theory couldn't be built without the assumption of the laws of Classical Mechanics, which shouldn't be the case of self-consistent and more general theory. As far as I know, the phemenology of quantization using Feymnan's funcitonal integrals partly solves this problem, but it substitutes it with another, a mathematical, one: Classical Quantum Mechanics theory was proved to be not only physically, but mathematically correct by John von-Neumann before it's wide international recognition, and there isn't any recipe for doing that with Feynman's integrals at the horison yet, because infinite measures (mathematic term) aren't well-defined for all kinds of functional spaces quantum theoretic physicists work with.
TLDR: New century needs new mathematics to complete and expand the already working theories (superstrings, anyone?).
@hoby2000, applying QM's laws and prospects to the neuron's systems in one's brains is generally considered as un-scientific approach, but I think your friend is right: free will doesn't exist in a way. When your brain makes decisions it's restricted not only by all sorts of internal and external conditions, but by the very history of mankind itself due to it's heuristic mechanism: if some actions brought you success in past, you're bound to try them in future. As for, whether the world be the same if we "restart" it from the get go, generally speaking, the satisfactory answer is "yes", but only on a large space-time scales (centuries or thousands years, at least). The details are ought to be different due to undeterministic way of nature itself.
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EPT
