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WARNING There is no science in this discussion. It's all philosophy. If you care to discuss whether or not scientific principles would permit the duplication of our universe, do so in another blog or thread. This is not about whether or not we CAN, but if we COULD, what that would mean, or even means to us right now.
I had a friend point out to me once that free-will is minimal at best. There are plenty of arguments that I've heard for this, but was curious to hear his reasoning. He suggested that if we were able to replicate The Big Bang as is, we would have the exact universe that we live in now, implying that who we are is simply a few things happening in the beginning, or the initial separation of particles. This was something that sort of caught me off guard as I had been set in stone about the idea of cooperative chaos where the world continues to work not because of any one point of motivation, but because of various motivations, some opposite each other, still working together to move society along. Taking what my friend had said into context, I realized that if the Big Bang were played out over and over, then we were simply living a life that had already been lived, or is being lived right now. Was choice really that irrelevant?
This whole idea had me on a philosophical thought train where I started thinking about the world at large, and how many choices I really had that I could make that weren't pre-planned. I knew that the foundations I had constructed recently were not going to crumble under this new thought, because I knew there was an answer to this whole mess, I simply couldn't word it correctly. Some tangent thoughts that happened because of this was the idea of time travel, and how if the Big Bang is being played out the same way in a different dimension, that maybe we should consider dimension traveling instead of attempting to travel through the time line we were already living. This would explain why we can't change the dimension around us, but how we may affect other dimensions playing out the exact same path. This would mean that our own dimension may have already been affected by those from other dimensions which could explain all sorts of things. Possibly one of my favorite tangent thoughts I've been on. Anyway, back to my answer...
I started thinking about the separation of particles, and how the start of the after effect of the big bang was near the top of the hierarchy of choices that were made leading to my own existence. What I realized was that though the initial separation was one at the top, I was still apart of the current separation of particles that continues to play it's part in the universe. Despite how little my choice is in comparison the weight of the choices leading to the creation of the solar system, it's still at the fore font of action that is changing the world around me.
The separation of particles is a never ending cycle of choices that continue to expand as time goes on.We may have had little to nothing (likely the latter) to do with any of our creations, and even our parents or their parents made smaller choices (but are larger than our own) in the grand scheme that led to us inhabiting the earth - But we are still a part of the little changes in the world that will be a bigger part in someone else's life later down the line. When we're all dead, living as spirits through pictures and texts, the choices we made will seem bigger to them because of the choices that were required leading up to them being able to know about it.
 
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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.
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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.
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On March 31 2014 04:35 hoby2000 wrote:Show nested quote +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.
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On March 31 2014 04:40 neptunusfisk wrote:Show nested quote +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.
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I don't understand what is interesting about it then, if the universe is deterministic like you want it to be, then yes everything will be always the same, i can't see what you expect to happen here 
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On March 31 2014 04:50 The_Red_Viper wrote:I don't understand what is interesting about it then, if the universe is deterministic like you want it to be, then yes everything will be always the same, i can't see what you expect to happen here
Because even though something will be different upon doing the experiment again, there may be a chance it might end up the same. It can't be different every time, but as far as we know, it is. That being said, considering the possibility of a parallel universe that could exist where everything plays out the same draws the conclusion that we have little to do with how we've come to be up to a certain moment, then it becomes our turn determine what happens from there. The thought experiment he provided sparked the idea of writing about The Separation of Particles as an example where free choice will always exist, and it does so chaotically. We exist through millions to billions of random choices, but that doesn't mean we don't have the ability to choose.
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On March 31 2014 04:46 hoby2000 wrote:Show nested quote +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.
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I am not sure i can follow your thoughts here.
I thought you imply that we start with the same "big bang" and everything that follows is 100% deterministic?
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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.
As a physics student I have to interject
I think you're being a bit too absolutist about what the theory actually says. All we have is a (phenomenally) successful model that operates on the principle that certain observables, like position or momentum, can only be determined in the form of an average (or expectation) value; or that the location of a quanton over all space is described by a normalized probability distribution.
But just because the model works well by viewing the distribution as being random, I don't think it necessarily means that the core mechanism by which an electron "chooses" to be in a certain state is literally random. There could easily be many hidden variables that operate on the wavefunction, which we are unaware of yet.
Just like if you imagine rolling a die; the interaction of the die with air molecules, the table, the momentum and spin imparted by your hand, can all combine to create something seemingly random. And of course, if we created a theory describing how the die lands, it would be very successful to describe it as a random process. Does this mean that the underlying mechanisms are random? I don't think we can infer that.
If you knew what all of these variables were, you could almost certainly predict how the die lands each time. I think science is far from saying anything about whether the universe is deterministic or random at its core. Of course there is also the uncertainty principle; but remember this doesn't say anything about whether a process is random or not. All it means is that we can't *measure* position and momentum both with exacting precision (below a certain threshold); it doesn't say or imply anything about what the underlying mechanisms are that make this determination impossible.
For example (as I learned), if you shorten a wave so that it only has one peak, it becomes impossible to measure the wavelength because you don't have enough information. But with one peak, you can clearly determine position. There is no randomness involved here; just a fundamental limitation of dealing with waves.
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Anyway to the OP: I'm not absolutely sure whether the universe is fundamentally deterministic or not. I like to think we have free will, but that's probably a fantasy and its either randomness or determinism or a mixture. But to be honest I think its just determinism because "inherent" randomness doesn't make intuitive sense to me at any level. So I would tend to agree with your friend; if the universe were recreated with the same particles colliding at the start in the same way, then yeah the same stuff would happen. What you do today would be the same too; even if you believe you have control, that's just an illusion of sorts.
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On March 31 2014 06:46 radscorpion9 wrote:Show nested quote +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. As a physics student I have to interject I think you're being a bit too absolutist about what the theory actually says. All we have is a (phenomenally) successful model that operates on the principle that certain observables, like position or momentum, can only be determined in the form of an average (or expectation) value; or that the location of a quanton over all space is described by a normalized probability distribution.
As a physics student myself, your interjection was not in any way opposed to what I wrote.
The world is seemingly not absolutely predictable. A lot of things happen in similar but not necessarily identical ways when you repeat them. On a big scale, the fluctuations from the expected value is not always noticable.
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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.
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On March 31 2014 06:46 radscorpion9 wrote:Show nested quote +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. As a physics student I have to interject I think you're being a bit too absolutist about what the theory actually says. All we have is a (phenomenally) successful model that operates on the principle that certain observables, like position or momentum, can only be determined in the form of an average (or expectation) value; or that the location of a quanton over all space is described by a normalized probability distribution. But just because the model works well by viewing the distribution as being random, I don't think it necessarily means that the core mechanism by which an electron "chooses" to be in a certain state is literally random. There could easily be many hidden variables that operate on the wavefunction, which we are unaware of yet. Just like if you imagine rolling a die; the interaction of the die with air molecules, the table, the momentum and spin imparted by your hand, can all combine to create something seemingly random. And of course, if we created a theory describing how the die lands, it would be very successful to describe it as a random process. Does this mean that the underlying mechanisms are random? I don't think we can infer that. If you knew what all of these variables were, you could almost certainly predict how the die lands each time. I think science is far from saying anything about whether the universe is deterministic or random at its core. Of course there is also the uncertainty principle; but remember this doesn't say anything about whether a process is random or not. All it means is that we can't *measure* position and momentum both with exacting precision (below a certain threshold); it doesn't say or imply anything about what the underlying mechanisms are that make this determination impossible. For example (as I learned), if you shorten a wave so that it only has one peak, it becomes impossible to measure the wavelength because you don't have enough information. But with one peak, you can clearly determine position. There is no randomness involved here; just a fundamental limitation of dealing with waves. --- Anyway to the OP: I'm not absolutely sure whether the universe is fundamentally deterministic or not. I like to think we have free will, but that's probably a fantasy and its either randomness or determinism or a mixture. But to be honest I think its just determinism because "inherent" randomness doesn't make intuitive sense to me at any level. So I would tend to agree with your friend; if the universe were recreated with the same particles colliding at the start in the same way, then yeah the same stuff would happen. What you do today would be the same too; even if you believe you have control, that's just an illusion of sorts.
Thanks. This is what I thought but I don't have the background to say what you just said so eloquently.
On March 31 2014 07:25 neptunusfisk wrote:Show nested quote +On March 31 2014 06:46 radscorpion9 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. As a physics student I have to interject I think you're being a bit too absolutist about what the theory actually says. All we have is a (phenomenally) successful model that operates on the principle that certain observables, like position or momentum, can only be determined in the form of an average (or expectation) value; or that the location of a quanton over all space is described by a normalized probability distribution. As a physics student myself, your interjection was not in any way opposed to what I wrote. The world is seemingly not absolutely predictable. A lot of things happen in similar but not necessarily identical ways when you repeat them. On a big scale, the fluctuations from the expected value is not always noticable.
You said the Universe was definitely non-deterministc.
He said it might be deterministic.
That's the opposition.
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You can't divorce the free will discussion entirely from science, because it is all about the conflict between people's subjective experience of being free to make choices, and how physics informs us that the universe runs more or less like clockwork, without any sort of mechanism to make free will possible.
Your friend's big bang argument is questionable, because we're really not sure if what he's saying is true. There seems to be a probabilistic element to nature, which would mean that if you could hypothetically rewind, restart or reduplicate the universe, you would get different RNG and thus different outcomes.
That said, your response seems to be entirely missing the point. Of course, our existence affects the future - that much is trivial, but the same could be said about a lake, and nobody would say a lake has free will. The question is whether we really are making choices, in a meaningful sense, or if we are just sophisticated meat automatons.
One argument for the latter position goes as follows; take an atom. We know the laws which govern it - electromagnetic forces, etcetera. So if you look at any individual atom in isolation, it's no more special than the ball in a pinball game. If you now take a bunch of atoms instead, none of this stops being true - every individual atom in a human body behaves just as mechanically. This means that, if there is no secret ingredient exempt from this sort of causality somewhere in people, then people cannot have free will in any sense that a computer program doesn't.
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On March 31 2014 06:46 radscorpion9 wrote:Show nested quote +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. As a physics student I have to interject I think you're being a bit too absolutist about what the theory actually says. All we have is a (phenomenally) successful model that operates on the principle that certain observables, like position or momentum, can only be determined in the form of an average (or expectation) value; or that the location of a quanton over all space is described by a normalized probability distribution. But just because the model works well by viewing the distribution as being random, I don't think it necessarily means that the core mechanism by which an electron "chooses" to be in a certain state is literally random. There could easily be many hidden variables that operate on the wavefunction, which we are unaware of yet. Just like if you imagine rolling a die; the interaction of the die with air molecules, the table, the momentum and spin imparted by your hand, can all combine to create something seemingly random. And of course, if we created a theory describing how the die lands, it would be very successful to describe it as a random process. Does this mean that the underlying mechanisms are random? I don't think we can infer that. If you knew what all of these variables were, you could almost certainly predict how the die lands each time. I think science is far from saying anything about whether the universe is deterministic or random at its core. Of course there is also the uncertainty principle; but remember this doesn't say anything about whether a process is random or not. All it means is that we can't *measure* position and momentum both with exacting precision (below a certain threshold); it doesn't say or imply anything about what the underlying mechanisms are that make this determination impossible. For example (as I learned), if you shorten a wave so that it only has one peak, it becomes impossible to measure the wavelength because you don't have enough information. But with one peak, you can clearly determine position. There is no randomness involved here; just a fundamental limitation of dealing with waves. --- Anyway to the OP: I'm not absolutely sure whether the universe is fundamentally deterministic or not. I like to think we have free will, but that's probably a fantasy and its either randomness or determinism or a mixture. But to be honest I think its just determinism because "inherent" randomness doesn't make intuitive sense to me at any level. So I would tend to agree with your friend; if the universe were recreated with the same particles colliding at the start in the same way, then yeah the same stuff would happen. What you do today would be the same too; even if you believe you have control, that's just an illusion of sorts.
It's always funny to me that people learned in physics seem to be the group most opposed to quantum mechanics or at least most open to the idea that it might not be a good expression of the source code of the universe, so to speak.
Hidden variable theories are an intriguing and even enchanting idea - something that really clicks with all the "rest" of physics that we understand. Everything works just so in a fully understandable manner - who wouldn't want that? The problem with hidden variable theories is that Bell's theorem can be used to outright disqualify 99% of them, and the other 1% depend on things which are interesting but tend to be signs of a failed system (tachyons and other explicit faster-than-light violations).
The beauty of your analogy with the die and its predictability is that it's all true. The flaw with the analogy is that some things are left out and some assumptions unnamed. Dice are "Newtonian" objects like baseball bats, pots and pans, boulders etc. Our whole life experience as humans is in interacting with these objects and expecting certain behaviors out of them. Unfortunately, our concept of a die as a Newtonian object is flawed, it is really a big mashup of subatomic particles, each with their own wave function - and the interaction of all those wave functions coalescing is what gives the die its Newtonian feel, its predictability, its tendency to act in the way it does.
Your arguments against randomness and your seeing it as unintuitive are perhaps worth reconsidering. As with all physics, terminology gets used and muddled and confused after a while - and it becomes a huge semantic clusterfuck. Randomness isn't all "truly" random. When humans think of something "truly" random, we think of each branch or possibility as having equal likelihood. This is anathema to our thinking and continued existence! If we can't predict things, we can't make any sense of our universe whatsoever - and that's a detriment to our ability to survive it.
But the vast majority of randomness in the universe isn't of this fashion, it's heavily biased. The universe isn't a delirious hallway of 50-50, it's full of 90-10 and 70-30. This is why things are predictable, because even the smallest degree of bias multiplied by millions and billions of subatomic particles will come out being 99.9999...95% - pretty much just the way we want it.
I'd also like to mention your statement about the uncertainty principle. You argue that it doesn't imply randomness, just lack of information. But that lack of information is not due to practical constraints like money, it is due to a fundamental aspect of the universe. This fundamental inherent property of the universe makes it impossible to measure certain things even in thought experiments - this forces us to ask what the possible values are and to assign likelihoods to those values (likelihoods which, fortunately, we can predict with incredible accuracy).
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If one particle, one second after the big bang, goes left instead of right, up instead of down, forwards instead of backwards, then entire universe could change fundamentally. When the universe is that small, quantum laws apply and thus the smallest change can have a very large effect. You could calculate the possibility of producing the exact same universe, but it would be infinitesimally small.
Reproducing our universe, assuming we could create new universes, would take an eternity. Eventually yes, we could, but I'm not sure anyone would be around to see it. Even if the initial conditions are exactly the same, some small event a million years after the big bang could have a massive impact. Imagine if the comet/asteroid that wiped out the dinosaurs got nudged just enough so it missed, it would only have to be nudged a few inches, long enough before it was due to hit, and boom.... completely different outcome.
The confluence of unlikely events that lead to this particular group of human beings, having this conversation, stretching across 13.8 billion years, is staggering. you simply couldn't reproduce it from scratch in a timely manner. You couldn't just rewind the tape and let it run again.
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Another student of physics, I'd like to interject also :D
First off, talking about the big bang as if it's some sort of weird cosmological phenomenon somewhat underplays just how little we understand the mechanisms of the formation of physical laws. There are physical theories out there that conclude the symmetry of time and space need not be conserved at all points in time. What this implies is that physical laws and constants that we use today may not have been the same as they were during the big bang. So, while the OP is a very interesting thought experiment, the notion of "if we can replicate the big bang" is rather shaky.
Second, I'd like to talk about the uncertainty principles, if I may, since this is currently my area of research and I'd like to think that I'm somewhat knowledgeable about it. The oft-quoted Heisenberg principle doesn't imply a non deterministic or a deterministic universe, in fact, it is simply a mathematical conclusion of empirically observed quantum observables (this sentence made more sense in my head, all things considered). The statement goes something like "if the operators associated with two observables do not commute (as is the case with position and momentum), then collapsing one wave function flattens the other one". It makes no references to *how* you observe an observable, it makes no reference to how the wave actually collapses. There's a great deal of contention of that bit of physics, and I could not give you a proper description (yet.. this is my area of research and I'm positively giddy about it) of how a wave function collapses. It could be utterly random in the most basic sense. It could be (as I suspect, but cannot prove quite yet) deterministic, yet for all intents and purposes could be modeled brilliantly as a random system (as we do now, to stunning success).
Consider, for instance, a random number generator. Anyone that studies compsci will tell you that there's no good way to make a truly random generator, but you can get pretty darned close. That's what some people suspect (we call this train of thought, btw, the realist interpretation of QM), in that nature is never truly random, but some small bits behave as if they are random to people that try to observe them. Then there's another camp (the orthodox interpretation) that says that nature is random, and there's no good way to qualitatively explain the phenomenon of wave collapse.
That's how I like to think of the issue of self determination: it might or might not exist, but both possibles regimes are so close to each other that practically it is impossible to make the distinction.
The issue of "is physics deterministic" is not something that we can answer at this point, however. Certainly it behaves very chaotically at the smallest of scales, but chaos is not necessarily random, either.
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On March 31 2014 13:48 NuclearVII wrote:
It makes no references to *how* you observe an observable, it makes no reference to how the wave actually collapses. There's a great deal of contention of that bit of physics, and I could not give you a proper description (yet.. this is my area of research and I'm positively giddy about it) of how a wave function collapses. It could be utterly random in the most basic sense. It could be (as I suspect, but cannot prove quite yet) deterministic, yet for all intents and purposes could be modeled brilliantly as a random system (as we do now, to stunning success).
Consider, for instance, a random number generator. Anyone that studies compsci will tell you that there's no good way to make a truly random generator, but you can get pretty darned close. That's what some people suspect (we call this train of thought, btw, the realist interpretation of QM), in that nature is never truly random, but some small bits behave as if they are random to people that try to observe them. Then there's another camp (the orthodox interpretation) that says that nature is random, and there's no good way to qualitatively explain the phenomenon of wave collapse.
You suspect that wave functions collapse deterministically. You suspect that there is never any true non-deterministic event - only seemingly non-deterministic events. Somewhere hiding behind all these seemingly random events are mechanisms that determine the outcome of things (this is starting to sound like hidden variable theories).
What is it that invests you in these ideas? It'd be nice if there was something "underneath" the quantum veil that we could point at and suddenly fully predict all manner of phenomenon without the need for probability. It'd be more intuitive if the universe was truly a clockwork mechanism where we could trace the actions and reactions all the way down to the smallest scale. But with every passing day, it looks more and more like QM is not hiding a hidden variable theory or any other such phenomenon. The ludicrous accuracy and success of QM as a predictive theory makes it seem, at the very least, highly unlikely that something entirely different is going on. What is it that has you convinced that QM is a masterfully-crafted shell game?
It seems unscientific to be of the opinion "yes, there is every indication that it works this way, but we're convinced that it works a totally different way." All the evidence and all the findings so far point towards the universe using probability as a basic mechanism. All the arguments ever levied against it (championed by some of the most premiere geniuses in human history, even) have been laid low so far. The preponderance of evidence is stacked up to seemingly insurmountable heights. What has you so convinced that it works differently than it appears to work?
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These are all excellent questions, I'll try to address them point by point.
What is it that invests you in these ideas? It'd be nice if there was something "underneath" the quantum veil that we could point at and suddenly fully predict all manner of phenomenon without the need for probability. It'd be more intuitive if the universe was truly a clockwork mechanism where we could trace the actions and reactions all the way down to the smallest scale.
It would certainly be very nice if the universe was fundamentally deterministic, however, this isn't my particular reason. No one with half a brain could contest that our current formulation of QM is functional. It works very well and has high predictive power in large ensemble scenarios (condensed matter physicists can testify to that).
However, there are issues. The biggest one (and what I'm working on atm) is the problem of measurement, and what constitutes as a measurement and what does not. This is not a recent problem, in fact, Heisenberg formulated this exact issue in his paper that gave a quantitative description of his uncertainty principle (it's called the Heisenberg Noise-Disturbance Principle). Heisenberg noted that, yes, measurement seemed to collapse wave functions seemingly at random, but we had no idea of what exactly constituted as a measurement, or how much a measurement would have an effect on the state in question. We have qualitative descriptions of it, certainly, but not a mathematical, physical one. In fact, with every passing day, we get problems that sort of fall in the middle, when you ask questions like "what if I measure my system a little bit", physics (or, at least, our current version of quantum theory) is unable to give a good enough answer (if you want some reading, look at the weak measurement experiments done recently). We have physical instances for which the Schrodinger equation should be enough, but is not.
Back to the original question. I think (this is less of a I-did-a-back-of-the-envelope-calculation and more of a gut feeling, but wth) that having an incomplete theory of QM is a bit of an issue. Certainly there might be regimes in which an observation theory would be of vital importance in understanding how a state evolves in time. It might even have practical applications (but, probably not :D).
What is it that has you convinced that QM is a masterfully-crafted shell game?
Ah. Well, I don't. I think QM is correct, there's no doubt about that. I am simply of the opinion that it is seemingly incomplete, and most theoretical physicists are of the same opinion. How we end up completing QM is a different question entirely. Right now, there's no consensus with regards to this question, and it's an area of very active research.
It seems unscientific to be of the opinion "yes, there is every indication that it works this way, but we're convinced that it works a totally different way."
Well, here's the thing - we don't know either way. It seems like it might be random. That's it. But there's also indications that it might *not* be random. This is more of an experimental question, sadly, because designing experiments that test quantum measurement problems are bloody hard. Not only can't I answer the question "Why does a wave function collapse", but I also can't answer "how does it collapse". It stands to reasons that they might be linked. But they might not be.
All the arguments ever levied against it (championed by some of the most premiere geniuses in human history, even) have been laid low so far.
I'm going to have to correct you on that, sadly. There are issues with QM, and, in more generalized form, QFT. For one thing, it doesn't agree with General Relativity. Quantum mechanics are very very very true, but they are also very arguably not complete.
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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:
On March 31 2014 07:31 neptunusfisk wrote:Show nested quote +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.
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EPT
