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Fate

Whether or not you subscribe to the notion of fate or whether you think it's preposterous, you can't deny that it makes for rather interesting thought experiments. Ever since about senior year of high school, I've held onto the idea that it's rather plausible for life to be predetermined. Barring any influence that somehow "exists" outside of reality, it's hard to sell that the fate of the universe is not predetermined.

For example, in a closed system, if I drop a handful of quarters, and then closely observe their resting positions, it is theoretically possible to determine the exact height of my hand at the drop and the exact position of every quarter in my hand. The restriction that keeps us from making such predictions is really only the fidelity of the measurement tools we have. For example, if you, in another test, carefully placed every quarter in the same location as in the first test, they would appear identical, but there is no way you could ever reproduce their exact locations, to the infinitesimally small accuracy necessary. Even if you could, the air molecules around the quarters would be in different positions relative to the quarters because of the different motion of your hand.

So, in theory, if you could positively know the exact location, velocity, and every other quantifiable attribute of any one subatomic particle in the entire universe, is it possible, then, to predict every attribute of every other subatomic particle in the universe?

Quantum physics seems to tell us that there is a certain randomness about. But if randomness exists, if there are no universal forces behind the behavior, and if the sub-elements of atoms really do behave in truly random ways, then why would it come to be that (for example) hydrogen atoms exist at one end of the universe, and identical hydrogen atoms exist at the other end? Hydrogen atoms didn't exist at the Big Bang. It was only after much time had passed that atoms and molecules began to form. If there were no physical laws governing that formation, why wouldn't we end up with a universe that isn't homogeneous (from a very large-scale perspective)? It makes sense to me that that randomness only seems random due to our inability to understand the causes and effects (so far).

So it follows that everything, down to the thoughts in my head, could be predetermined, and the fact that I'm thinking about them is as well, if it's just determined by the culmination of all the outside influences on my body up until this point.

Anyone have any insight on this?

There's only one thing I know for sure: we're all at risk for The Beetus.

Comments

( 26 comments — Leave a comment )
shirou
Aug. 21st, 2007 06:51 pm (UTC)
I will not speculate now on how consciousness comes into play, but I will say that if you assume that it does not, that there is no more to the universe than the physical, then you are making a rather large assumption. I will endeavor to explain a little quantum mechanics, since your description of it is grievously incorrect.

A particle (for example) exists in a quantum mechanical state. This state evolves in time in a manner which is both linear and deterministic. Note that the state is not something like "position" or "momentum," each of which specify only one aspect of the particle: the quantum state contains all the information about the particle.

Now let us attempt to measure an observable quantity such as position. The particle need not be in a well-defined position state prior to the measurement. For the sake of simplicity, let's assume there are two available positions, 0 and 1 (in some units). The particle may be 20% in state 0 and 80% in state 1. This is not possible in classical physics, but quantum physics allows it. When the measurement is made, the particle moves to a well-defined position state, state 0 with probability 1/5 and state 1 with probability 4/5 (roughly speaking... I'm down-playing the mathematics enormously). This process is highly non-linear and non-deterministic. Note, however, that the probabilities are well-defined, so it is not completely random.

Now, a few corrections to your post:

(1) You state it is the fidelity of our measurement tools that prevent us from learning everything about a particle to arbitrary precision. This is approximately true for macroscopic quantities but completely incorrect for microscopic ones. Consider again our particle. After I measure the particle's position, I choose to measure its momentum. When I do so, the particle will move into a well-defined momentum state. However, because the state of the particle has changed, it is no longer in a well-defined position state! If I make the position measurement again, I may not get the same result as I did before, even if the amount of time between measurements is arbitrarily small! The limitation on information is far more fundamental than the limitation on tools.

(2) Quantum physics describes a certain amount of randomness, but that in no way implies that universal forces are not responsible for the behavior of particles. I don't even understand how you got from the first statement to the second.

(3) Hydrogen atoms are identical everywhere because of how we define them. We define hydrogen to be an atom with exactly one proton. Hydrogen atoms everywhere have exactly one proton because, if it has more than one proton, it isn't hydrogen.

There are a lot of esoteric questions that arise from quantum mechanics. For example, what qualifies as a measurement? Barring a super-universal being making a measurement, the quantum mechanical state of the entire universe should evolve deterministically, so how do we reconcile the non-determinism withini it? There are just a couple of examples (albeit major ones) and I won't attempt to answer them. I have ideas but none that I feel are thought-out enough to share. I'm not trying to dismiss your ideas about fate and determinism, but I did want to correct the errors in your description of physics.
alruff
Aug. 21st, 2007 07:05 pm (UTC)
For your statement #2, I think he's talking about the Heisenberg Uncertainty Principle. Dead cat in a box and all that.

I don't mean to be overly defensive, but you might not want to call us laypeople "grievously incorrect" or state that we're making "rather large assumptions."

The question was really about whether we can predict fate and the implications thereof. I would take a stand, rather than speak with such condescension.
shirou
Aug. 21st, 2007 07:31 pm (UTC)
The Heisenberg uncertainty principle is what I described in statement (1). Schrodinger's cat is actually not about the uncertainty relation per se, but rather about the fact that the current state may be comprised of a weighted sum of observable states, so that the cat, prior to being observed, is in some mixture of the "alive" state and the "dead" state. This is what I described in my third paragraph, above.

I apologize if my diction is condescending. I admit that I could and probably should have omitted the term "grievously." Tone aside, my response was quite relevant. There are errors in the argument as presented, and while the conclusion may stand, the reasoning should be altered to more accurately reflect physics as we understand it.

I don't think the question is about whether or not humans can predict fate. Clearly we cannot. The question is: does fate exist, even though we will never be able to determine precisely the future of the universe? My opinion is that fate does not exist, at least not absolutely. I base this on spiritual and philosophical, not scientific, reasons. I do believe that there is more to the universe than the physical, I do believe that consciousness is more than the collective activity of neurological components, and I do believe in free will.
skate_or_die82
Aug. 21st, 2007 07:14 pm (UTC)
Nice icon. How do you like Persona 3?

R
shirou
Aug. 21st, 2007 07:32 pm (UTC)
I love it!
happinessiseasy
Aug. 21st, 2007 07:39 pm (UTC)
Thanks for your response. I was hoping someone would post something interesting. I may have made some incorrect assumptions, but I agree with Alex that it was a bit condescending to call my statement a "grievously incorrect" description. I never attempted to describe quantum mechanics. I merely stated that it seems to show randomness. This might be considered a misinformed assumption at worst.

Re: 1) I don't quite see how that's not a limitation of our tools. Our instruments are not able to measure both of those states (position and momentum) at the same time. If you theorize that it's impossible to, then that would mean that our tools are forever limited.

Re: 2) How can a force that does not produce deterministic behavior be predicted or described accurately? Also, randomness cannot be produced from non-randomness, lest it only seem random.

Re: 3) You're correct, but that's semantics. My point was that the atom we call hydrogen exists all over the universe. It didn't form on one side of the universe and not the other, as one would expect if the formation of elementary particles and their atomic aggregations were the product of randomness.

I would also like to add that assuming "there is no more to the universe than the physical" is no different than saying "I call everything that we can measure the effects of somehow 'physical.'" If we can't measure the effects, that gets into the question of what defines existence. A supreme deity that does not exert influence that we can detect I would call non-existent. If it does, I would call it physical. I include consciousness in this category as well.
shirou
Aug. 21st, 2007 07:59 pm (UTC)
I again apologize for my use of the term "grievously." I did not intend to be condescending.

(1) It's not a limitation of tools: it's more fundamental. The statement is not just that we cannot determine with arbitrary precision all the observable quantities. The statement is that even if we had the tools to determine each observable quantity to arbitrary precision independently, the system cannot exist simultaneously in a state with (for example) a well-defined position and momentum. Say that I do have two tools, X and P, which measure position and momentum with perfect accuracy. I use X to measure the position of a particle, which I now know completely. Immediately thereafter, I use P to measure the momentum of the particle, which I now know completely. Do I know both the position and the momentum? No. By measuring the momentum, I have forced the particle into a state with a well-defined momentum, and thus it no longer has a well-defined position. The original measurement made with X is no longer good. This is not a limitation of my tools, X and P, each of which does its job perfectly. It is a fundamental limitation: a particle cannot be in a state that has both a well-defined position and a well-defined momentum, regardless of what tools I have available to me.

(2) The evolution of a quantum-mechanical state is deterministic until a measurement is made. Only the act of observation forces a system to behave in a non-determinstic way, and even then the behavior is probabilistic, not random.

(3) The formation of elementary particles and their aggregations (a proton falls in the latter category, by the way) is not the product of randomness! You're (unintentionally) setting up a straw man by misrepresenting physics theory. That's what I was attempting to correct.

I use the word physical to mean "that which is described by physics."
happinessiseasy
Aug. 21st, 2007 08:12 pm (UTC)
1) Maybe a stupid question, but why can't you use X while someone else uses P simultaneously?

2) I think this is getting into the realm of my fundamental knowledge deficiency, so I'll take your word for that until I take a few more courses.

3) I realize it's not random, though. I'm apparently wrong in why it's not random, but my conclusion was that, if it's not, it must be deterministic.

physical: "that which is described by physics"
physics: "that which defines the physical"
shirou
Aug. 21st, 2007 08:43 pm (UTC)
You've had linear algebra, right? I have to use a small amount of math jargon to answer the question about using X and P simultaneously. In quantum mechanics, a measurement is taken by applying an operator to the quantum mechanical state. The operator may be thought of as a square matrix, and the state as a column vector. The new state that results after the measurement is an eigenvector of the matrix, and the value of the measurement is the corresponding eigenvalue.

Using X and P simultaneously is equivalent to using a single operator that gives both the position and momentum. However, what would be the eigenvalue of this operator? For each eigenvector there is only one corresponding eigenvalue, and the uncertainty relation tells us that any eigenstate of the position operator is not an eignstate of the momentum operator. Thus we see that using a single operator is not possible. We can do XP or PX, but we cannot somehow combine them into one.

I'm sorry that I don't have a more intuitive way to explain this, but often quantum mechanics defies intuition. At some point you just have do the math.

As an aside, simultaneity is a tricky concept. True simultaneity does not exist, in the sense that two events that one observer sees as simultaneous will not appear simultaneous to an observer in a different reference frame (special relativity). There's no need to introduce different reference frames to explain what we've been discussing, so I have avoided it, but I now feel like a bad physicist for using the word "simultaneous" so many times without clarifiying my meaning. :-)
happinessiseasy
Aug. 21st, 2007 08:56 pm (UTC)
Thanks. That's actually a great help.

Can simultaneity be thought of as a single-processor CPU, where events can seem to take place at the same time, but there is actually only one instruction executed at a time? Or is that oversimplifying it?
alruff
Aug. 21st, 2007 06:56 pm (UTC)
Let me address your assertions on instrument fidelity. The problem is that if you knew the place where something WAS, then you still have to determine where it will be. Unfortunately, that means that you are currently limited by the speed of electrons, which will mean that your calculations will lag behind reality by a good bit. Even if you use photons for computations, you will STILL lag behind reality by a good bit. No piece of machinery, no matter how great, will ever calculate the speed of reality in "real time."

Couple that with the fact that quantum physics states that observing a subatomic particle changes it, and you get a truly unpredictable equation.

Lastly, if you postulate that there is no god, and you accept the likelihood that humans will never be able to calculate the future through physics, then you have to arrive at the conclusion that no one will ever know our fates, even if they are predetermined.

So the question is, even if everything is fated to pass, why would it matter if said fate cannot be predicted?
happinessiseasy
Aug. 21st, 2007 07:43 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
I honestly am more concerned with The Beetus.

No, I think that for it to be provable that fate exists, we must be able to predict it. Otherwise, how do you prove it? If you can't prove it, it's a moot point.
bjbass
Aug. 21st, 2007 07:20 pm (UTC)
Part 1 -- Stocatsicism and Determinism
Not all closed systems are strictly deterministic. Your example may actually be one that is not. For some systems there can be large swings in the result due to tiny differences in initial conditions. You can keep improving your prediction by improving your knowledge of the initial conditions, but no matter how close you get, there are still uncertainties and unpredicted results.

Weather is such a system. Years ago they told us that all they needed for perfect weather prediction was more data and bigger computers. Now they have more data and huge computers and the five-day forecast is accurate except when it's not. Predicting next summer's rainfall is still a crapshoot.

The concept of stepping deeper and deeper into your knowledge of conditions without ever achieving resolution introduces the idea of fractals. Fractal systems have this independence of scale. If you look at one of those Mandelbrot patterns, and focus in on one little part of it and blow it up, and you see the same pattern. Focus on a little part again and blow it up and you see the same pattern.

If you look at the line between land and water on a beach, you can't tell if you're looking at an inch or a foot or a mile of beach. If you look at the structure in clouds, like you'd see from an airplane window as you fly through the cloud layer, you can't tell if you're looking at one foot by one foot or 100 feet by 100 feet. The same types of patterns -- not identical lumps, but statistically similar distributions of lumps -- occur at all scales. The patterns in turbulence -- the fluctuations you see in a smoke cloud for example -- are an excellent example of something that is ultimately deterministic but completely unpredictable.

Regarding quantum mechanics, I think the key concept for this discussion is fuzziness. If you've got ten atoms in excited states and you watch them for a certain length of time, you can predict how many will decay or relax, but not which ones. That doesn't mean it's not deterministic at some level, but just that it's too fuzzy to know exactly what's going on. So we're limited to statistical descriptions. I guess. Quantum land was always kind of like fairyland to me, and I'm not sure it has much to do with real life.
bjbass
Aug. 21st, 2007 07:25 pm (UTC)
Part 2 -- Predestination
Now considering predestination, it's hard to test, because any test you can dream up, and its results, might have been predestined. I think you have to look up from your science experiments and think more in terms of philosophy. Why would a supreme power set everything up like that? It'd be an awful lot of work.

Imagine being a game programmer. You write a complex game, with big people and little people and wizards and monsters and princesses, and you define the land they live in and the rules they live under in minute detail. But you do no random draws, and you don't allow a human player. You get your program finished, you run it, it goes "ding" and ends just as you knew it would, and you say "so what?" If there is a god, and if he is the creator, the only motivation he could have had for doing so would be to have some fun.

I believe that day to day things are not predestined but that major events are. I first believed this when Nixon went to China. As a young congressman, Nixon was on the House Unamerican Activities Committee under Joe McCarthy. He made a career out of baiting and unmasking communists. He really believed that international communism was a threat to our way of life, and he kept the Vietnam war going because he really feared that if we lost there, that communism would spread throughout Asia and the Pacific and would threaten California.

Going to China was not something that Richard Nixon would have ever thought of. But he did it. It was time, in the global scheme of things, for China to begin to open up, and Nixon was in the White House, so he had to go.

This solves a problem with time travel. What happens if you go back in time and change something? The answer is that it may cause a ripple but you can't change the flow of history. If you went back and shot Hitler, would WWII have been avoided? Of course not. WWII had to happen, and Goering or one of those guys would have taken over.
happinessiseasy
Aug. 21st, 2007 07:53 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
Not all closed systems are strictly deterministic.

If you define weather as a closed system, it is completely deterministic. Just because we don't have the data from every molecule in the atmosphere, doesn't mean that if you did, you couldn't predict it. I think you could with great certainty. Our weather knowledge is infinitesimally small compared to the knowledge I'm purported we'd need to know to make those kinds of predictions, though.

[a cloud of smoke being] ultimately deterministic but completely unpredictable.

Unpredictable using our current methods, yes. But if you look at a plume model in a video game, you would say the same thing if you didn't know it was a game. But we know because we wrote it that it is 100% predictable (within the closed system of the program). I'm putting forth the notion that everything is that predictable if you miraculously have all of the data.

I believe that day to day things are not predestined but that major events are.

I don't see anything occurring purely on Earth as a major event in the cosmic sense. Sociologically speaking, that could've been predetermined, but not by any mind-controlling force from outside of Earth (unless you count a 10^10000 particles all affecting the Earth at once as one giant force).

Time travel is bunk. Time doesn't move backwards. The problem is that if you go back in time, you change one thing and all of a sudden you don't invent a time machine anymore.

Besides, if someone invents a time machine before the end of human existence, why would they have not gone back to a time before now with it? wouldn't we already know of it?
alruff
Aug. 21st, 2007 08:34 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
No way! The time-travelers are secret police, led by bad actors who correct Earth's semi-wrongs from the shadows. And if a time-traveler changes something, the TimeCops go back and kill his parents. Duh, Jim!
bjbass
Aug. 21st, 2007 09:31 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
You're right that ultimately everything is deterministic. But that doesn't mean it's predictable. I wish I had the right words to describe this. There are some systems that, no matter how much information you have, it's not enough. Weather is such a system. No matter how much you know, it will always have surprises.

Unpredictable using our current methods, yes. But if you look at a plume model in a video game, you would say the same thing if you didn't know it was a game. But we know because we wrote it that it is 100% predictable. I create smoke models for missile simulations, which after all are just big video games. Until recent years, mine looked better than anything you'd see in movies or video games (although mine were impractical for those applications because they involve massive amounts of precalculated data, and in their 3D mode they don't render in real time. Yet.) In the last couple years, entertainment smoke models have become very realistic.

Atmospheric turbulence is what gives clouds their appearance. The smoke doesn't create the turbulence, it just makes it visible. Turbulence results from the viscosity of air. Big eddies form and move with the wind. They break into smaller and smaller eddies until, below a certain size, they dissipate. So at any time you have a distribution in time and space of these air bubbles of different sizes, densities, and temperatures, flowing in amongst each other and constantly changing. If you watched my model you'd see them flowing and changing. And, if I run it again and use the same initial seed, I'll get the same result. My turbulence is, as you say, entirely predictable.

But my model is not real turbulence. My program uses a Fourier technique to build and propagate the eddies. I wish I had written it, but I didn't, I just adapted it to this application. It essentially creates one possible reality out of the infinite set of possible realities.

Turbulence fields cannot be predicted. No matter how much you know.

There was an excellent book published 10 or 15 years ago called Chaos. You should read it, I think you'd really like it. I wouldn't be surprised if you could find it at a used book store for a buck or two. It deals with these questions in a much more elegant way than I ever could. Just off the top of my head I remember him talking about two entirely different problems: first, if you put a pendulum at the end of a pendulum at the end of a pendulum, by the time you get to five or six you have an amazingly complex system; and second, he talks about the erratic and seemingly random heartbeat patterns of arrhythmia.

bjbass
Aug. 21st, 2007 09:32 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
Of course I don't really believe in time travel. But if you read fiction, you have to have an alternative set of beliefs. It's no fun reading science fiction, or even a lot of mainstream fiction, if you don't believe in time travel and faster-than-light travel and telepathy and aliens in flying saucers and witches and vampires and wizards and dementors. So you suspend your rational real-world boring beliefs and bring out the alternative belief system.
happinessiseasy
Aug. 21st, 2007 11:01 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
Turbulence fields cannot be predicted. No matter how much you know.

So does this assume that if you had every possible bit of information from the end result of your simulation, you couldn't predict the Fourier sequence that produced it?

I think I still fundamentally disagree with that statement in theory alone. I agree in practicality. It's impossible to even fathom the amount of knowledge one would need, but you cannot deny that it is possible given every last ounce of information. And that's all my initial posting really meant.
shirou
Aug. 22nd, 2007 01:00 am (UTC)
Re: Part 1 -- Stocatsicism and Determinism
To correctly predict the dynamics of a closed chaotic system, you would require (1) the differential equations that govern the dynamics, (2) knowledge of the initial conditions to arbitrary precision, and (3) the ability to do the computations without any rounding. The system is deterministic but unpredictable. Even if we had (1) and (2) -- and we'll never have (2) -- we still cannot and will never do (3). Even the tiny error introduced by rounding in a computer will amplify along the strange (chaotic) attractor to such an extent that the final result will have little to no bearing on the real-life answer.

I agree that the system is deterministic, but chaotic systems absolutely defy prediction. The amount of information needed is not just unfathomable, it is actually infinite (think about storing an irrational number without rounding). Prediction is likewise not just unfathomable, but actually impossible.
bjbass
Aug. 22nd, 2007 03:04 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
Well said. Jim, look for that Chaos book. It's interesting and well-written and with your bent for science and philosophy, you are just the kind of person it was written for.
happinessiseasy
Aug. 22nd, 2007 03:20 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
Will do.
happinessiseasy
Aug. 22nd, 2007 03:29 pm (UTC)
Re: Part 1 -- Stocatsicism and Determinism
Noooooooooooooo! My plans for obtaining omniscience have been thwarted again!
alruff
Aug. 21st, 2007 08:35 pm (UTC)
Re: Part 2 -- Predestination
I like your game programmer analogy, but why factor in free will? For fun? What is God getting out of it that he wasn't getting before with no randomness? Extra fun?
bjbass
Aug. 22nd, 2007 03:03 pm (UTC)
Re: Part 2 -- Predestination
Fun, I guess. I have no idea what God's motivation was for creation, but to go to all that work and then have everything predestined seems kind of pointless. Boring. We all know that God hates boring.
happinessiseasy
Aug. 22nd, 2007 03:30 pm (UTC)
Re: Part 2 -- Predestination
Not Allah. Allah wants everything to be predictable. Yahweh is a bit fickle, though. I heard him bitchin at Odin the other day about it.
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