quantum mechanical interference?

cognitive science has a long way to go before we realise how predictable we are, and by that time our brains will have evolved

probailistic > deterministic imo

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Originally posted by occrider Exactly . My argument for welfare ... basic necessities and beyond that no one should be FORCED to provide more. Done and done!

lol i just owned myself

but i hope also you see a difference in a totalitarian state and welfare taxes

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Originally posted by DigiNut And the only thing I say is that you are factually wrong and don't understand the counter-argument. It is NOT possible, not even theoretically, because you can't know the contents of an infinite set! Also, you can't predict random variables, no matter what you say. It is not a practical limitation - it is a theoretical impossibility!

Okay i'm not a scientist and i haven't philosophized very much on this, but i think that there is no such thing as a _truly_ random thing. yes there may be impossible to predict, but IF you theoretically knew all variables, and you knew how to interpret them, you COULD predict a "random" thing... i tried to find something on google to backup my statement but i didn't find any... but i will continue to search and i will also ask my physics/math teacher when schools starts again...

Edit:

And then comes one more interesting thing, everything in this world is predictable, so _theretically_ can we look into the feuture....

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Originally posted by NeoPhono I'm going to be anal here (computer engineer in me coming out), and yes this is a little off-topic. The Heisenberg uncertainty principle only relates to actions on a quantum level, not a macroscopic one. It states that the more precisely a position is known, the less precisely the momentum is known. Actually though, this has been under quite a lot of debate recently, as this postulate was constructed before much of what we know of quantum mechanics was known. Today it is believed that you can know both position and momentum of subatomic particles to such a high percentage of probability that you can in fact know both position and momentum for "practical" purposes. My main point is that it only applies to non-macroscopic applications. It would suck if you saw a car coming towards you and could tell where it was, but not how fast it was coming at you. I personally think that the unertainty principle will one day be disproven, or at least pushed back to a realm where our oberservation abilities do not allow clear perception. Is our universe deterministic? I don't know, but I find it very hard to concede that it is purely indeterminite. Star Trek transporters...here we come!!!

There are some examples where HUP is detectable on a macro level. Aside from the optical experiment Diginut mentioned, there's also the Tunnel Diode. The very principle upon which that diode works is that the positions of the electrons aren't 100% certain, and that they can disappear and reappear somewhere else. Basically, you have a diode with a very narrow depleted region, so the electrons keep jumping from n to p area and vice-versa. Once you apply reverse voltage to it, the electrons keep reappearing on one side more frequently, and you get the electric current.

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Just on a side note, may people state the uncertainty principle as having to do with oberservation. In example, someone will say "the act of observation changes the state of a function, and makes measuring it accurately impossible." That is actually untrue, as even without observation, it has been shown to be impossible to know both position and momentum.

Heisenberg's uncertainty principle is closely related to the wave nature of particles. Each particle has dual nature, meaning it is both a wave and a particle at the same time. Now, once you get to the quantum level, particles are no longer deterministic solid blocks, they're like fuzzy areas inside which the particle exists but cannot be pinpointed. Sort of concentric spheres where each of those spheres contains the certain probability a particle pops into existance in it. That probability drops greatly with distance, so a chance of an object disappearing and reappearing far away is infinitesimally small, but still existant. So an electron can disappear and reappear half way across the universe in an instant. The place where the particle will reappear is completely random and dependant only on the distance, it can in no way be predicted.

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If you're interested in this kind of "stuff," I recommend read about the EPR paradox, the Bell inequality or the hidden variable theory...all very intersting, almost philosphical science questions along these lines.

I certainly will, thanx.

___________________
1+1=10

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Originally posted by St_Andrew Okay i'm not a scientist and i haven't philosophized very much on this, but i think that there is no such thing as a _truly_ random thing. yes there may be impossible to predict, but IF you theoretically knew all variables, and you knew how to interpret them, you COULD predict a "random" thing... i tried to find something on google to backup my statement but i didn't find any... but i will continue to search and i will also ask my physics/math teacher when schools starts again...

You're right, you're not a scientist. Trust me on this, random behaviour is a known thing, there are entire fields of math and science dedicated to this, entire textbooks written on random number theory and probability and stuff. You can't theoretically know all variables, and you can't predict a random thing. No matter how you try to explain it, you just can't!

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And then comes one more interesting thing, everything in this world is predictable, so _theretically_ can we look into the feuture....

Okay, all you did was repeat your original statement which was essentially debunked - let's avoid circular reasoning here, please.

You ought to read about chaos theory... might teach you a thing or two about how even determinism implies randomness. I don't know a hell of a lot about chaos theory myself, but it's very interesting and might give you some insight into the things we're discussing here.

Tito: Thanks, you obviously have a much clearer understanding of this than I do and your explanations/examples are way better.

___________________
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2009-06-18 - DJ Annoying @ People Need To Know Where I'll Be
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Originally posted by DigiNut Tito: Thanks, you obviously have a much clearer understanding of this than I do and your explanations/examples are way better.

Heh, I was kinda thinking the same about you. I guess it's the real ultimate power, ee style. We're totally awesome and cool.

http://www.rpi.edu/~harmsj/RUPEE/

___________________
1+1=10

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Originally posted by DigiNut You're right, you're not a scientist. Trust me on this, random behaviour is a known thing, there are entire fields of math and science dedicated to this, entire textbooks written on random number theory and probability and stuff. You can't theoretically know all variables, and you can't predict a random thing. No matter how you try to explain it, you just can't! Okay, all you did was repeat your original statement which was essentially debunked - let's avoid circular reasoning here, please. You ought to read about chaos theory... might teach you a thing or two about how even determinism implies randomness. I don't know a hell of a lot about chaos theory myself, but it's very interesting and might give you some insight into the things we're discussing here. Tito: Thanks, you obviously have a much clearer understanding of this than I do and your explanations/examples are way better.

hmm okay i will read some more about it and see if you convinced me (cause i'm not convinced yet..)... =) sorry for being stupid at this point

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Originally posted by St_Andrew hmm okay i will read some more about it and see if you convinced me (cause i'm not convinced yet..)... =) sorry for being stupid at this point

Good lad! http://www.duke.edu/~mjd/chaos/chaosh.html might be a good starting point, if you haven't found it already on google.

Note: try not to let it convince you that determinism really exists - the point is that things may be predictable in the long term (like human behaviour in general in a large society), but are a result of much randomness in the short term (the individual's own choices).

People so readily dismiss quantum variation as being meaningless on a macro scale, but fundamental chaos theory states even the smallest change could cause significantly large changes in a complex enough system. I think we have to believe that randomness exists in nature when one of the largest fields in modern mathematics is dedicated solely to it.

Hope you get convinced! The universe is an unpredictable place!

___________________
My party schedule:
2009-02-21 - DJ Attention @ I'm So Popular
2009-06-18 - DJ Annoying @ People Need To Know Where I'll Be
2012-11-32 - DJ Insufferable ɸ Or At Least the Stalkers I Complain About
2048-06-66 - Spastic & Whocares ¶ Although I'm Actually Flattered
9999-45-81 - Tweaker Gimp ☼ I Probably Won't Even Go To This But I Have To Make Sure I Fill Up All The Available Space Here

Last edited by DigiNut on Jan-02-2004 at 15:01

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Originally posted by DigiNut Good lad! http://www.duke.edu/~mjd/chaos/chaosh.html might be a good starting point, if you haven't found it already on google. People so readily dismiss quantum variation as being meaningless on a macro scale, but fundamental chaos theory states even the smallest change could cause significantly large changes in a complex enough system. I think we have to believe that randomness exists in nature when one of the largest fields in modern mathematics is dedicated solely to it. Hope you get convinced! The universe is an unpredictable place!

i have already read it

but as it doesn't really disagree with my theory, that even on a macro scale is it possible to predict things, THEORETICALLY. but yes i realize that it is highly unbelievable that we could ever do that, but i'm speaking theory now... got some link that kills that theory, i would gladly read it

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Originally posted by St_Andrew i have already read it but as it doesn't really disagree with my theory, that even on a macro scale is it possible to predict things, THEORETICALLY. but yes i realize that it is highly unbelievable that we could ever do that, but i'm speaking theory now... got some link that kills that theory, i would gladly read it

Individuals are the "micro scale" of society.

Societal trends - unemployment, poverty, crime, GDP, stock trends - they might be predictable in a long term sense - but those are all the results of individual variances or choices.

Even chaos theory, however, does not apply long-term trends as being completely deterministic - its application is to determine things on a micro scale to a sufficiently high probability that you are "beating the odds" so to speak - and on a very long (infinite) timeline, you will always "win" when you're beating the odds.

Think casinos - they know that, in the long term, they will make money. How? They can't predict which individuals will win money and which will lose. The slot machines, the blackjack games, they are all random individual instances. But the casino knows that in general, the odds are against their players and that the house will come out ahead. That is a very elementary application of statistics - long-term forecasting.

Long-term forecasting is not infallible - some casinos have lost money due to simple bad luck. But short-term forecasting, now that is a science that's been studied for years and years and even though we can always get closer, we can never, even in theory, get it perfect.

Edit: I should put it this way. It's like a limit, in calculus. When we say that the limit of a function is 1, that does not mean that the function can ever reach 1, even theoretically. If we take 1 - exp(x), we can never actually come up with a value of x that will make the function equal to 1. This is a mathematical construct, I realize, but when you read about chaos theory and long-term forecasting, that's how it works. You set a threshold, you say that okay, once we know something to 95% certainty, then that's good enough. But in order for the trapped-specimen analogy to work, we have to assume that 100% certainty is possible, and it's not - we can get ever closer to that 100% by knowing more, but we can never know everything, and hence never reach that 100%.

In fact, when you try to forecast (predict), present-state data is not enough. You need past-state data. The more you have, the more accurate your prediction is. But if we assume that the universe is infinite (not 5000 years old ), we could never have enough past-state data to do the prediction!

If something isn't 100% predictable, there must be randomness somewhere, which is what I call choice!

___________________
My party schedule:
2009-02-21 - DJ Attention @ I'm So Popular
2009-06-18 - DJ Annoying @ People Need To Know Where I'll Be
2012-11-32 - DJ Insufferable ɸ Or At Least the Stalkers I Complain About
2048-06-66 - Spastic & Whocares ¶ Although I'm Actually Flattered
9999-45-81 - Tweaker Gimp ☼ I Probably Won't Even Go To This But I Have To Make Sure I Fill Up All The Available Space Here

Last edited by DigiNut on Jan-02-2004 at 16:36

quote:

Originally posted by St_Andrew i have already read it but as it doesn't really disagree with my theory, that even on a macro scale is it possible to predict things, THEORETICALLY. but yes i realize that it is highly unbelievable that we could ever do that, but i'm speaking theory now... got some link that kills that theory, i would gladly read it

Even in theory you can't predict everything that will happen with absolute certainty. Let's assume that you know everything about the current state of the universe. If you are predicting general trends on a macro-scale, then your initial short-term predictions will turn out correctly with almost 100% certainty (notice that I said almost, the limit is 100%, but it is never reached). But as you start predicting events that happen further away in the future, quantum fluctuations will get in the way, and the probability of you making a correct assumption will start to drop towards 0. Even closed systems are subject to these fluctuations, and even they cannot be predicted with absolute certainty.

Here is a little example of that. Take a human and put him in a closed system, one where you control every input that human has. Now, let's suppose that you know the exact state of every subatomic particle that makes up that human. Now, if there weren't any quantum fluctuations, since you are controlling the input and since you know the exact state of the individual, you should predict the actions of that individual with a 100% certainty. But, now, when you take quantum fluctuations into account, things become different. Consider a neuron that is about to recieve a stimulus, which will result in that neuron fireing an impulse. One or two electrons jump to a lower energy level because of the quantum fluctuation and that neuron no longer fires that impulse. From that point on, neurons start behaving slightly differently than your original prediction, although the general functions of the neural net, and therefore the reactions of that human, are more or less the same. But, as time passes by, their behaviour starts becoming more and more unpredictable. In a few days/weeks/whatever, your theoretical model is no longer applicable to the real situation.

___________________
1+1=10

Gee, a thread can certainly get somewhere over the course of a week. I have some comments which I'll try to present in short:

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Originally posted by DigiNut ... I'm really against using any sort of scientific principles in this "free choice" argument - any qualified mathematician or scientist will tell you that the only certainty is randomness - pure determinism does not exist in nature. ...

I don't know your definition of "qualified", but I work as a researcher and teacher at a university in the field of (yes) decision theory and probability. And I would never dream of stating dogmatically that pure determinism does not exist in nature (and, yes, I know about HUP and quantum mechanics).

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Originally posted by DigiNut ... for now, I say that there are too many things wrong with the determinism concept: 1. There is an infinite set of variables and we can never figure out an infinite state. 2. There is a finite amount of uncertainty in those variables that we can never get around. 3. Even if we could get around 1 and 2, there is still visible random behaviour, i.e. as shown in the pinhole experiment. Even if you could find an exact state at one instant in time, the state at the next instant in time is random.

To take these one at the time:
1: In theory we can know the state of an infinite set of variables, if we can come up with a model that explains their relation flawlessly. I do not propose we can do so currently for even sets of variables with moderately complex interaction, nor that we may ever reach technical efficacy to do so in the future, but you certainly can come up with infinite sets of variables and models that describe their correlation perfectly.
2: If you assume that science has achieved *the* explanation of nature, and that we have in quantum mechanics/superstring theory *the* final theory of science, then you may be entitled to say that all things are uncertain. However, even under this assumption there are other interpretations of quantum mechanical phenomenon than the "particles are both waves and particles"-explanation, which indeed imply randomness. Some of these interpretations *are* deterministic, yet the factors that would allow us to predict are not directly observable to us. (For one - excellent, I might add - read on such a theory, see David Deutsch "The Fabric of Reality".)
3: The pinhole experiment is covered in Deutsch book, and he presents arguments as to why it is not necessarily a random phenomenon, only that we cannot observe all the involved factors, except through the experiment itself.

On a more general level: We both agree that Andrews argument is flawed, but we choose different paths of counter argument. You choose to attack his premises - that things are deterministic - and I momentarily accept the premises and say that they, logically, lead to the destruction of his point. Therefore, I do can say that the outcome of a coin flip is deterministic, as it is in conformance with the premises that the thread was started with, and I have momentarily accepted them.