Predicting the future?

Ivan

Perhaps not the best place for this, but I figured it suited here the most...

Ok, some friends and I watched Donnie Darko. Its a really dark and sinister movie, which is filled with lots of tension but in the short run is based loosely around time travel and fate.

So we got to talking about suppose you could go back in time to the begining of the universe, ala the big bang. Now supposing you went back to this point in creation, that point where physics "comes into being" and you have this massively powerful super computer capable of trillions of calculations per nano-second.

Now suppose you then analyze the universe as it existed right there and then. You calculate the movement of each single atom moving outwards from the centre of the universe/big bang. You calculate interactions between atoms/molecules on the atomic level. You watch as two atoms spin dangerously close to each other and get got in each others "gravitational field" and spin closer together until eventually a molecule is formed. Now for the first million years or whatever you have your computer sitting there observing each individual atom/molecule's movement. Using your superbly powerful computer you can eventually predict the movement of each of these atoms.

Now another aspect, is it correct to assume that human decisions are as a result of previous experiences? Is it fair to say that if I grew up in another country, any country, England, America, or even another county? Would I be a different person? Obviously I would have certain traits in common with my current self. I would have black hair, brown eyes (or whatever colour my eyes are) I'd be tall etc. etc. But when you come down to it. Every decision I would have to make would come from my previous experience? If I was rich I might look down on poor people and as a result not give a poor guy some money outside a supermacs. And so on and so forth. I'm sure you can see where I'm going with this.

Basically what I'm suggesting is, given a spectacularly large enough computer, would it be possible to track and then predict atoms paths, and through a record of human experiences, would i be able to predict random affects in the universe such as collisions of asteroids, weather patterns on planets, even the creation of new stars/planets/black holes. AND by recording and analysing the experiences of humans, could I calculate human decisions.

Now if I was to lump the two of these together, surely I could predict the future. I could predict weather patterns, tectonic plate movement, an abused child shooting up a school, a car accident, anything?

Now if it is possible to predict the future? Wouldnt that mean that the future has to be set out, Fate has just been proven?

We are not in control of our own destiny's? Anything we do, we were going to do anyway, based on movements of atoms, and our own, chemically driven, thought patterns, based on our experiences?

Does this take all the fun out of our universe, does the knowledge that their is no randomness remove the hope for the future? Or is our lack of knowledge, our inability to predict the future, enough. Does it keep us on our toes? Does our not knowing what we are going to do next, even though it was destined to happen, leave us with some resemblance of "free will"?

Please help me, I feel like a man who has seen god and realised he has set the Universe on automatic and is gone off to play with his other toys.

Ivan

Damned if you do, bored if you dont.

daveirl

This post has been deleted.

Ivan

wow, that one seemingly harmless statement wrecks the entire theory. Did he prove this or is it a theory? How can you prove conclusively that because you know the speed of an atom you can know its exact position and vice versa, that seems illogical. I'm sure there is a fairly straight forward mathematical explanation but I cant find one.

daveirl

This post has been deleted.

Ivan

I did do a search, but didnt really find anything to conclusively prove this statement.

I've never done Quatum Mechanics so its a little out of my league, so if you could point me to a proof and/or explain it I would be extremely grateful.

Ivan

Ivan

Taken from
http://www.aip.org/history/heisenberg/p08c.htm

Heisenberg took this one step further: he challenged the notion of simple causality in nature, that every determinate cause in nature is followed by the resulting effect. Translated into "classical physics," this had meant that the future motion of a particle could be exactly predicted, or "determined," from a knowledge of its present position and momentum and all of the forces acting upon it. The uncertainty principle denies this, Heisenberg declared, because one cannot know the precise position and momentum of a particle at a given instant, so its future cannot be determined. One cannot calculate the precise future motion of a particle, but only a range of possibilities for the future motion of the particle. (However, the probabilities of each motion, and the distribution of many particles following these motions, could be calculated exactly from Schrödinger's wave equation.)

Ok so if you cannot predict the movement of an atom but only the possible movements of an atom thats fair enough. Assuming thats true, it then goes on to state that using Schrödinger's wave equation you could calculate "the probabilities of each motion" in effect calculate the "most likely" future movement of the atoms? Isnt that in effect saying, I'm predicting the future but only with a certain element of precision?

I.e. I'm 95% (or whatever) sure that this is whats going to happen. Basically you could predict events within reason, and my original premise still stands?

If you can predict the future (to any extent) doesnt that mean that our actions our predetermined?

It simple becomes, If you can predict the future (to any extent) doesnt that mean our actions are from a list of predetermined actions?

Ivan

DeVore

Theres a topic just been discussed entitled Free Will which you should read. basically the answers are:

1. Yes the uncertainty principle is not only provable but demonstrable.

2. No the world is not deterministic. Even if you could know all the position and speed of the atoms in the universe quantum mechanics has the Schrodingers cat experiment to deal with... quantum uncertainty comes into play.

Its worth looking at that thread though as it was all covered there. (its quite recent too).

DeV.

Koopa

heisenbergs uncertainty principle is due to flaws in our measurement methods (bouncing waves off particles to calculate their position, etc - it affects the particle)

it doesnt mean you cant "know" the position and velocity of a particle (despite what some current-day physicists might say), by other means - eg. prediction by computer, etc.
for example, suppose you bounced a wave off a particle to "see" its position, but you knew EXACTLY how your wave would affect the particle - then you could know the current position and velocity of that particle, breaking heisenbergs uncertainty principle

its a principle that relies on imperfect observation methods, and goes as far as saying "we will never have a better observation method" - which stupid to say at this time, we dont know whats possible

davej

heisenbergs uncertainty principle is due to flaws in our measurement methods (bouncing waves off particles to calculate their position, etc - it affects the particle)

But doesn't quantum mechanics also assert that particles have both wave characteristics AND point characteristics ?

but you knew EXACTLY how your wave would affect the particle

This is a bit of a chicken and egg scenario. How could you measure the exact characteristics of your probing wave ? By using another probing wave ?

davej

DeVore

Koopa I used to think that too but the problem is that you need an infinitely small wavelength to measure something at an exact instant (think of it in terms of shutter speed of a camera).

However energy (in the form of light particles) cannot have arbitrary wave lengths, they fall into the nearest "quanta"... a bit like electrons fall into the nearest "shell". the light wave can have a wavelength of 2 or 3 cm but not 2.5 (obviously this is an example, not actual numbers).

The higher the wavelength the more energy needed to create it and eventually this limits your ability to observe something any more precisely...


This except from Hawking explains it pretty well..

http://ideaplace.org/Chemistry/ChemMisc/HawkingC4.html

DeV.

Koopa

the problem is that you need an infinitely small wavelength to measure something at an exact instant (think of it in terms of shutter speed of a camera).

yeah i know, but what i was saying was, this is all based on what we currently know about particles/waves/stuff, we currently dont have a method of "predicting" particles or even measuring stuff like that without introducing an error, but that doesnt mean that one doesnt exist (and we might discover it in the future).
its like we're at the level of cavemen right now, and someone is saying "its NOT POSSIBLE to make light without fire" just because noone has invented a light bulb yet, or seen electricity

i understand the uncertainty principle, thats why i disagree with it

DeVore

Well I'd be a fool to say that it will never be found because throughout science we have made liars of ourselves over time...

But I seriously doubt it personally... I mean an AWFUL lot of physics would have to be thrown out (along with a fair bit of philosophy) if the Uncertainty Principle is found to be false...


Care to make a www.longbet.org on it?

DeV.

Koopa

davej:]
But doesn't quantum mechanics also assert that particles have both wave characteristics AND point characteristics ?

quantum mechanics can assert whatever it wants, it doesnt mean it giving you the full picture.
its just a set of rules that helps us predict some of what happens in the universe with our current knowledge, its by no means a complete explanation of the universe

you can think of a ripple in a pond caused by a stone being dropped into it, you can visualise it in three dimensions, but for something which could only observe the pond from one viewpoint directly above, you could write a set of equations that would hold true for the movement of each ripple that it sees (in the 2 dimensions it sees it in), it would still leave huge gaps in the 3d model of the ripples though, and thus definitely not be a complete description of the ripple (even in mathematical terms)


[edit] haha, sure, put it into that longbets website.. doubt anyone will agree with me though [/edit]

[edit2] to make this post clearer, ill add in this bit:
im not trying to answer the question "is the universe deterministic from our perspective?" , im trying to answer "is the universe deterministic?", from what i can see the answer to that has to be "yes", even if it may never be possible for us to predict the universe, i dont think it can really be "unpredictable" talking in the absolute sense [/edit2]

Snowball

Is the problem that Ivan is talking about not solvable by using multiple computers comunicating between each other? Then one could know the composition of the atom and the other could know the trogectory and speed. If they were fast enough could one not predict the future?

Oh but jst to shoot my self in the ass. Ivan, we were talking last week about decripting some encription algarithum (the prob is I cant remember the name of the encription) and the fact that it would be imposible because th computers needed would need more energy than it is possible to produce?

davej

you can think of a ripple in a pond caused by a stone being dropped into it,

Yes I agree with you that we may simply be akin to fish swimming around in a garden pond trying to figure out what's going on - but this argument can be used to refute everything! You can't successfully argue against metaphysics. For all we know we are sitting on the back of an infinite number of tortoises, one stacked beneath the other...


davej

Ivan

Originally posted by Koopa
quantum mechanics can assert whatever it wants, it doesnt mean it giving you the full picture.
its just a set of rules that helps us predict some of what happens in the universe with our current knowledge, its by no means a complete explanation of the universe

you can think of a ripple in a pond caused by a stone being dropped into it, you can visualise it in three dimensions, but for something which could only observe the pond from one viewpoint directly above, you could write a set of equations that would hold true for the movement of each ripple that it sees (in the 2 dimensions it sees it in), it would still leave huge gaps in the 3d model of the ripples though, and thus definitely not be a complete description of the ripple (even in mathematical terms)


[edit] haha, sure, put it into that longbets website.. doubt anyone will agree with me though [/edit]

Yes, in a nut shell. Just because Heisenberg stated we cannot measure the universe at the moment without disturbing it doesnt mean we may not in the future be able to.

As was said in Groundhog day, maybe god isnt all powerful he was simply around for a very long time. Maybe "God" isnt a supreme being, but merely someone with extremely advanced scientific methods. As a result of which not only is he able to predict the future, but alter it by altering the universe on the sub-atomic.

What I'm getting at though, and ye all seem to be missing it is :

If there is even the slightest chance - I.e even if Heisenberg is correct and you cannot predict a particles movement without altering its velocity/trajectory, ever! Even if the best you can ever hope for is to use Schrödinger's wave equation to calculate the most probable course for the particle to take. Wouldnt this mean, you are, in all terms predicting the future. And as a result, indirectly prove that fate exists?

Of course all theoretically.

Excuse my ignorance, but I have never studied quantum mechanics. The closest I've ever gotten, is the composition of light, so excuse me if I seem a little dim...

Ivan

bonkey

Originally posted by Ivan
If there is even the slightest chance - I.e even if Heisenberg is correct and you cannot predict a particles movement without altering its velocity/trajectory, ever! Even if the best you can ever hope for is to use Schrödinger's wave equation to calculate the most probable course for the particle to take. Wouldnt this mean, you are, in all terms predicting the future. And as a result, indirectly prove that fate exists?

OK...if all these things are true, then you are correct, but are phrasing your question in a very overcomplicated way. What you are effectively asking is :

"if the universe is actually deterministic, is it theoretically possible to determine it".

Obviously, the answer is yes.

However, if Heisenberg is correct, then the implications are weird and wonderful. You can never know the state you start from sufficiently accurately, and therefore cannot accurately model what will happen.

Does this mean that the universe is deterministic? Well, it doesnt actually say that it is or it isnt - and thats where the whole lovely can of worms comes in - because to date we have not found another way of answering that question. We can say that from our perspective the universe is non-deterministic, but that doesnt mean that it is.

jc

Koopa

davej:
Yes I agree with you that we may simply be akin to fish swimming around in a garden pond trying to figure out what's going on - but this argument can be used to refute everything! You can't successfully argue against metaphysics. For all we know we are sitting on the back of an infinite number of tortoises, one stacked beneath the other...

i never said we were akin to fish swimming around in a pond blah blah.. what the hell are you talking about? read my post again.

metaphysics? bleh?

Ivan

Originally posted by bonkey
OK...if all these things are true, then you are correct, but are phrasing your question in a very overcomplicated way. What you are effectively asking is :

"if the universe is actually deterministic, is it theoretically possible to determine it".

Obviously, the answer is yes.

However, if Heisenberg is correct, then the implications are weird and wonderful. You can never know the state you start from sufficiently accurately, and therefore cannot accurately model what will happen.

Does this mean that the universe is deterministic? Well, it doesnt actually say that it is or it isnt - and thats where the whole lovely can of worms comes in - because to date we have not found another way of answering that question. We can say that from our perspective the universe is non-deterministic, but that doesnt mean that it is.

jc

You know I just saw you reply to another post and I was thinking, omg when is bonkey going to reply to my post

And then you do, and then you phrase an answer in such a way I can accept it

And since I linked this thread to the other I might as well do vice versa. unless this is one of those things that is expressly forbidden in the policy and for breaking I could be banned from boards, in which case forget everything I just said.

Other Thread

Thank you for your reply Bonkey but what about the second part of Ivans "Stolen Unified Title Theorem"[Tm] assuming that the universe is deterministic wouldnt this lead to the existence of fate? Or what will be will be?

Suppose I go back in time to kill hitler, then the time line would already have taken this into account by the time the universe existed at the point where hitler was alive and he would have been killed by some computer weirdo from offaly and the timeline would continue on as if nothing was ever change.

In effect, fate would be proven?

Hobbes

Originally posted by Koopa
it doesnt mean you cant "know" the position and velocity of a particle (despite what some current-day physicists might say), by other means - eg. prediction by computer, etc.
for example, suppose you bounced a wave off a particle to "see" its position, but you knew EXACTLY how your wave would affect the particle - then you could know the current position and velocity of that particle, breaking heisenbergs uncertainty principle

I don't think it works like that.

You can't bounce the wave off the particle as you would have to know it's position and by knowing it's position you can't determine it's movement.

Also you wouldn't be able to know exactly how your wave would effect the particle as the particle would also effect the wave as the measuring device would also have to conform to quantum laws.

Or maybe I'm wrong?

Koopa

yes but my point was, how do you know there are no other ways to determine the position/velocity of a particle?
we cant be at that stage unless we already know everything about the universe, at which point you could say "there is no way to determine the position and velocity accurately"


[ignore this part of post unless youre bored]
i dont really want to get into a pedantic argument on what may or may not be possible since we dont have complete knowledge of everything about the universe, but ill start it off anyway.. (because im bored right now)
technically, if you took your particle to be the "reference point" of the universe, its position would always be "0" and its velocity would always be "0". there you go, you know the position and velocity of that particle with 100% accuracy, thus breaking heisenbergs uncertainty principle (although you wouldnt have a clue about the position and velocity of anything else in the universe)
[/ignore this part of post unless youre bored]

davej

what the hell are you talking about? read my post again.

Ok reading your post again:

you can think of a ripple in a pond caused by a stone being dropped into it, you can visualise it in three dimensions, but for something which could only observe the pond from one viewpoint directly above, you could write a set of equations that would hold true for the movement of each ripple that it sees (in the 2 dimensions it sees it in), it would still leave huge gaps in the 3d model of the ripples though, and thus definitely not be a complete description of the ripple (even in mathematical terms)

Now my analogy was that of a fish (eg carp) which is swimming in a pond in the bottom of a garden. They only see things in two dimensional terms and have no concept of a 3rd dimension. In fact this is a real example used by Professor Michio Kaku. I think it matches what you were describing quite accurately. (Except instead of a pebble disturbing the water, his example uses rain drops)

metaphysics? bleh?

A metaphysical argument is one which can't be disproved: because it is outside of "objective" experience. This also means that whatever someone asserts you can always reject it using metaphysics. No matter what physical laws we uncover about our universe, someone can always claim that we aren't seeing the big picture. Metaphorically speaking we could be living in a pond inside a pond inside a pond..ad infinitum.

quantum mechanics can assert whatever it wants, it doesnt mean it giving you the full picture.

I believe you rejected a qm assertion using a metaphysical argument, which is often the easy way out.

davej

DeVore

NGGGGGGGGGGGGGGHHHHHHHHHHHHH!!!!


Make the bad men STOPPPPP!!


Ok, since clearly fnck all of you read my link to THE ANSWER... I'll quote the relevant part here:

Originally posted by Stephen feckin' Hawking!

The German scientist Max Planck suggested in 1900 that light, X rays, and other waves could not be emitted at an arbitrary rate, but only in certain packets that he called quanta. Moreover, each quantum had a certain amount of energy that was greater the higher the frequency of the waves, so at a high enough frequency the emission of a single quantum would require more energy than was available. Thus the radiation at high frequencies would be reduced, and so the rate at which the body lost energy would be finite. <-- dead clever bit -- DeVore

The quantum hypothesis explained the observed rate of emission of radiation from hot bodies very well, but its implications for determinism were not realized until 1926, when another German scientist, Werner Heisenberg, formulated his famous uncertainty principle. In order to predict the future position and velocity of a particle, one has to be able to measure its present position and velocity accurately. The obvious way to do this is to shine light on the particle. Some of the waves of light will be scattered by the particle and this will indicate its position. However, one will not be able to determine the position of the particle more accurately than the distance between the wave crests of light, so one needs to use light of a short wavelength in order to measure the position of the particle precisely. <--- really important bit --DeVore (my emphasis)

Now, by Planck's quantum hypothesis, one cannot use an arbitrarily small amount of light; one has to use at least one quantum. This quantum will disturb the particle and change its velocity in a way that cannot be predicted. Moreover, the more accurately one measures the position, the shorter the wavelength of the light that one needs and hence the higher the energy of a single quantum. So the velocity of the particle will be disturbed by a larger amount. In other words, the more accurately you try to measure the position of the particle, the less accurately you can measure its speed, and vice versa. Heisenberg showed that the uncertainty in the position of the particle times the uncertainty in its velocity times the mass of the particle can never be smaller than a certain quantity, which is known as Planck's constant. Moreover, this limit does not depend on the way in which one tries to measure the position or velocity of the particle, or on the type of particle: Heisenberg's uncertainty principle is a fundamental, inescapable property of the world. <-- Death knell to Koopa's argument -- DeVore.

Now, unless Hawking, Heisenberg, Planck and a slew of other eminent physicists, a veritable TON of theories and a googolplex of experimental data can be explained in some other fashion then we have to accept this as truth.

btw: If you say "but suppose they are wrong" then we might as well all start supposing that everything is wrong and we can all live under the sea.

DeV.

Ivan

But their entired theories/explanations are based, as all good physics should be, on current scientific methods.

To say we may never discover a method is arrogant at best, ignorrant at worst.

Of course this stinks a whole lot like "How do we know there isnt a god, maybe we'll discover one day.... etc. etc."

I cant help it, I just feel it must be possible to detect velocity and speed in a particle without altering its velocity and/or speed.

Call me dumb, but thats how I feel.

DeVore

ok, thats your perogative just as long as you dont want it taught in schools under the name of "science"

All maths and science are based on fundamental assumptions (not many but they are clearly identified). If those assumptions are wrong (and they are REALLY basic) then all math/physics is wrong.

Considering that we are able to model from the super-micro to the super-macro with exact correlation, I'll stick to my science and you stick to your gut heheh...

DeV.

Koopa

Moreover, this limit does not depend on the way in which one tries to measure the position or velocity of the particle, or on the type of particle: Heisenberg's uncertainty principle is a fundamental, inescapable property of the world. <-- Death knell to Koopa's argument -- DeVore.

alright then. explain a wave (exact explanations only, something like 'what is the medium for a wave of light', not 'a wave is a disturbance in any medium, eg. water' - im looking for what the medium for a wave of light is (the answer i expect is 'we dont know, we havent found it yet, when we find it (and name it) ill let you know')).
explain a particle, for that matter (particle of what? its all theories here, our CURRENT knowledge doesnt extend much past sub-electronic particles).

if you dont know for sure exactly what these things are, then you would be wrong to say "there is no way to find out <x> about this particle", because you dont know that there isnt (you only know what you CAN do, not whats possible, in this situation)
davej - fair enough, i didnt realise the type of argument i was putting forward already had a label, but label or not, its wrong for someone at our level of knowledge right now to say "there is" or "there isnt" any other way to determine those two things about a particle..
technically, based on the odds of there NOT being any other way to measure the position and velocity of a particle knowing only how much we know about those two things, i would say that the odds vastly favour that "there is" a way to measure those things, just that we havent found them yet

saik

www.dictionary.com/search?q=wave
AHHAHAHAA.

Nevyn

well as complex and confusing as the secinctific way of looking at it well all that cne be done it theriose and as they ant prove that is all it looks likey to remain as just theories.

The whole thread looks like it should be in the science section not humanites

I guess I was expecting arguements about free will vs preordination of events or destinty or fate.
As in as we all have free will who can predict what we will do from moment to moment . Ok we are creatures of habit but that aside can we plot our own charts knowing that the free will of another make change it all.

Snowball

I think before answering the question Ivan posed you would have to answer the question of:

Is there such a thing as a totaly random event?

If there is not well then maybe with the right technology and the right minds it might be possible but what if there is, what if a totaly random and unpredictable event exists. What if there are some events, that under no curcumstances, are predictable because they have no pattern or disernable way of being predicted no matter what technology or great minds are bihind the attempted prediction.

So, is there. Is there such a thing as a totaly random event?

Koopa

i dont think there are truly random events, of course i could be wrong here - just that i think if there were truly random events happening in the universe, the laws of physics would break down fairly regularly as a side effect - "random" is "inconsistent" by definition, so if there is randomness in the universe (not randomness from people's perspectives, i mean real randomness) then the universe would be inconsistent


as for the 'free will' part, well from human perspectives we would have free will, just taking the pond analogy again, "if you cant see the whole pond, then events happening outside your field of vision would result in seeming "random" events happening on your side of the pond as well, even though theyre not really random - if you could see the whole pond to begin with, you could have predicted them" - as humans, we have free will the same way a computer playing chess does - to itself, it DOES have free will in every way to do whatever move it decides on, because it is defined by its chess-playing rules. there is only one way it can react to any given situation, but that is "free will" for it, because the rules it uses to decide what move to make are part of the definition of its "decision making capability"

oh, and "SAIK", is that "FH|SAIK", HMMM? it seems like the cat has been caught by the very person that was trying to catch him..
some useful links: http://dictionary.reference.com/search?q=butterfly , http://dictionary.reference.com/search?q=cup
and dont forget, when the lion growls, the bear will walk - when the baby eats, the mouse shall sleep, and last but not least, when the rabbit burrows, the hen shall have sex - think about it.

Koopa

not really related to this, but heres something for you to read if youre bored

http://www.cosmiverse.com/news/science/0303/science03190301.html

from article:

"These findings provide an opportunity to resolve details in an object smaller than a wavelength."

Devore:
However, one will not be able to determine the position of the particle more accurately than the distance between the wave crests of light, so one needs to use light of a short wavelength in order to measure the position of the particle precisely. <--- really important bit --DeVore (my emphasis)

Snowball

I was watching the X-files (for the first time in years) last night and I know thats its a bit... well u know but none the less the Char Daina Scully was asked about the universe and its predictablility and where there it was possible to predict someones presonality on the basis of their numerology (u know numerology, that thing there your name and dob make a number between 1-9 and then it defines ur personalitym, anyways) and she said (not a direct quote word for word because I've not that good a memory but it's close):

"No, no because I don't belive that something as complicated as the universe can be defined in a single calculation or formula"

Thats what I belive. How can something as complicated and diverse as the universe be explained and predicted in a mathematical calculation. I dont doubt that some of the things that happen in the universe can but all?

I mean look and things like me making up before the phone rings, or thinking of someone that you hav enot seen in a long time and then they ring you. Day-ya-vie (or how ever it's spelt). Or even in my case where I used to wake up if someone wanted to get into my room with bad intentions (sounds strange but i'll explain). Years ago when all my family were at home my mother (as all mother's do) used to just come into my room when I was asleep (as I always was) and bump cloths and so on but when my sis wanted to rob cd's or other gadgets of mine I would wake up even before she was in the room. My mother could just walk in and out but when my sis tried to sneek in it woke up. She had to drop some cloths off once and just walked in and I did not wake up but when she realised I was not awake she tried to take my walkman and I was awake in a flash.
I have heard of stranger things that can't be esily explained and definetly not entirly explained.

Koopa

where there it was possible to predict someones presonality on the basis of their numerology

whats this got to do with numerology?

How can something as complicated and diverse as the universe be explained and predicted

the same way something as complicated and diverse as your computer can be explained and predicted, if you know enough about it

Zukustious

This uncertainty princible doesn't mean "we" can't predict the future of whatever particle, it means that it cannot be predicted. Apparantly, every possible reality does happen. There are numerous paths a photon can take from one point to another. It takes them all. That's what the uncertainty princible is all about. Alternate realities are assumed to be in existence. Some evidence to go with this is that there are gravitational effects on certain galaxies, i.e. they're being pulled to some point. When the point is observed, there is nothing there.

It is thought that gravity is from other universes. Different quatum realities. They are being pulled by something and this is a possible explanation. Personally I found this really interesting.

Koopa

you're making statements but not offering any logic behind them..
example:

This uncertainty princible doesn't mean "we" can't predict the future of whatever particle, it means that it cannot be predicted.

says who? if it says that, then whats it based on? how do we know its right?

There are numerous paths a photon can take from one point to another. It takes them all

this is bull****, by the way.., its an old theory model which was used to explain the behaviour of photons going through a diffraction grating (i think - been a long time), and even then it didnt explain it perfectly

the stuff about alternate realities.. in fact, most of your post, is all theory. come back when you have some facts to back it up, for example the gravitational pull on the far away galaxies could be caused by almost anything, it could even be so-called "dark matter" which is basically matter which doesnt emit light or whatever (like an asteroid, as opposed to a star). plenty of explanations , would be incorrect to choose one arbitrarily until you have some facts to correlate with the theory

Zukustious

That's what's weird about quantum mechanics. It seems completely illogical.

The dark matter theory could be true, but it would take a hell of a lot of dark matter to create the gravity to pull those galaxies. You'd have to have galaxies of dark matter which would be huge and they would be detectable if a "normal matter" galaxy were to pass the space behind it.

Koopa

if quantum mechanics seems illogical, then id tend to think it wasnt giving the whole picture

rules can work "most of the time" (quantum mechanics works "most of the time") without giving the real picture. example: even if you didnt know anything about a robot/computer, you could still somewhat inaccurately predict its behaviour to something just by watching how it reacted to that thing previously, but if you knew everything there was to know about the robot/computer, you could predict its behaviour perfectly.

The dark matter theory could be true, but it would take a hell of a lot of dark matter to create the gravity to pull those galaxies

true, but its a theory - at this time given our knowledge its at least as valid as the one about "alternate realities"

remember, we're not even sure what gravity is right now - a lot of mass may not necessarily needed for a lot of gravity, in fact it could even be another, as yet unknown, force acting on those galaxies - we dont know.

in my opinion, both the uncertainty principle, and quantum mechanics, are "transitionary" physics - they work in certain situations, but not in others - because they dont present the full picture, and theyre mostly derived from observation/experiments (which cant paint a complete model) as opposed to actually theorising a complete model.
its kindof like how the greeks(?) used to think there were 4 elements - earth, fire, air, water - that made up everything.. it worked for them, a water element could dissolve an earth element, and so on - for them it was "true", for example it predicted the corrosion of seaside rocks by the sea, etc. - the only real reason we have a better model of the elements is because we've observed atoms, molecules, etc. - theres still huge gaps on our knowledge though, to a future generation our current physics will probably seem as primitive as the greeks's seems to us, if it has rules such as

This uncertainty princible doesn't mean "we" can't predict the future of whatever particle, it means that it cannot be predicted.

Ex_hale

interesting read lads!

just a few thoughts, dont read into em too deeply, im tired enough as it is:)

personally i believe future predictions of the the afforementioned type will and could never exist. everything in the universe may not be random, but it does respond to certain forces, mostly gravitational, whether those forces can be predicted will always be to a degree of 'the unknown' and would always be theorised since every ounce of moving matter exherts forces on another in the universe it would be literally f&ckng impossible to take all that into account when trying to accurately predict the path of one single entity in the whole scope of things considering for eg. the hiss of tv static to this day, denotes radiation remnants that still lingers from the big bang!
what began was a universe with no stars, no galaxies and no light, just a mix of primordial gasses (mainly hydrogen/helium and smaller quantities of lithium) immersed in invisible matter, to the infinite sea of galaxies we know about today.

"The most persuasive theory about the origin of galaxies depends on the behavior of particles no one has ever seen. Known only by its gravitational force, mysterious dark matter pulls ordinary matter into its web, amassing enough gas for galaxies to form. Ordinary matter accounts for only 10% of the universe; the rest is dark matter." hawking pronounced the discovery of dark matter as "the discovery of the century, if not of all time".

even after the big bang it is thought the universe plunged into darkness for another half billion years before something happened to bring it all together. i envision that the universe is still growing, still evolving, still changing, creating more gases, more elements and even worlds with more diversified life than our own and so forth hence anything that continues to grow is not necessarily predictable is it?. even if you used the big bang as your point of reference, you would have approx 15billion years of chaos and creation to analyze, a computer would go insane trying to figure that one out!

all in all, as the human race progresses, i think we are getting more and more, probably unconsciously, in tune to our surroundings and that of the future. who knows, one day we might not even need to figure it all out:) a girl i know once told me a story, she said her mother had a dream about her boss dying and falling into her arms, around that time (they had just moved from the area) she got a phone call telling her that he had died suddenly. im sure there are plenty of people who have heard stranger tales but thats what makes life interesting for us all isnt it? i for one would hate to live in a world of predictability.

Andyzzzzz

See, I've been thinking about this a bit too lately. I know about the Heisenberg uncertainty principle etc etc etc, but that's only really relevant when you start talking about measuring stuff (e.g. trying to build a future-predicting computer).

What I think, until someone comes up with a convincing argument to persuade me otherwise, is that regardless of whether you can know the position and momentum of all the particles, they do all have have a definite position and momentum. As such, when they collide, there'll be a definite outcome. Obviously you couldn't measure it (so no future-predicting machine), but I still thing that because it's happening it kind of implies a complete lack of free will. What happens happens.

That's what I think, convince me otherwise.

Meh

Originally posted by Zukustious
That's what's weird about quantum mechanics. It seems completely illogical.

Counter-intuitive, yes. Illogical, no.

Capt'n Midnight

..and even more on trying to change it - think of market research

I take it you have read Foundations - psychohistory or some such. Using demographics and psychology to determine trends.

I like the old Jesuit idea where they could mould children's minds - ie. predict the future by forming it..

Quantum effects prevent exact solutions - but you can get statistical averages - but then there is the problem of chaos - best way to solve this is social engineering - get people to rat on each other, that way you will have a nice stable dictatorship...

On the science forum I posted a number (factorial 10E340 or somesuch) representing all possible combinations of all possible universes the size and age of ours...

simu

I think free will is an illusion but, on the other hand, I don't see humans having the computational facilities to predict the future accurately anytime soon, if ever. I mean, even if you could overcome the uncertainty principle (and I'm not saying this is possible) you would need to make huge amounts of measurements and calculations and there would simply be too much data to tabulate to make any headway into predicting events at "our" level (i.e. our day to day world as opposed to predicting the movement of particles in a lab experiment).

But, just for fun, imagine what if would be like if you could sit down at a console and read all about what is going to happen to you/other ppl/the world in the next 5 minutes/next millenium, whatever.

I imagine the universe must maintain some sort of internal integrity i.e. the going back in time to kill your own grandfather paradox could not be realised as (apart from the trouble of inventing time-travel!) it would cause inconsistancy. So, even if you knew when you were going to die you could not prevent it from happening. You'd probably spend the afternoon at your console reading about all your attempts to avoid your unfortunate death caused by being crushed under a pile of cabbages rolling down a hill on May 3rd 2045 and then how this happened anyway. (Also assuming there would be a nice user-frinedly program that would translate all the data on this prediction computer to a more easily readable format). The universe would have "factored" in the effects of humans having developed the ability to predict future events, a bit like the plot of the film 12 Monkeys, I guess.

So, how would this affect people? I'm sure many would get depressed about it but as new generations grew up, future prediction would become banal and would be as obvious an idea as the earth being a sphere is to us. Going to find out the time of your death would be something people just get around to at some time or another, just like, say, losing one's virginity. Of course, there would probably be obscuritans who would reject this new technology just as these are those who reject evolution today. Possibly more worrying would be the issue of who has access to the data - the rich and powerful only? and the threat to privacy brought about by being able to predict people's thoughts.

Speculation is so much fun!

As for Donnie Darko, my interpretation of the film was that the universe was running in a patchy(well, more complicated than we imagine) manner, i.e. that determination worked in many different directions, not just straight ahead in time from the big bang, as we like to think of it. Like a drawing - you draw a picture of say, a city and after drawing say a sun in the sky, you decide you don't want it to be daytime so you erase the sun and put a moon or an airplane or whatever instead. Your sun would have existed for a while and then ceased to exist. I thought the film implied that the universe was constantly testing things out and modifying itself on all sides and that although we like to think of the past as being fixed, it is in fact also subject to change. Perhaps the universe will "decide" it no longer wants me in it and will go back and modify all aspects of itself relating to me. For some reason, in the film, it went wrong, as Donnie became aware of what was happening - the horror! He realises he is to the universe the equivalent of a page of an essay you consign to the bin!

If the above paragraph makes sense to you, please explain it to me:)!

popinfresh

Humans do have free will, but free will is predictable.. And also, is it not like physically impossible for a computer to emulate every single atom in the universe, after all, this computer would have to be physically larger than the universe when you consider the nature of computers.And also, the computer itself would have to predict itself, as it is also made of atoms and part of the universe. The only thing I can think of is to create a parallel universe to ours and then, if it's possible, manipulate the time to show that universe how you want it. Of course I'm guessing it'd be something like the year 2700, before something like that could even be comprehended, if it's even possible. We would have to find a way to extend our influence past our universe, which may by definition be impossible..

simu

Maybe our universe is just an emulator then:)

But, seriously, You couldn't even build a parallel universe to predict the future because the act of our observing it to see what happens would cause divergence with our own universe.

loismustdie

Originally posted by Snowball
Is the problem that Ivan is talking about not solvable by using multiple computers comunicating between each other? Then one could know the composition of the atom and the other could know the trogectory and speed. If they were fast enough could one not predict the future?

Oh but jst to shoot my self in the ass. Ivan, we were talking last week about decripting some encription algarithum (the prob is I cant remember the name of the encription) and the fact that it would be imposible because th computers needed would need more energy than it is possible to produce?

why bother postin up if you realised a mistake? lol
why wouldn't there be enough energy