Can quantum unpredictability prevent accurate future prediction?

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This is a bit speculative and without sources, so that's why ill chuck it here for some 'light debate'.



Could it be that the unpredictability of the quantum world occur to negate any possibility of accurate future prediction? I'm under the assumption that there is something fundamentally wrong with the notion of predicting ones future since the process itself would destroy itself.












Yeah don't kill me for crackpottery ;/
 

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The future is predictable to a certain degree, due to causal relationships. For example, if I drop an egg I'm fairly sure that I'll be cleaning the floor soon.
Absolute predictability is impossible. Back when I was reading up on this kind of stuff some 35 years ago, the term used for it was 'superdeterminism'. It's a no-no by QM. One nasty effect of it would be that we have no free will whatsoever. Everything would have to follow a script like clockwork. (And even that is a bad example, since I've had more than a couple of clocks go south on me.)
 
Blenton said:
I'm under the assumption that there is something fundamentally wrong with the notion of predicting ones future since the process itself would destroy itself.

What does that mean: "the process itself would destroy itself"?
 
Yes I agree that the future is predictable to a point, since the human race is one of the few animals to plan. But why are some things predictable? It seems almost as if the larger the object is, the more predicable it is (such as planetary movements).

Is it possible that the reason why we can predict the movements of these objects is that their ability to affect our future is somehow less than those of the smallest atoms?I guess it is safe to say we don't have any 'free will' to an outside observer. I don't think its nasty since only those higher up have the ability to see the gears turn. (Also what's with the term 'go south'? Not quite an expression used in Australia).
 
Danger said:
The future is predictable to a certain degree, due to causal relationships. For example, if I drop an egg I'm fairly sure that I'll be cleaning the floor soon.

However as you are distracted by a phone call, the dog rushes over -being fond of eggs- and cleans the floor for you.

However the sudden earthquake makes you run and eventually there is no more floor to clean.

However when looking for a cleaning cloth, you trip over the yoke, break a leg and you'd be rushed to the hospital. Some friendly paramedic cleans the floor.
 
Danger said:
One nasty effect of it would be that we have no free will whatsoever. Everything would have to follow a script like clockwork.
Technically we always have free will. I can go outside right now and will myself to fly through the air like superman. It won't work, but I can will it.
 
Blenton said:
(Also what's with the term 'go south'? Not quite an expression used in Australia).

:smile:
Yeah, I guess that there isn't much 'south' from there. Does 'go sideways' work for you? As in malfunction in a large manner?

edit: Andre, you have made the specific point that I was aiming for. That's why I said that I'd be fairly sure about cleaning the floor. Zoob, you still have that choice of whether or not to go outside. After that, it's up to gravity. (And remember next time to close your 'quote' function... :-p)
 
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What does that mean: "the process itself would destroy itself"?

I wasn't sure quite how to phrase it, knowing your own future would change that future and you'll end up dividing by zero...

Yeah, I guess that there isn't much 'south' from there. Does 'go sideways' work for you? As in malfunction in a large manner?

Is it a reference to American 'Southerners'? Could use the same term to describe those from South Australia :P
 
Science would hope that predicting the future (with reasonable accuracy) is possible. Of course, many of us are just interested in how the universe works. But if there's a way it consistently works, through cause and effect, then it must also be predictable to the extent to which we understand the nature of the cause/effect relationship.

So predictability is a necessity for any scientific theory.
 
Blenton said:
Is it a reference to American 'Southerners'?

I really don't know the origin. It might be a strictly Canadian saying, although I think that I've heard it used on Yank TV shows a couple of times.
 
Blenton said:
I wasn't sure quite how to phrase it, knowing your own future would change that future and you'll end up dividing by zero...
Hm...no. Knowing the future wouldn't automatically change the future.
 
Blenton said:
I wasn't sure quite how to phrase it, knowing your own future would change that future and you'll end up dividing by zero...
Uh oh! Now you're going to have to explain the "dividing by zero" part!

Is it a reference to American 'Southerners'? Could use the same term to describe those from South Australia :P
It is an idiom used to indicate that something has lost value or reliability. Our standard conventions for direction associate 'north' with upwards and 'south' with downwards (we - sort of ironically, though perhaps not being intentionally ironic - refer to maps with South America above North America as "upside down" maps). If the value of a stock "went south", that means it's price went down (think graphically).
 
Danger said:
The future is predictable to a certain degree, due to causal relationships. For example, if I drop an egg I'm fairly sure that I'll be cleaning the floor soon.
Absolute predictability is impossible. Back when I was reading up on this kind of stuff some 35 years ago, the term used for it was 'superdeterminism'. It's a no-no by QM. One nasty effect of it would be that we have no free will whatsoever. Everything would have to follow a script like clockwork. (And even that is a bad example, since I've had more than a couple of clocks go south on me.)

I don't personally agree that determinism implies no free will. Even if there is only one future, if the only way to determine its path accurately is to experience it, then that does not in any way limit the scope of free will, which describes the same future but using a different approach.

Even if you want to bring in unscientific concepts like "mind" or "soul", if the future is deterministic but unknowable, then you haven't restricted the freedom to choose.
 
Hm...no. Knowing the future wouldn't automatically change the future.

So you predict that you will meet your friend john tomorrow at his house. Don't go to his house under any circumstance. I can't see any reason why you would be 'forced' into your prediction, there is no destiny BS. Its all cause and effect. If you know the effect you can change the cause...

Just like Morpheus said "there's a difference between knowing the path and walking it"
Uh oh! Now you're going to have to explain the "dividing by zero" part!

Was just using dividing by zero as one of those end of the world expressions (Since looking into ones future would be the same as going back in time and killing yourself - who knows what would happen if it were possible).
 
Our ability to predict the future depends largely on how little detail is involved. Predicting what you'll actually have for breakfast is easy compared to predicting where every ship in the harbor will be. I suppose that future prediction is a skill and like any skill you can probably get better at it with practice. So that means that by the time I am 90 I will already know what my life is going to be like when I am 115.
 
As I understand it, according to the rules of quantum physics, you can set up two systems in the same state, but you can't be sure that they will both be in the same state at a later time. I don't know the standard definition of determinism. But by the way I use that word, either determinism is out, or quantum physics is the limiting case of a deeper theory. I would like to predict the latter, but this may not be a good time to do it.
 
It is possible to predict future but that is time intensive task such that predicting future in 1 year would take exactly 1 year/

But realistically, if you know what's in the mind of each individual, you can turn future to some degree (you make future not observe) in your favor by taking actions advantageous to yourself. But it is psychology but not quantum.
 
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We can't even predict the outcome of simplest cellular automata, in which cells grow according to extremely simple rules. The only way to find the outcome of cellular automata is to run the program.

And since behavior that behaves exactly like automata is found in nature everywhere, the only way to know the future is run its course and see what happens.
 
Blenton said:
So you predict that you will meet your friend john tomorrow at his house. Don't go to his house under any circumstance. I can't see any reason why you would be 'forced' into your prediction, there is no destiny BS. Its all cause and effect. If you know the effect you can change the cause...

The possibility of deliberately trying to change the predicted outcome is different than the proposition that knowing the outcome automatically changes it. The latter is a kind of Heisenberg effect: measuring the phenomenon automatically changes the phenomenon. The former proposes that unless you do something to change the outcome, it will happen exactly as predicted.

The third possibility is that the future is written in stone and will happen whether you know the outcome or not. In this scenario, your knowing the future was part of the script all along. Any effort you make to change the outcome only serves to ensure its happening, and those efforts to change it were always part of the scenario anyway.
 
It is possible to predict future but that is time intensive task such that predicting future in 1 year would take exactly 1 year/

Hmm I've briefly thought about this, that perhaps a computer could simulate faster than reality runs at. I don't know what to make of it, computers are still bound by the physical laws that they are trying to 'speed up'.
 
If MWI is correct, any prediction of the future has to be probabilistic. For many questions, the answer will be essentially unique (all alternatives adding up to <1%), for others, there may be variance. There is no absolute certainty. If you drop an egg, there's a 99% chance that you'll have to clean it up, and there's a 1% chance that something else will happen that will keep you from cleaning it (maybe you have a heart attack?). And there's always a 10^-30% chance that the egg will quantum tunnel through the floor and end up in your basement, and a number of possible outcomes (also adding up to an astronomically tiny number) where the question no longer makes sense, because a series of quantum fluctuations mean that the entity called "you" is no longer uniquely identifiable.

In addition to predicting the future, there's an issue of predicting the past. If you haven't heard anything about your 80 year old great-aunt for the last five years, there's maybe a 25% probability that she's already dead but no one bothered to tell you, and a 75% probability that she's still alive. You can't know which until you do the experiment. At that point, the "aunt-unknowing you" will branch into two you's with different amplitudes and different memories. This is not substantially different from the situation "you" were in 5 years ago. The only difference is that 5 years ago answering the question "is my great-aunt still alive on 3/14/2010" would've meant predicting the future, but today it means predicting the past.

The question can be posited even wider than that. If you possesses enough computational power and you have enough initial data to compute the probability for your 75-year-old great-aunt to live to the age of 80, you can compute probabilities of different outcomes for yourself, starting with your birth as the initial branching point. It would be extremely educational for you to learn, for example, that, in 10% of universes, you're dead along with your whole family and everyone you knew because of a nuclear war, or that there is a sizable probability for you to having died or having been paralyzed from the waist down in a motorcycle accident (if you ride a motorcycle).
 
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hamster143 said:
In addition to predicting the future, there's an issue of predicting the past. If you haven't heard anything about your 80 year old great-aunt for the last five years, there's maybe a 25% probability that she's already dead but no one bothered to tell you, and a 75% probability that she's still alive. You can't know which until you do the experiment. At that point, the "aunt-unknowing you" will branch into two you's with different amplitudes and different memories. This is not substantially different from the situation "you" were in 5 years ago. The only difference is that 5 years ago answering the question "is my great-aunt still alive on 3/14/2010" would've meant predicting the future, but today it means predicting the past.

Where do you get the 25-75% odds, and what exactly is the experiment that determines if she's still alive or not?
 
zoobyshoe said:
Where do you get the 25-75% odds, and what exactly is the experiment that determines if she's still alive or not?

25-75 is just an estimate. 2005 SSA death tables put overall 5-year survival rates for 75-year-old females in the United States at 83%.

The experiment that determines if she's still alive involves calling her or someone who'd know that, and asking. It's essentially an inverted version of Schrödinger's cat.
 
hamster143 said:
25-75 is just an estimate. 2005 SSA death tables put overall 5-year survival rates for 75-year-old females in the United States at 83%.

The experiment that determines if she's still alive involves calling her or someone who'd know that, and asking. It's essentially an inverted version of Schrödinger's cat.
OK, that's more or less what I figured, and in your saying a prediction has to be probabilistic I would say, then, it is no longer really a prediction, merely an estimate of probability, which is a lot softer. A semantic quibble.
 
zoobyshoe said:
OK, that's more or less what I figured, and in your saying a prediction has to be probabilistic I would say, then, it is no longer really a prediction, merely an estimate of probability, which is a lot softer. A semantic quibble.

In some sense, in MWI there's no such thing as prediction, because anything is possible as long as it does not violate some conservation law.

But the nice thing about quantum mechanics is that, even though anything is possible, the vast majority of outcomes are incredibly improbable. The probable outcomes are the ones that appear classical on the face of it (an egg falling down on the floor and breaking - classical & likely, an egg falling through the floor - possible but very unlikely).

Sometimes quantum events can lead to macroscopic bifurcations of paths and then you get multiple likely outcomes. There's even an iphone app for that:

http://itunes.apple.com/us/app/universe-splitter/id329233299?mt=8
 
MWI = Multi-World something, right?
 
Blenton said:
Could it be that the unpredictability of the quantum world occur to negate any possibility of accurate future prediction? I'm under the assumption that there is something fundamentally wrong with the notion of predicting ones future since the process itself would destroy itself.
I just reread this and realized I hadn't read it properly the first time.

You are proposing that quantum unpredictability is a built in security measure of sorts (The Firewall of the Universe?) designed to prevent accurate prediction since ( you assume) accurate prediction would automatically change the future. Quanta, with gremlin-like berzerker tactics, refuse to behave deterministically, but they do so in the service of an ultimately deterministic cause.

In other words, you are proposing that the future is, in fact, written in stone and quantum unpredictability protects the stone's scenario from being read before it happens.

You are proposing the madness of electrons is like the madness of Hamlet: there's method in it.

It smacks of Intelligent Design (it's specifically aimed at foiling human curiosity), but it might make a good springboard for the plot of a Science Fiction novel, say, The Blenton Code.
 
Haha, well that's pretty much what I was suggesting. I don't think its any 'intelligent' deliberate action but rather some physical law that exists in order to prevent the chaos that would ensue without it. There has to be a reason for the madness of electrons, and I've not read anything explaining why it occurs, just how.

I still firmly believe that seeing ones future would change it. You propose that you seeing your future is merely part of your future to begin with but that 'future' you vision would not be real at all since it could never be achieved with you knowing the variables.
I'd very much like to see a The Blenton Code :D
 
Blenton said:
Haha, well that's pretty much what I was suggesting.
OK. Sorry I gave that a sloppy reading first time around and missed your point.
I don't think its any 'intelligent' deliberate action but rather some physical law that exists in order to prevent the chaos that would ensue without it. There has to be a reason for the madness of electrons, and I've not read anything explaining why it occurs, just how.
If you're not proposing an Intelligent Design argument it becomes hard to account for any proposed "protective physical law. (Not even conservation laws are "protective"; they're just neutral book keeping.) We don't find things behaving protectively until we get into biology, which is where we also start getting into the possibility of things predicting their future, but that's very late in the game. Quanta must have been behaving non-deterministically since, at least, the big bang. They wouldn't have suddenly adopted that behavior at the dawn of human consciousness (or wherever you want to place a bio-ability to predict the future.)

I still firmly believe that seeing ones future would change it. You propose that you seeing your future is merely part of your future to begin with but that 'future' you vision would not be real at all since it could never be achieved with you knowing the variables.

You've seen a movie, right? The second time you watch that DVD you know that movie is going to play out exactly as it did the first time you watched it. The fact you know the plot ahead of time does not change the future and turn it into a different movie.