Is the future inevitable?

Given that there is chaos and randomness in both universes, they would gradually go out of synch. But Usain Bolt is still likely to win the 100m in both universes. A better question would be 'would the weather be identical in 6 month's time.'

If both universes contain randomness - as ours does - then systems like the weather that are regarded as chaotic won't keep in synch. The further away from the start postion you get the more difference there will be between the two systems.

A sporting event that starts identically and lasts a few seconds is unlikely to be effected by minute changes.

Someone will probably pop up and say that one fundamental particle or somesuch is identical to another, but until they do I'll say that there's no such thing as an identical anything is there?

For two universes to be identical over time, they would have to be totally deterministic - no possibility of chance, ruling out a universe like our own.

You're welcome ;-)

Caffeiene & Dr A

I understand the concept of chaos - at least in words - that's why I was careful to include both chaos and randomness into the game.

A system like ours that has both chaos and randomness would inevitably spin out of sync.

Im still trying to wrap my mind around the concept of determinism versus random probability. I dont think I believe in an either/or throw of the dice. I believe that the throw has been determined by a hypothetical observer.

You know the seeds of sychamore trees have little wings on them? They allow the tree to spread its seeds a distance from the mother tree. They get dispersed by the wind sometimes for hundreds of yards. Some of them land in roof gutters, car parks and roads, some get eaten by squirrels, some of them drown in lakes. Some of them get carried down river miles away from the tree.

Do you believe that where each individual seed lands has been preditermined?

Or do you think it more likely that that can not be true given the enormous number of variables involved - almost all of which are random and/or chaotic.

Phat writes: only if any one variable is no more or less influential than any other variable.

Eh?

Phat writes: Do we have a reasonable case that all variables have an equal influence?

This makes no sense Phat. All variables cannot have equal influence - a force 10 gale has more effect than a squirrel, but what has that got to do with anything?

The question I asked you was do you think that where a sycamore seed lands is predetermined?

If no, then you have your answer.

If yes, my next questions are how and why? (And you realise that if the seed's landing point is pre-determined and therefore unchangeable, your concept of free will is defunct.)

Phat writes: Well, I go by my slogan---I think that chance has no power to change anything....

What's the point of a slogan - especially one that's just plain wrong?

thus I believe God did it all and that all is pre-determined.

You believe in god because you have a slogan?

So yes, I'll give up my illusion of free will for the moment.

Yikes, are you sure? That destroys the whole concept of sin.

Now, however, I'm stuck with trying to explain how God has to micromanage every detail of every variable in order to create

Well that's the easy bit - he can do anything, no problem. That's the point of a god.

Sure. But the fact that there are billions of variables which all interact just demonstrates how rediculous the concept of pre-determinism is.

Caffeine writes: How? If you mean it makes prediction difficult, then no argument,

Substitute difficult with impossible and I agree. (re. sycamore seed dispersal)

but it has no bearing whatsoever on whether or not the universe is deterministic, as you just agreed.

Well obviously I agree. But it does rather point to the scale of the problem.

It may be simpler just to say that if there is any element of probability involved, then it can not be a deterministic system.

PT writes: Probability only refers to our ability to predict an outcome. That we see the universe as a set of probabilities has no impact on the fact that matter behaves in a perfectly deterministic manner. The only way that it is not a deterministic system is if matter does not behave in a consistent manner. Unpredictable does equal undetermined.

If we're not careful, this will decend into war of definitions.

The original question was if two universes came into being in identical states, would they remain synchronised (I'm paraphrasing.)

The answer is that if the universes are like ours - probabalistic - then they will go out of synch.

PT writes: The answer is that if the universes were identical then they would not go out of synch.

That's not the case. If there is probablility in the systems, they will inevitabley lose sync.

I could choose to do something or not on the toss of a coin - there would then be a 50% chance of the two worlds differing. If I do it 1,000,000 times it's a certainty that they will (unless you feel the need to be pedantic about it there still being an infinitesimally low probability that they will not.)

The other answer is that it is impossible to actually have 2 things that are absolutely identical because if you did then they would be the same thing.

Eh? It's already been said that electrons are identical. Is there only one of them then?

Edited by Tangle, : No reason given.

PT writes: If you flip a coin and it is heads and then you flip the coin in exactly the same way again it will also be heads because you did it the same way. Identical is identical. Don't you think that we could get a machine to always flip heads?

Then all you've done is predetermined the worlds by definition. That isn't the question. If you eliminate all possibility of randomness in both universes, then of course everything pans out the same. That was made clear right at the beginning. You've just defined it away - It's hardly a puzzle worth proposing.

And of course, if I flip a coin in an absolutely identical way in both universes then there is no free will.

pt writes: I don't think that randomness and determinism are mutually exclusive.

I do.

The results from the lottery ball machine are totally random and totally subject to the laws of cause and effect. We say that the results are random but any sufficient intelligence could theoretically predict the results. Randomness refers to our ability to predict.

Randomness means that the output can not be know except as a probability. If you re-define random as knowable with enough information and brain power that simply applies determinism.

When we create an AI that behaves in a manner indistinguishable from the average human, will it have the quality of free will?

Yes. No. It depends. We don't even know whether people have free will, let alone machines, or even - outside a daft religious idea - whether the term has any meaning. If it does exist at all, it's bounded. One thing is for sure though, if our world is deterministic, then whatever freewill is, we haven't got it.