First off, all that i am about to say is completely theoritical. It is impossible to do as I am about to say. I want no replies about how silly it is to ask this.
If some how we had the power to create an exact replica of this word at any point in time and having the same exact stimuli as the our earth at that point in time, would it have the exact things happen in time. I mean to the proton, every being on earth, and every rock in the same place. I also assume that if we did this exactly, everything would be alive if it were originally.
For example, If we recreated the world of 50 B.C. with the matter from this world, would it have the same industrial revolutions that led to today.
I am basically saying if it were possible to rewind fate, would fate continue in the same path.
I don’t think it’s silly to ask it, but I do think it’s silly to post it in General Questions, where we generally post questions that have a definite answer, like, “Why is my cat vomiting?” or “How should I care for my leather jacket?”
Well, it may end up in GD, but I think the intended General Question here is “is the universe deterministic?”
Of course we are a looooooong way from knowing the answer to that, if such an answer is attainable, but the current ideal is that quantum uncertainties mean that the universe is not, in fact, deterministic.
The slightly longer answer is no, not if Herr Heisenberg has anything to say about it.
The various activities at the subatomic level are, in many cases, truly random. In other words, given two exactly similar setups, you can’t expect identical outcomes. There is no way to predict exactly what happens. The best we can do is state the probabilities of each possible result.
So, you would not end up with the same world. At least not if you accept the assumption that the laws of physics are all that controls the actions of matter and energy (but if you don’t, you’ll be in GD right away).
Subatomic particles are random, in the sense that we can’t say exactly what they will do, but we can say what the probability is that they will do something. IANAPhysicist, but in the current model we’re using, the uncertainty is right there - right at the lowest level. The Uncertainty Principle is pretty damn inviolable.
To take the next step to macroscopic changes, radiation from Earthbound radioactive materials can cause mutations. All you need is one extra mutation to happen, or one that did happen to not happen, and you’ve got a slightly different person. A slightly different person will react slightly differently, causing all the people around him to have slightly different experiences. Once these differences are large enough that a different sperm fertilizes an egg, you have a completely different person born. Maybe a boy instead of a girl, or vice-versa. These differences are enough to affect everyone nearby, and soon, just about everyone born is a different person.
I’d give it maybe 150 years, tops, after you copy the Earth, before you have a completely different human population.
By exact I meant to the n’th degree. down to the subatomic particles. I hope when you say radiation from extraterrestrial sources, thats not a stimuli is that?(being sarcastic) because I did say all stimuli were the same. Oh and even if subatomic particles movements were random…uh we are getting off topic. I beleive not one of you have seen the point. If it were exact, and (humor me) subatomic particles did not move randomly, would the world turn out the same.
I really want to know where that guess came from. There has never been a population changed it terms of evolution in a mere 150 years. But you are right if things weren’t exact, it would not be exact, thats basically what you are saying.
Not to put too fine a point on it, but if you want to change the laws of physics, you can get any answer you want. If you take away the Uncertainty Principle, I suppose you would get a completely deterministic world. If you had the power to make your copy exact to that precision, you would not only be able to say that it would evolve and progress exactly as the world you copied from, but you’d be able to predict it’s state at any future time whatsoever.
However, if you want to confine yourself to the laws of nature as they now stand, you can’t do this. The randomness is true, so there is no way to predict future events in the subatomic world. Some of this unpredictability would affect macroscopic events, so the future cannot be predicted from the current state of all matter.
Due to the fact that an electron is not at a definite point, but has the possibility of being at various points at any one time, there are an infinite number of universes and the infinity of them is increasing exponentially all the time. So if you start at any time in our history and duplicate the world or universe, there will immediately be numerous amount of possibilities of the future course of the world, one of which we are here and now witnessing.
However, there exist many others that we cannot witness because they are beyond our universe. So, even now, as I type, many different events that are possible due to the uncertainty of the electron’s position and quantum mechanics in general other than the one I am witnessing, are occuring, but I can’t see them because they are spinning off in different universes.
And if you believe that crock, you’re as crazy as I am.
I’m not talking evolution, I’m talking different individuals. Once you have a different sperm fertilize the egg, you have a different person born nine months later. Even one different person will affect everyone they grow up with. The human gene pool won’t have changed, but eventually all the individual people will be different people.
Most of the 150 years is just that, even in ancient times, a few people could live to be 100 or so. Then I tacked on some time to allow for terrestrial radiation to alter some gene in an egg or a sperm that fertilizes an egg. The point isn’t to cause evolution, just to have a macroscopic entity (i.e. the resulting person) who is slightly different, and will then act slightly diferently, causing those around him to act slightly differently also, until these differences are great enough that a different sperm fertilizes the egg of some woman about to become pregnant.
Given all of the information it is even theoretically possible to obtain about a subatomic particle, it is not possible to produce a replica which will evolve in exactly the same way. It is conceivable, however, that there is information about a particle which cannot possibly be measured. In this case, the Universe might be deterministic, but we would have no way of proving it.
How are you creating your replica? Are you just making the most detailed measurements allowed by the laws of physics, and then setting something up so that all of those measurements match? Or is this some sort of magical process of duplication, which copies all of the “hidden” variables along with the measureable ones, but then lets the world run its course? If it’s the first option, then no, the result will not look the same. If you mean the second, then there’s no way to know the answer to the question, and you’re into philosophy and Great Debates.
Chronos, what’s the status on hidden variables? I thought some experiments based on Bell’s inequality had been performed, and the results agreed with quantum mechanics, and ruled out hidden variables. Any update on this?
Sorry, ZenBeam, I haven’t heard anything about such experiments… If anyone has any more information on them, please let me know. I’m not sure how one could go about ruling out hidden variables, and they’re not inconsistent with QM, only with one particular interpretation of it (the Copenhagen interpretation).
Until I see some experimental results, I’m standing by my answer.
