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Does quantum theory imply the universe is preordained?

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Re: Does quantum theory imply the universe is preordained?

#2
When I was a teenager I had an idea:

If you rolled marbles down a hill, assuming that identical starting conditions were applied each time, then the marbles' paths and final position would be the same each time.

This also implies that if you know the starting conditions, you could calculate the state of any point in time from there.

It made me curious whether you could apply this same logic to our universe -- though I get the feeling it's not quite as simple a system as marbles on a hill.

Re: Does quantum theory imply the universe is preordained?

#3
post #2

When I was a teenager I had an idea: If you rolled marbles down a hill, assuming that identical starting conditions were applied each time, then the marbles' paths and final position would be the same each time. This also implies that if you know the starting conditions, you could calculate the state of any point in time from there. It made me curious whether you could apply this same logic to our universe -- though…

The fundamental question here is whether or not you can get identical conditions in the first place. If for example spacetime is quantized, then it might be that the basic unit of our reality displays the sort of quantum behavior that makes it so hard to predict outcomes. It wouldn't just be a complex system, it would be an essentially random and ever-changing system. By the same token it could be the opposite, maybe it's just a really complex system as you were speculating about, and while nothing is random, it's essentially impossible to predict.

In essence, is this a universe where a version of Maxwell's Daemon could conceivably exist, or is it a universe that even a god-like being would find random?

https://en.wikipedia.org/wiki/Maxwell%27s_demon

Re: Does quantum theory imply the universe is preordained?

#4
post #2

When I was a teenager I had an idea: If you rolled marbles down a hill, assuming that identical starting conditions were applied each time, then the marbles' paths and final position would be the same each time. This also implies that if you know the starting conditions, you could calculate the state of any point in time from there. It made me curious whether you could apply this same logic to our universe -- though…

i think for physical systems this might hold true in some way, though, i am not a physics person at all. it just 'feels' that way to me. however, life is also there, and life doesnt nessesarily follow such rules, as actually most of (intelligent?) life is not physical. (emotions, thought etc.) but does have impact / effect on the physical. i dont think non physical things are so determenistic. (maybe they are, but it doesnt 'feel' that way to me)

Re: Does quantum theory imply the universe is preordained?

#5
This does make me wonder: how do we know that random quantum processes are truly random?

This gets philosophical very quickly. But for our purposes: independent, uniform, etc. But how do we know there isn't another (earlier) way to observe the result in some fashion.

Re: Does quantum theory imply the universe is preordained?

#6
I think, ultimately, there are only 3 possible explanations for the paradoxes of the quantum world. 1) superdeterminism (everything including our choices in quantum experiments today were fully determined at the instant of the Big Bang), 2) something "outside" our observable reality acting as a global hidden variable (whether something like the bulk in brane cosmology or whatever is running the simulation in simulation theory) or 3) emergent spacetime (if space and time are emergent phenomena then locality and causation are not fundamental).

Re: Does quantum theory imply the universe is preordained?

#7
post #2

When I was a teenager I had an idea: If you rolled marbles down a hill, assuming that identical starting conditions were applied each time, then the marbles' paths and final position would be the same each time. This also implies that if you know the starting conditions, you could calculate the state of any point in time from there. It made me curious whether you could apply this same logic to our universe -- though…

There's a good documentary called "The Secret Life of Chaos" that has a fairly cool overview of this concept.

Though it's just the beginning of a very deep rabbit hole, possibly unending.

Here is a link: https://www.dailymotion.com/video/xv1j0n

Re: Does quantum theory imply the universe is preordained?

#8
post #4
post #2

When I was a teenager I had an idea: If you rolled marbles down a hill, assuming that identical starting conditions were applied each time, then the marbles' paths and final position would be the same each time. This also implies that if you know the starting conditions, you could calculate the state of any point in time from there. It made me curious whether you could apply this same logic to our universe -- though…

i think for physical systems this might hold true in some way, though, i am not a physics person at all. it just 'feels' that way to me. however, life is also there, and life doesnt nessesarily follow such rules, as actually most of (intelligent?) life is not physical. (emotions, thought etc.) but does have impact / effect on the physical. i dont think non physical things are so determenistic. (maybe they are, but it…

What makes you say that life is not physical?

There seems to be no reason to believe that it's not.

On the contrary it seems most plausible that everything, including emotions, thoughts, decisions, are just chemical and electrophysical reactions. Thus deterministic.

Re: Does quantum theory imply the universe is preordained?

#9
post #7
post #2

When I was a teenager I had an idea: If you rolled marbles down a hill, assuming that identical starting conditions were applied each time, then the marbles' paths and final position would be the same each time. This also implies that if you know the starting conditions, you could calculate the state of any point in time from there. It made me curious whether you could apply this same logic to our universe -- though…

There's a good documentary called "The Secret Life of Chaos" that has a fairly cool overview of this concept. Though it's just the beginning of a very deep rabbit hole, possibly unending. Here is a link: https://www.dailymotion.com/video/xv1j0n

There's also a decent (not documentary) limited series that explores the idea of determinism. It's pretty good and may be of interest. https://en.wikipedia.org/wiki/Devs_(TV_series)
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