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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?

#51

Post by Lichtso »

PheonixPharts wrote: post #15

"Random" is a property of your mind, not of the world. If I shuffle a deck of cards in a way that you don't know about, then the next card I pull is "random" to you even though, obviously, if one were to turn the cards face up nothing would have changed about the order of the cards, but now the next card would be fully deterministic. I could likewise sort the deck with an algorithm completely unknown to you. I could…

The uncertainty principle is just a really misunderstood concept because it was first discovered in the context of quantum physics (Heisenberg 1927) and only later (Gabor 1946) the underlying mathematical principle that causes it was discovered.

It has nothing to do with measurement, knowledge, randomness or even our physical reality at all. It is a much more fundamental mathematical phenomenon [0] that always occurs when you switch representation between time and frequency domains and it tells you how you can arrange information in such mixed representations.

[0]: https://en.wikipedia.org/wiki/Uncertainty_principle#Signal_p...

Re: Does quantum theory imply the universe is preordained?

#52

Post by nyssos »

simiones wrote: post #49
nyssos wrote: post #36

Earlier quoted context omitted.

> Why would belief that we are just agents responding predictably to stimuli imply that one would not respond predictably to stimuli? This is determinism, not superdeterminism. Superdeterminism claims that the state of any system you measure is always already correlated with the measurements you perform on it: photons emitted a billion years ago encode information about where someone is going to choose to point a tel…

Sure, but superdeterminism implies determinism. That is, if the world is superdeterministic, it is certainly deterministic, so living agents definitely react to stimuli in a theoretically predictable manner. Interestingly, it's actually very hard to define what it would mean to believe in determinism, but not superdeterminism. Ultimately if the universe is deterministic, that must mean that everything that happens is…

> Ultimately if the universe is deterministic, that must mean that everything that happens is predictable from the initial conditions of the universe.

This is still not superdeterminism. The superdeterminist claim is a statistical one: your choice of measurement is not even approximately conditionally independent of the state of the thing you're measuring. Ever. There are plenty of deterministic processes that nonetheless wipe out most correlations over the long-term: thoroughly mixing two fluids will do it. Preserving a strong correlation between the future state of your brain and the exact luminosity of a star a billion light years away at one particular moment, over the whole history of the universe is incomprehensibly unlikely. And superdeterminists claim that this happens every single time.

Re: Does quantum theory imply the universe is preordained?

#53

Post by digging »

simiones wrote: post #40
digging wrote: post #30

Earlier quoted context omitted.

Not sure I agree fully in the case of Uncertainty. To the best of our knowledge, an undetermined quantum property is actually undefined. Whether we go with the simple Many Worlds or the Copenhagen wave function collapse or even Pilot Wave theory, when the value becomes defined it is randomly selected (or our World is a random selection of all of them) according to the wave function. I believe what you're saying is th…

I don't think you're right about the many worlds interpretation here. In the most popular "simple" many worlds interpretation, the whole universe is a QM system described by the universal wavefunction. The "worlds" are just "branches" of the wavefunction that are not entangled with one another. The Schrodinger equation (and the more advanced QFT versions) are fully deterministic differential equations: the state of t…

Hm, that could be correct actually. Perhaps Many Worlds is the most deterministic interpretation and I've got it backward - this clearly is not my day job :)

Re: Does quantum theory imply the universe is preordained?

#54

Post by tromp »

> All the observed complexities can be regarded as partial descriptions of a simple fundamental reality: the Universe’s wavefunction. As an analogy, a perfect sphere can be cut into many chunks with complicated shapes, yet they can be put back together to form a simple sphere.

As another analogy, the 100-bit lambda calculus term

(λ 1 1) (λ (λ λ λ 1 (2 (λ λ λ 3 1 (2 (λ 2)))) (3 (λ 4 (λ 4 (2 1))))) (1 1)) (λ 1)

is a binary tree containing all (infinitely many) closed lambda terms at its leaves. Thus including representations of all possible data and all programs.

Re: Does quantum theory imply the universe is preordained?

#57

Post by Pet_Ant »

voxl wrote: post #14
digging wrote: post #12

Earlier quoted context omitted.

A good quip, lol. But of course they would, because they must, because the feeling of control (that is: the unconscious belief in control) is just as intrinsic as the actual absence of control.

which in other words makes superdeterminism unfalsifiable, because any attempt to do so can be met with "it must have been that way"

Don't know why this was downvoted. Superdetermination is indeed unfalsifiable, because the "super" part means that there does not exist anything that has been not determined, including our thoughts, this comment and someone rolling their eyes reading this.

Being unfalsifiable doesn't mean it's not true, just that it isn't a scientific theory.

Re: Does quantum theory imply the universe is preordained?

#58

Post by mensetmanusman »

gavinray wrote: 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…

They would be the same until some number of zeros, past which, Heisenberg uncertainty takes over and you cannot predict.

Re: Does quantum theory imply the universe is preordained?

#59

Post by mensetmanusman »

digging wrote: post #11
sim7c00 wrote: post #4

Earlier quoted context omitted.

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…

For classical physics it's basically true[1]; see Laplace's demon. I recall also independently inventing determinism as a kid after I realized how easily I'd been swayed by external factors into buying one toy over another. For non-physical things, such as emotions and thought... well, we have no actual proof they're anything but physical. We just don't have proof that they're entirely physical, either. But the simpl…

When you imagine a red ball, where is that red ball physically?

Not the atoms of the neuron configuration etc., but the plane of existence where you place the red ball.

Re: Does quantum theory imply the universe is preordained?

#60

Post by DebtDeflation »

digging wrote: post #38
DebtDeflation wrote: post #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 simulati…

Actually, how are 1 and 2 different? If 2 simply refers to another layer of reality, don't we still have to figure out if it's deterministic or not? I suppose if it has its own completely different (or slightly different[1]) physics, we'd be starting over, but we'd still work our way back to the question of top-level determinism eventually). [1] Referring to cosmological natural selection as a theory of the "fine-tun…

Fair point. I'm assuming that additional layer of reality is deterministic.
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