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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?

#41

Post by hermannj314 »

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…

It's simulations all the way down.

Re: Does quantum theory imply the universe is preordained?

#42

Post by Filligree »

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…

Many-Worlds? Or does that fall under #2 for you?

Re: Does quantum theory imply the universe is preordained?

#43

Post by cb321 »

nyssos wrote: post #25
elromulous wrote: post #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.

We don't. What we know is that we can't have all of 1. locality (no backwards causation / FTL information transfer) 2. determinism 3. counterfactual definiteness (unperformed measurements still have single definite results: we can talk meaningfully about what we would have seen had we done a different experiment) 4. QM gives correct predictions. Objective-collapse interpretations (like the version of Copenhagen descr…

Bricmont does a good job of discussing entropy, arrow-of-time, and irreversibility, information and probability in a purely classical statistical mechanics setting in https://arxiv.org/abs/chao-dyn/9603009 .

Bricmont has continued to write/expound upon these ideas ever since and more recently "come out" as a non-local hidden variables proponent of the de Broglie/Bohm variety which rejects your (1. locality) for which you left out an example. :-)

Sometimes people refer to giving up "locality" in this context with the mouthful "a preferred fundamental foliation of spacetime". { "fundamental" here does the work to block the Cosmic Microwave Background / "average rest frame" which people have no trouble treating as a preferred inertial reference frame that is "merely contingent" not "fundamental", although Ernst Mach might have begged to differ, but that is further afield. :-) }

Re: Does quantum theory imply the universe is preordained?

#44

Post by munch117 »

Appealing to quantum theory to defend free will does not make sense.

If the quantum randomness is fundamental, and reality is stochastic at heart, that makes it non-deterministic, but it doesn't make it any less mechanical. It's in the name, after all: Quantum mechanics. If there is any guiding light to the randomness, any pattern to how the random choices come out, then it's not really random, is it?

So, if you think that a deterministic reality is devoid of free will, then you must equally think that a Copenhagen-interpretation fundamentally stochastic reality is devoid of free will.

Re: Does quantum theory imply the universe is preordained?

#45

Post by [deleted] »

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"

[deleted]

Re: Does quantum theory imply the universe is preordained?

#46

Post by throwawaymaths »

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"

Of course every other QM interpretation is also unfalsifiable, e.g. Copenhagen (we have no definition of what constitutes an observation) or many-worlds (obviously unfalsifiable save for actually tunneling through into another universe and coming back to tell the tale)

Re: Does quantum theory imply the universe is preordained?

#47

Post by simiones »

PheonixPharts wrote: post #24
danbruc wrote: post #22

Earlier quoted context omitted.

"Random" is a property of your mind, not of the world. Limited information about the initial state is one source of randomness but not necessarily the only one. Whether there is true randomness in the universe is at very least an open question.

Can you clarify what "true randomness" means out side of the context of human agency and perception? Can you also give an example where "true randomness" would differ from the randomness I describe on the actions a human would take? That is to say, if a my internal model of the world tells me a coin landing on heads is 50/50 how does "true randomness" or not of the resulting coin toss impact how I should gamble on co…

> Can you also give an example where "true randomness" would differ from the randomness I describe on the actions a human would take? That is to say, if a my internal model of the world tells me a coin landing on heads is 50/50 how does "true randomness" or not of the resulting coin toss impact how I should gamble on coin tosses?

It's pretty simple. If the world is fundamentally deterministic, then you should only gamble with someone who you believe doesn't possess knowledge you don't. If an advanced alien or an angel offers to call a coin toss, you shouldn't take their bet, since they might know how to determine the result of the coin toss based on the weather and the color of the coin tosser's pants.

On the other hand, if the universe is fundamentally random at every turn, then you can safely take the bet: nothing they know could give them more information than you have about the result of the coin toss.

This is very similar to the difference between pseudo-random number generators (PRNGs) and sources of true randomness in a computer. There is no test you could do on the outputs of an RNG to determine if it is a (good, cryptographic-grade) PRNG or if it is a "true" RNG. However, if you're gambling based on the results of a PRNG, you should try to find out if the one you're gambling against doesn't happen to know the seed (in which case they can predict with 100% certainty what the next number will be).

Re: Does quantum theory imply the universe is preordained?

#48

Post by throwawaymaths »

nyssos wrote: post #25
elromulous wrote: post #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.

We don't. What we know is that we can't have all of 1. locality (no backwards causation / FTL information transfer) 2. determinism 3. counterfactual definiteness (unperformed measurements still have single definite results: we can talk meaningfully about what we would have seen had we done a different experiment) 4. QM gives correct predictions. Objective-collapse interpretations (like the version of Copenhagen descr…

Correct me if I'm wrong, but I don't think we even know what "collapse" is. Maybe a better way to say it is that arguments about what is collapse are at the root of distinguishing interpretations

Re: Does quantum theory imply the universe is preordained?

#49

Post by simiones »

nyssos wrote: post #36
PheonixPharts wrote: post #21

Earlier quoted context omitted.

Does believing that gravity exists mean a person will not roll down a hill? Why would belief that we are just agents responding predictably to stimuli imply that one would not respond predictably to stimuli ? The fact that ones behavior does not change when one acknowledges that all behavior is deterministic and predetermined seems evidence in favor not against that hypothesis.

> 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 predictable from the initial conditions of the universe.

Re: Does quantum theory imply the universe is preordained?

#50

Post by nyssos »

throwawaymaths wrote: post #48
nyssos wrote: post #25

Earlier quoted context omitted.

We don't. What we know is that we can't have all of 1. locality (no backwards causation / FTL information transfer) 2. determinism 3. counterfactual definiteness (unperformed measurements still have single definite results: we can talk meaningfully about what we would have seen had we done a different experiment) 4. QM gives correct predictions. Objective-collapse interpretations (like the version of Copenhagen descr…

Correct me if I'm wrong, but I don't think we even know what "collapse" is. Maybe a better way to say it is that arguments about what is collapse are at the root of distinguishing interpretations

Collapse is when you go from a generic quantum state to an eigenstate of a given measurement operator. The disagreement is about whether this is an objective feature of reality, an artifact of semiclassical approximation, or not a real physical process at all.
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