Why is Randomness so Hard to Prove?

[Lestat]

Really bad at math here, but the discussion on determinism seemed to indicate we need quantum mechanics to prove randomness exists. I don't understand...

Why can't we just use the throwing of dice? Or any other method where results are unpredictable, uncalculatable, and seeingly perfectly random? What about random number generators in computers, etc. ?

I'm sure this is a dumb question, so try to go easy on me. It just seems to me there are plenty of things without determined outcomes. Why do we need QM to disprove determinism? One other thing that bothers me...

If everything were in perpetual motion, determinism would make more sense to me. But there are clearly things in this universe that STOP. Unlike the billiard break example that someone gave, my car for instance, stops... And then goes again. This would seem to disrupt the notion that all is pre-determined by some antecedent event. At least to me.

[MelchyBeau]

throwing of dice is calculatable, if you know the variables, hand speed etc.

Melch

Random numbers in computers aren't actually random (GASP). At least, not according to the strict mathematical definition.

[hmkpoker]

Random number generators usually create an input based on the millisecond that they are activated, and enter it into a formula designed to return another number within the specified parameters. The formula tries to create as even a distribution of returned numbers as possible. No randomness here; a computer can only do what you tell it to do, even if you don't know what you're telling it.

[hmkpoker]

The real question behind any "randomness" in the universe is "is it genuinely random, or is the result just too complicated for me to predict?"

I have a hard time believing anything to be random. What could make something "random".

throwing dice is not random expecially in the context that would prove your case.. it could actually be used to hurt your case. Although we cannot yet easily calculate what a person rolling dice would hit, we know that it would be possible to do because the laws of physics can predict the outcome...but quantum mechanics doesn't have much to do with this.

random number generatiors are also not random

there are not many things without determined outcomes, and quantum mechanics may just be another thing that is not random but we cannot find a deffinite pattern in yet.

it's reeally a shame that one tiny particle winding up in an actually random location could be the only thing keeping the universe from having one definable equation... but I'm sure there is probbly more randomness in the universe if any.

[atrifix]

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Why can't we just use the throwing of dice? Or any other method where results are unpredictable, uncalculatable, and seeingly perfectly random? What about random number generators in computers, etc. ?

[/ QUOTE ]
Both of those are deterministic in the strict sense. Things like random number generators (where a computer spits out a number based on the time) are exactly the sort of thing determinists are thinking of.

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I'm sure this is a dumb question, so try to go easy on me. It just seems to me there are plenty of things without determined outcomes. Why do we need QM to disprove determinism? One other thing that bothers me...

[/ QUOTE ]
We don't necessarily 'need' QM to disprove determinism, but we need some kind of randomness. Newtonian mechanics indicated that everything in the universe was calculatable by means of force, mass, etc. Quantum mechanics is the first instance of genuinely random events being observed.

[ QUOTE ]
If everything were in perpetual motion, determinism would make more sense to me. But there are clearly things in this universe that STOP. Unlike the billiard break example that someone gave, my car for instance, stops... And then goes again. This would seem to disrupt the notion that all is pre-determined by some antecedent event. At least to me.

[/ QUOTE ]
I am really confused by this example. I'm not sure why motion affects determinism. And, as I'm sure you know, when your car is "stopped", it's still in motion.

[hmkpoker]

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I have a hard time believing anything to be random. What could make something "random".

[/ QUOTE ]

Impossible to predict even on a theoretical level. I guess something could be random, I just don't understand how they would prove the randomness is not the result of poor measuring. I'm not a quantum physicist.

Ask borodog.

[Piers]

Randomness is subjective, absolute randomness is not possible. However due to our limitations the appearance of true randomness can exist.

By projecting the universe onto a view that we can comprehend, we can demonstrate a form of true randomness that is nevertheless subjective when considering the universe in its totality.

Quantum mechanics is a model we use to analyse certain facets of the universe. Randomness is inherent to this model. There is no suggestion here that the universe is actually random, just that for our limited minds to get some sort of grasp of what is going on we need to incorporate assumptions about randomness.

Quantum mechanics does not disprove determinism; it just suggests that completely accurate predictions of the future are currently beyond us.

[ QUOTE ]
If everything were in perpetual motion, determinism would make more sense to me. But there are clearly things in this universe that STOP. Unlike the billiard break example that someone gave, my car for instance, stops... And then goes again. This would seem to disrupt the notion that all is pre-determined by some antecedent event. At least to me.

[/ QUOTE ]

I don’t really understand your point, however I suspect your intuitive feel for the subject is misleading you. You’re thinking on too macroscopic a scale.

[Zygote]

QM has an inherently random factor within the wave-function. QM is random by its own definition and does not need proof beyond this. To debunk the randomness of QM, one would need to show that something beyond the wave function could be well defined, and make more accurate predictions.

Also, the wave function's uncertainty is not proof against determinism, but since there is uncertainty, its defeinitely a reduced form of predictability. This amounts to being able to predict only the wave function itself at any point in time.

[Zygote]

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Quantum mechanics does not disprove determinism; it just suggests that completely accurate predictions of the future are currently beyond us.

[/ QUOTE ]

QM does NOT suggest that accurate predicitons are currently beyond us. QM says that the most htat can be known by anyone (whether it be a god, a superhuman or supermachine) is the wave function!

[Piers]

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[ QUOTE ]

Quantum mechanics does not disprove determinism; it just suggests that completely accurate predictions of the future are currently beyond us.

[/ QUOTE ]

QM does NOT suggest that accurate predicitons are currently beyond us. QM says that the most htat can be known by anyone (whether it be a god, a superhuman or supermachine) is the wave function!

[/ QUOTE ]

Quantum mechanics says that if you model a wave or particle using quantum mechanics then the most that can be know by anyone (whether it be a god, a superhuman or supermachine) is the wave function.

Also for the moment quantum mechanics appears the best model we have for such wave/partial dynamics.

It is important not to confuse model and reality. The choice to apply any model is always subjective.

[ QUOTE ]

Quantum mechanics does not disprove determinism; it just suggests that completely accurate predictions of the future are currently beyond us.

[/ QUOTE ]

I agree that my language was slightly sloppy.

The original poster claimed that QM could be used to disprove determinism.

The point I was trying to make is that if QM is the best model we have, then the most our current use of QM could do is show that determining the future is currently beyond us.

I was buying in to his assumption that determinism does not exist within a QM model, but pointing out that a model cannot give results outside of itself.

Personally I think the whole QM thing feels like the projection of some structure onto a subspace. If we could step back we would be able to see a way of lifting everything to some super-space where all the QM paradoxes disappear. But that’s just me guessing in the dark.

[chezlaw]

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The original poster claimed that QM could be used to disprove determinism.


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QM is not inconsistent with determinism and could never be used to disprove determinism. To see why this is true, imagine a deterministic simulation of a QM universe

[unless you make non-determinism an assumption of QM but its not a neccesary assumption]

chez

[Piers]

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It just seems to me there are plenty of things without determined outcomes. Why do we need QM to disprove determinism?

[/ QUOTE ]

[ QUOTE ]
[ QUOTE ]
The original poster claimed that QM could be used to disprove determinism.


[/ QUOTE ]
QM is not inconsistent with determinism and could never be used to disprove determinism. To see why this is true, imagine a deterministic simulation of a QM universe
[unless you make non-determinism an assumption of QM but its not a neccesary assumption]
chez

[/ QUOTE ]

That’s fine. If QM is not inconsistent with determinism, I do not need to do anything to show that QM does not disprove determinism, which is all I was trying to do.

I was instead making the point that the details of a particular model of some facet of the universe that is currently in vogue cannot be used to disprove determinism; which seems to achieve the much the same result.

[chezlaw]

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It just seems to me there are plenty of things without determined outcomes. Why do we need QM to disprove determinism?

[/ QUOTE ]

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[ QUOTE ]
The original poster claimed that QM could be used to disprove determinism.


[/ QUOTE ]
QM is not inconsistent with determinism and could never be used to disprove determinism. To see why this is true, imagine a deterministic simulation of a QM universe
[unless you make non-determinism an assumption of QM but its not a neccesary assumption]
chez

[/ QUOTE ]

That’s fine. If QM is not inconsistent with determinism, I do not need to do anything to show that QM does not disprove determinism, which is all I was trying to do.

I was instead making the point that the details of a particular model of some facet of the universe that is currently in vogue cannot be used to disprove determinism; which seems to achieve the much the same result.

[/ QUOTE ]
Yeah but you'll never convince the evidence junkies your way, they'll start wittering on about the probability that randomness exists /images/graemlins/smile.gif

chez

[gumpzilla]

[ QUOTE ]

QM is not inconsistent with determinism and could never be used to disprove determinism. To see why this is true, imagine a deterministic simulation of a QM universe

[/ QUOTE ]

How do you propose to recreate the predictions of quantum mechanics deterministically?

[chezlaw]

[ QUOTE ]
[ QUOTE ]

QM is not inconsistent with determinism and could never be used to disprove determinism. To see why this is true, imagine a deterministic simulation of a QM universe

[/ QUOTE ]

How do you propose to recreate the predictions of quantum mechanics deterministically?

[/ QUOTE ]
All that's needed is to show that our universe could be running as a simulation on a deterministic computer. (I'm obviously not claiming that's what is going on)

Computationally QM is like late evaluation, you never calculate a value until its needed.

Consider the up/down spin of two entangled particles (pretty much the classic QM experiment). This is consistent with a computer simulation that doesn't calculate the up/down values until they are needed for something. When one of the particles is force by measurement to have an up/down value the 'program' pseduo-randomly allocates the values up/down to the particles. This happens at the speed of the computer which is many orders of magnitude greater than the max speed within the simulation.

That's a bit of a hurried explanation but ask more if its not clear (or shoot it down in flames)

chez

[Lestat]

<font color="blue"> You’re thinking on too macroscopic a scale.
</font>

No doubt! I just really have a problem with determinism for some reason. I can't grasp it. I can't believe it. Most of all, I can't understand it.

[Lestat]

<font color="blue">I am really confused by this example. I'm not sure why motion affects determinism. And, as I'm sure you know, when your car is "stopped", it's still in motion. </font>

What I'm trying to figure out is how I do not have free will. I just cannot conceptualize it.

As I udnerstand it, determinism states that everything I do is caused by an antecedent event which sets everything in motion to where I do not have a choice over my actions or thoughts. Everything I do and think, I'm doing because of some causal link. Is this correct? Maybe I'm not understanding what determinism is?

So whether it was the big bang or God who set everything in motion, the point is I have no choice. Everything has already been set in motion and it's oucome pre-determined.

I'm just having a real hard time buying into this.

[maurile]

Randomness is impossible to prove because it's impossible to rule out the possibility that there's an underlying pattern which we just haven't discovered yet.

(Likewise, non-randomness is also impossible to prove. Whatever pattern we observe, it's impossible to rule out the possibility that it was just a coincidence.)

If it makes you feel better (I bet it won't) I have an equally difficult time accepting it. Intellectually I have come to the conclusion that I do not see any other options but fundamentally in the pit of my stomach it smells wrong.

[atrifix]

Well, I don't think motion is a requisite, but I get what you're saying. The car is a bad example, though, because although it's "stopped", it's still in motion. There are forces acting on it, the most important being gravity, which keeps it from floating away. And it moves at approximately the speed of the earth, whether you're driving it or stopped at a red light.

Maybe this will help you grasp determinism: imagine (assume) that your body is made up entirely of fundamental particles which are atoms. All cells, synapses, beliefs, motions, choices, are reducible to a big, finite number of atoms. Each atom doesn't have free will--it's influenced entirely by the laws of physics (causal or probabilistic). What determinism says is that the whole cannot be larger than the sum of its parts. If you're made up of atoms, you follow the same physical laws atoms follow. Since the atoms don't have free will, you don't have free will.

If that doesn't help, this is how I would formulate determinism logically: Let H be a true proposition expressing a state of the world at some time t0 before any agents existed, let L be the set of all true conjoined natural laws, and let P be a true proposition which describes the state of the world now. Determinism says that (necessarily) (H &amp; L -&gt; P). From this, along with a few other assumptions, you can deduce that you have no choice about P.

You may still disagree, but I hope that at least makes determinism clear.

[purnell]

Lestat, I (and probably everyone else here) understand your difficulty with accepting determinism. Don't let it worry you- it's merely the logical result of refusing to believe in supernatural entities. None of us can do anything other than pretend that we have free will.

[Darryl_P]

I think you might find my approach to this question appealing...

I believe determinism and free will can coexist. The reason is that humans and other living beings have a soul (or consciousness if you prefer) which operates in a different dimension from what we observe in the physical (non-living) world.

It is possible that the world of the soul does have free will while the non-living world is deterministic. Some say QM proves that the physical world is not deterministic, but only the Copenhagen interpretation does that. The many-worlds interpretation is both widely believed by leading physicists and compatible with determinism, so the question is far from resolved.

[Lestat]

My motion example was due to someone else's example of a billiard break (which did make sense to me). Basically, I understood it to mean that when you break a rack of billiard balls, it is impossible (and hence seemingly random), to determine where the balls will all finish up. Yet there can be no doubt that once the cue ball was struck, only one outcome was possible and could be no other way. This makes perfect sense to me!

So once the big bang occurs everything is set in motion and can be no other way. Ok, fine. Got it... So each new state is caused by an antecedent state or event. But what happens when something within the primary event stops? Such as tossing a ball up in the air and catching it? Now of course, I realize the ball hasn't really stopped, but the initial energy which caused the ball to briefly act against the forces of gravity has stopped. The only only way the ball can rise again is if the neurons inside my brain fire (my FREE WILL), in order to toss it again.

Now determinism would say that the neurons which fired inside my brain causing the ball to rise the 2nd time were already set in motion and couldn't have been stopped. In other words, it could've been no other way. However, I see this as two SEPERATE events which acted independently from the primary event (the big bang or whatever), because something within the antedecent event STOPPED and then started again! This disengages the agent momentarily from the primary event.

Of course, this is all a very sophomoric attempt to explain something I don't understand in the first place. But this is why I currently believe in free will. I'm thinking this belief might very well change as I come to understand determinism. But for now all the arguments I've heard in favor of determinism seem no more plausible than arguments for a god. If I open a window how can you prove this was a deterministic act? Of course, I can't prove it wasn't, but why should I have to? I wanted the window open so I opened it!

[Bork]

Determinists assume that the Principle of Sufficient Reason is true. They think a causal chain goes to back to the first event, hence everything is determined.

Leibniz’s Formulation of the Principle of Sufficient Reason:
No fact can be real or existing and no statement true unless it has a sufficient reason why it should be thus and not otherwise.

This is a poor assumption. Here is a short excerpt from a paper I wrote this last quarter that explains why:

Many things do appear to have sufficient reasons but that does not justify the belief that all positive facts have a sufficient reason. People are inclined to believe PSR because our brains are built to identify patterns and relationships. When we observe a phenomenon we assume that there is an explanation or reason for it. We do this not for any good reason, but because that is how we are wired. It is a useful survival trait to believe everything has a reason, because it leads us to search for reasons. In our quest for reasons we often make useful discoveries.

[atrifix]

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The only only way the ball can rise again is if the neurons inside my brain fire (my FREE WILL), in order to toss it again.

[/ QUOTE ]
But why are the neurons firing in your brain free? Don't we consider neurons to be just as entangled in the laws of physics as anything else? What causes them to fire?

[ QUOTE ]
Now determinism would say that the neurons which fired inside my brain causing the ball to rise the 2nd time were already set in motion and couldn't have been stopped. In other words, it could've been no other way. However, I see this as two SEPERATE events which acted independently from the primary event (the big bang or whatever), because something within the antedecent event STOPPED and then started again! This disengages the agent momentarily from the primary event.

[/ QUOTE ]
Momentarily, yes. I think I understand what you are saying, but stop me if this is a mischaracterization of your position. What you are saying is that causation is not transitive, and I agree. The big bang doesn't cause the ball to rise any more than a butterfly in India causes you to post on a message board. However, transitivity of causation isn't necessary for determinism--all that is necessary is a causal chain. E.g., the big bang causes some other state, which causes some other state, which causes the ball to rise. The big bang doesn't cause the ball to rise, but it does initiate the causal chain. In that sense, causation is not transitive, but having no choice is.


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I'm thinking this belief might very well change as I come to understand determinism. But for now all the arguments I've heard in favor of determinism seem no more plausible than arguments for a god.

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Perhaps you just disagree with determinism, which is perfectly acceptable. I am just trying to get you to understand it. However, most libertarian positions these days are extremely weak. It's really not doing so well; but of course, that has no bearing on its truth or falsity.

[atrifix]

Okay, this is a good objection to determinism, but your excerpt doesn't explain why PSR is a poor objection. What it does is explain our psychological motivation for assuming PSR. To conclude from this that it is a poor assumption is an ad hominem fallacy.

What does a denial of PSR entail? To me, it just entails randomness, because non-randomness leads back to PSR. But randomness is not free, it's just random. So either way, we don't have free will. Maybe there's a denial of PSR that doesn't entail randomness, but I don't know what it is.

[Lestat]

Thanks atrifix -

I really do appreciate your efforts in trying to help me understand determinism. You've been a BIG help!

Yes, I guess what I was saying is that causation is not transitive. And now I see what you're saying that it doesn't have to be. I need to think much more about this.

I take it libertarian position means free will? This is what has me so confused. The impression I'm getting is that determinism is a popular atheistic view, while free will is a religious one. Would you agree with this, or do I have that wrong? This is why I'm trying so hard to understand it. If you read my posts, you know I am not a religious believer. I'm trying to find out if my beliefs are conflicting. Thanks again!

[atrifix]

I don't know exactly who holds which beliefs. I'm not terribly keen on keeping track of people's religious beliefs. Religion and determinism are definitely compatible, and, I would say, not really related. All I know is that philosophically, both religion and libertarianism were both big at one point (Kant was a libertarian, Descartes offered several arguments for God, etc.), but these days they're both on the fringes. Not to say that they're wrong, but they are on the fringes.

[SNOWBALL138]

[ QUOTE ]
What determinism says is that the whole cannot be larger than the sum of its parts. If you're made up of atoms, you follow the same physical laws atoms follow. Since the atoms don't have free will, you don't have free will.


[/ QUOTE ]

Isn't this called the fallacy of composition?

[purnell]

[ QUOTE ]
[ QUOTE ]
What determinism says is that the whole cannot be larger than the sum of its parts. If you're made up of atoms, you follow the same physical laws atoms follow. Since the atoms don't have free will, you don't have free will.


[/ QUOTE ]

Isn't this called the fallacy of composition?

[/ QUOTE ]

I think the inference is justifiable in this case. A human body is composed entirely of matter, and matter is subjuct to the laws of physics, thus a human body is subject to the laws of physics.


http://www.nizkor.org/features/fallacies/composition.html

[Trantor]

[ QUOTE ]
[ QUOTE ]
The original poster claimed that QM could be used to disprove determinism.


[/ QUOTE ]
QM is not inconsistent with determinism and could never be used to disprove determinism. To see why this is true, imagine a deterministic simulation of a QM universe

[unless you make non-determinism an assumption of QM but its not a neccesary assumption]

chez

[/ QUOTE ]

I think you've alluded to a computer simulation of the universe before and here you put it forward as a possible (ie in principle) approach to show the QM is not inconsistent with determinism. BUT, this assumes it is possible, in principle, to carry out such a computer simulation wheras QM says this is not possible (as QM is understood at present, ie no hidden variable theory)

[chezlaw]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
The original poster claimed that QM could be used to disprove determinism.


[/ QUOTE ]
QM is not inconsistent with determinism and could never be used to disprove determinism. To see why this is true, imagine a deterministic simulation of a QM universe

[unless you make non-determinism an assumption of QM but its not a neccesary assumption]

chez

[/ QUOTE ]

I think you've alluded to a computer simulation of the universe before and here you put it forward as a possible (ie in principle) approach to show the QM is not inconsistent with determinism. BUT, this assumes it is possible, in principle, to carry out such a computer simulation wheras QM says this is not possible (as QM is understood at present, ie no hidden variable theory)

[/ QUOTE ]
I don't think thats right. I'm assuming by hidden variable you mean that each particle contains within it the information that will decide its measured spin. This is not the case in the computer simulation.
The simulation does not contradict Bell's inequalities if that what you mean.

chez

[Bork]

The dice behaving in an apparently random manner is not sufficient to prove genuine randomness exists. Even the things physicists observe are not sufficient in my view.

Just because we cannot see deterministic reasons for an event, it does not follow that there are none. As I hinted at in my excerpt above I do not think determinism can be proven either, so I think we are just out of luck on getting a conclusive answer to this question.

[atrifix]

Well, the example wasn't particularly rigorous, just meant to shed some light on the subject. Even if it is valid, the assumption (that all processes are reducible to fundamental particles) is pretty clearly false.

Moreover, though, composition isn't always a fallacy (unlike ad hominem, say). In this case there is sufficient justification to make the inference. Of course, the simplistic statement "atoms don't have free will, so you don't have free will" is fallacious, but I only wanted to make sure my meaningwas understood.

[maurile]

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What determinism says is that the whole cannot be larger than the sum of its parts. If you're made up of atoms, you follow the same physical laws atoms follow. Since the atoms don't have free will, you don't have free will.


[/ QUOTE ]

Isn't this called the fallacy of composition?

[/ QUOTE ]
I'm not sure what it's called, but it's obviously fallacious.

Since atoms don't have a mother, you don't have a mother. Since atoms don't have a beautiful singing voice, Mariah Carey doesn't have a beautiful singing voice. Etc.

Free will, since it depends on consciousness, is an emergent property. Just because the individual parts don't have it doesn't mean that the whole doesn't.

[atrifix]

[ QUOTE ]
I'm not sure what it's called, but it's obviously fallacious.

Since atoms don't have a mother, you don't have a mother. Since atoms don't have a beautiful singing voice, Mariah Carey doesn't have a beautiful singing voice. Etc.

Free will, since it depends on consciousness, is an emergent property. Just because the individual parts don't have it doesn't mean that the whole doesn't.

[/ QUOTE ]

Okay, this inference might be a composition fallacy (even if it is, though, there are other arguments for determinism), but it's not nearly as obvious as this. You're mischaracterizing my argument. What I meant was that "since (any collection of) atoms don't have free will, you don't have free will". Your inferences are more like "since (single) atoms don't have a mother, you don't have a mother." Obviously certain collections of atoms do have mothers.

[gumpzilla]

[ QUOTE ]

Consider the up/down spin of two entangled particles (pretty much the classic QM experiment). This is consistent with a computer simulation that doesn't calculate the up/down values until they are needed for something. When one of the particles is force by measurement to have an up/down value the 'program' pseduo-randomly allocates the values up/down to the particles. This happens at the speed of the computer which is many orders of magnitude greater than the max speed within the simulation.

[/ QUOTE ]

The pseudo-randomness is key here. It means that you've essentially put forth a hidden variable theory, since we can completely characterize the expected measurements of various quantities (since the pseudo-random generator is presumably deterministic.) This might be acceptable, but thanks to Bell's theorem it has consequences about what your theory needs to look like, and thus might run into problems with reality. For this, and some other reasons (the computer that's going to classically simulate our QM universe is going to be mind-bogglingly huge compared to our universe itself), I don't think that the prospect of QM all being a deterministic simulation (some kind of brain-in-vat exercise writ large) is terribly realistic. I guess that's not your point, but it does at least suggest that there is strong evidence for inherent randomness.

I haven't really read the rest of the thread, but I'll make a comment about randomness, one that I'd be surprised if it hasn't already been brought up. Even in the face of perfect determinism, there is such an incredible degree of complexity that there are many things that are going to be essentially random in the end because you just can't control all of the important parameters precisely enough. And in the end, that's what's important about randomness anyway.

[chezlaw]

[ QUOTE ]
The pseudo-randomness is key here. It means that you've essentially put forth a hidden variable theory, since we can completely characterize the expected measurements of various quantities (since the pseudo-random generator is presumably deterministic.) This might be acceptable, but thanks to Bell's theorem it has consequences about what your theory needs to look like, and thus might run into problems with reality. For this, and some other reasons (the computer that's going to classically simulate our QM universe is going to be mind-bogglingly huge compared to our universe itself), I don't think that the prospect of QM all being a deterministic simulation (some kind of brain-in-vat exercise writ large) is terribly realistic. I guess that's not your point, but it does at least suggest that there is strong evidence for inherent randomness.

[/ QUOTE ]
I'm not exactly sure what 'hidden variable' means but assumed it meant that the information that will decise the up/down spin is 'hidden' within the particle (or at least in the locality of the particle). If so the simulation is not an example of hidden variableness.

It is consistent with Bells inequalities as I understand it. Bell' idea is to show that either QM is random or locality is violated. The simulation violates locality (in a way consistent with the results of relativity) and so isn't bothered by bells result.

As for whether its realistic or not, thats beside the point here. The simulation is enough to prove that QM is consistent with determinism. [I don't think simulation or brain in the vat is realstic either but that doesn't mean that the universe we observe isn't entirely natural but a bit wierder than we currently think]

[Edit; Although I talk like I'm certain that's just my style (or lack of it). I originally posed this idea as a question and to the limits of my understanding it seems right. If someone can explain why QM isn't equivalent to late evaluation then I'd be very interested because that's how I currently think of QM]

chez