Quantum Mechanics and randomness

[Pincho Paxton]

I would be curious about any 'not predictable in practice' things which are indistinguishable from random events. I know of no such.

I was thinking of ordinary, everyday things like flipping a coin or tossing a die. It might be good to leave QM out of it altogether for a while and just talk about statistics and probability to clarify exactly what is meant by terms like 'random' and 'determinate'.

If I flip a coin, in theory the result is completely determined by all the physical inputs: exactly how hard and at what angle I toss the coin, the properties of the air it moves through, the distance it travels and so on. (I suppose one could construct a very controllable flipping machine, perhaps in a vacuum, to test or demonstrate this, but I assume most people would take this as a given.)

However, things like the exact force I exert with my thumb are hard to measure and hard to control, and there is a very high sensitivity to initial conditions, such that in practice I can not tell in advance whether a particular coin flip will be a heads or a tails.

There is no indeterminism involved, but a coin flip can be treated as a random variable. And in fact a coin flip or roll of a die would be common ways to introduce and motivate the binomial distribution in a statistics class.

Generally, this is the case with random variables. They are used to model classes of events where we have limited information about the detail underlying the process, but we can model the overall behavior of a number of observations.

Colloquially, the outcome of a process like flipping a coin is called a random event, but strictly speaking this is misleading. Randomness is a mathematical property of a variable or distribution, and not a property of a physical event or observation.

Usually, the distinction is not important, and we treat a coin flip as if it were an observation from a distribution. We just consider this mathematical abstraction as if it were an actual thing in the world - because the mathematical model works so well.

Are you with me?

You can't have randomness with a cause. That is the linear interpretation of the universe, and would make the universe fairly useless. So basically, any situation where you can go back in time, and the same things happen twice are not random. You need situations where you can go back in time, and different things happen to have a useful universe. To be able to go back in time, and have new results can be achieved when any event has no cause to happen. And this can be seen in some forms of QM. I also include sentience as an example. (Plus I am not saying that you can actually go back in time. Just using that as an example.)

[David Quinn]

So how does [randomness] differ from saying the events "just happen"?

Why don't you understand the difference, and then get back to me, dude?

You're being evasive. There is no difference. The phrase "it just happens" refers to a spontaneous occurrence. The event just materializes out of thin air, without any contributing causes, which is identical to your conception of indeterminism.

It is a "God of the Gaps" type explanation. We don't know what causes this event, therefore God must have caused it. Or in your case, it just happens.

You wouldn't accept this kind of thinking from a Christian, so why should I accept it from you?

-

[Pincho Paxton]

So how does [randomness] differ from saying the events "just happen"?

Why don't you understand the difference, and then get back to me, dude?

You're being evasive. There is no difference. The phrase "it just happens" refers to a spontaneous occurrence. The event just materializes out of thin air, without any contributing causes, which is identical to your conception of indeterminism.

It is a "God of the Gaps" type explanation. We don't know what causes this event, therefore God must have caused it. Or in your case, it just happens.

You wouldn't accept this kind of thinking from a Christian, so why should I accept it from you?

-

Randomness is Timeline 1.
Happening is timeline 2.

So there is a difference. For example, at timeline 1 you can change you mind before you make something HAPPEN.

Also.. TRUE Randomness is a cause, and happening is an effect.

Plus randomness should have a couple of choices.

[David Quinn]

Victor wrote:

Dave Hodges: Colloquially, the outcome of a process like flipping a coin is called a random event, but strictly speaking this is misleading. Randomness is a mathematical property of a variable or distribution, and not a property of a physical event or observation.

Victor: IMO this is not a material distinction here. The distribution of quantum decoherence events is random within the given probabilistic distribution, just like the distribution of dice-rolling result is (in statistical sense, as long as we ignore the determinism of macro events). So we can simply take a shortcut and call an event 'random' if it results in a random distribution.

In other words, if a system displays randomness, it says nothing about whether that system is deterministic or not. This is because deterministic systems are just as capable of producing randomness as indeterministic systems.

Dave Hodges: Under the cosmological hypothesis of determinism there is no randomness in the universe, only unpredictability.

Victor: Hypotheses are dime a dozen. Does this hypothesis make any falsifiable predictions? if not, then it's not even a well-formed hypothesis.

The trouble is, the truth of determinism isn't a hypothesis. It is a logical fact which is generated out of the incoherence of indeterminism. An "uncaused event" is a contradiction in terms. It has no more chance of arising than a married bachelor does. Doing empirical tests to see whether the world is deterministic or not is nonsensical because it ignores the reality that indeterminism is logically incoherent. It would be like doing empirical surveys to try and discover how many married bachelors exist in the world.

In other words, there is more than one way to discredit a truth-claim or theory. If the truth-claim is an empirical hypothesis or theory, then yes, it needs to be capable of producing falsifiable predictions, otherwise it will be meaningless. But it can also be discredited on the basis that it is logically incoherent to begin with. The theory that married bachelors exist in the world can be considered a falsifiable theory, as we can go out and empirically test whether such creatures exist in the world. It passes the test of being a meaningful empirical hypothesis. But it fails the test of being logically coherent and can be rejected on that basis alone.

BTW, an interesting aside. The very descent into arguing about whether randomness really exists is already a disproof of Quinn's thesis that randomness is logically impossible. Clearly it's logically possible, and the question of whether randomness exists is an empirical question,a nd the notionof randomness itself becomes contingent. Even if, at the end of the day, we discover that the seemingly random events are in fact deterministic and predictable, that will still count against Quinn's silly view.

We can easily conceive of married bachelors and talk about them as though they could exist, as long as we don't peer too closely at such an entity and discern the internal contradiction therein. The same applies to randomness (in the sense of uncaused events arising spontaneously and unpredictability).

Incidentally, I don't like the way you are grouping determinism and predictable together. Such a coupling isn't warranted. This is because deterministic events can be just as unpredictable as indeterministic ones. From the logical perspective, there is no way to tell whether an unpredictable event is deterministic or indeterministic - although it is true that predictable events do reveal that they have been causally determined, purely on their predictability alone.

-

[Pincho Paxton]

REMOVED... POST MESSED UP BY FUDGE IN SYSTEM!

[Kevin Solway]

One of the problems is that Victor is using the term "indeterminate" (which he sometimes calls "nondeterminate"), to mean "without cause". This is a definition peculiar to himself since to scientists working in this field "indeterminate" means that we cannot determine something. That is, it doesn't mean "without cause".

[vicdan]

So how does [randomness] differ from saying the events "just happen"?

Why don't you understand the difference, and then get back to me, dude?

You're being evasive.

You are being an idiot.

There is no difference.

Sure there is.

See, quantum events are random within a given distribution. The probabilistic distribution itself is quite caused; it's which value is eventually observed, that's random.

Your argument is like saying that because a die roll result is [quasi-]random, the fact that the die was rolled doesn't count -- to claim that the die roll result is random is to claim that the die roll just happened without cause.

Suppose we have a truly random quantum die (just bear with me for argument's sake). Now John rolls the die, and comes up with 6. According to your idiotic interpretation, this is equivalent to the die roll just happening, god-of-gaps style.

What is deterministically caused, kiddo, is the probability distribution. What is random is the actual result within that distribution -- but as the number of observed results approach infinity, the shape of the observed distribution will approach the predicted distribution. To criticize this model as things 'just happening' is simply stupid and ignorant.

The phrase "it just happens" refers to a spontaneous occurrence. The event just materializes out of thin air, without any contributing causes, which is identical to your conception of indeterminism.

Like i said, you are an idiot.

You wouldn't accept this kind of thinking from a Christian, so why should I accept it from you?

You wouldn't -- you are too dumb and ignorant for that.

[vicdan]

In other words, if a system displays randomness, it says nothing about whether that system is deterministic or not.

Not purely from analyzing the resulting distribution. no. However, the randomness in QM is supported by far more than just the statistical analysis. Did you miss all the talk of impossibility of local hidden variables, and metaphysical fairy dust?

The trouble is, the truth of determinism isn't a hypothesis. It is a logical fact which is generated out of the incoherence of indeterminism.

Why don't you support that, kiddo?..

An "uncaused event" is a contradiction in terms.

only in QRS world where events are caused by definition.

Try defining Quinn as being Napoleon, and see how far that gets you.

Incidentally, I don't like the way you are grouping determinism and predictable together. Such a coupling isn't warranted.

You bloody fucking idiot, I was the one who explicitly, time and time again, distinguished unpredictability (chaos, intractability, etc.) from non-determinism.

Damn, I can't believe how dumb and dishonest you are...

[vicdan]

One of the problems is that Victor is using the term "indeterminate" (which he sometimes calls "nondeterminate"), to mean "without cause".

Oh, I am, am I?

Show me where I used the term 'indeterminate' even once, imbecile.

In case you missed it -- and you obviously did -- this is something you had projected onto me from the very beginning. I never used the term 'indeterminate' at all. i refrained from doing so precisely because in this family of terms -- indeterminism, non-determinism, underdeterminism -- every one means somewhat different things. Don't project your idiocy onto me.

I used 'non-determinism' specifically because of its computation-theoretic connotations, where it conceptually mirrors quantum-mechanical concept of superposition.

[Pincho Paxton]

If you can tell me what comes before sentience I will be impressed.

The Universe before sentience.

You might even tell me what causes the cause of sentience.

Since the Universe is the All (by definition), it cannot have a cause. There is nothing other than itself.

the beginning of the universe.

If we define "Universe" to mean the All, then there can be no beginning.

No need to go back that far though, because we can already witness QM randomness.

Randomness doesn't mean without cause.

Somebody messed up my post. That's not even what I posted??? I wouldn't post randomness has a cause.. that's completely against my oppinion. Being as I have said the opposite about 5 times already. Has my avatar on it as well, but it's been edited.

Oh well... it let me edit it. So I removed it.

[vicdan]

Ah, the sweet smell of paranoia...

Dude, get some professional help. Seriously.

[Kevin Solway]

Show me where I used the term 'indeterminate' even once

How about, "Proofs of determinism or indeterminism can't be found in the math of QM."

You seem to think that determinism and indeterminism are opposites, when in fact they have nothing to do with each other.

I used 'non-determinism' specifically because of its computation-theoretic connotations

Even in that case, "non-determinism" has nothing to do with (philosophical) determinism. It is not an opposite to determinism, but it refers to an altogether different subject.

[David Quinn]

Victor wrote:

DQ: There is no difference.

Victor: Sure there is.

See, quantum events are random within a given distribution. The probabilistic distribution itself is quite caused; it's which value is eventually observed, that's random.

Your argument is like saying that because a die roll result is [quasi-]random, the fact that the die was rolled doesn't count -- to claim that the die roll result is random is to claim that the die roll just happened without cause.

Suppose we have a truly random quantum die (just bear with me for argument's sake). Now John rolls the die, and comes up with 6. According to your idiotic interpretation, this is equivalent to the die roll just happening, god-of-gaps style.

Are you saying that the random quantum event produced within a given distribution is akin to the random showing of a 6 produced within the rolling of a dice? In other words, the two processes are fully causal, while the two results are random?

What is deterministically caused, kiddo, is the probability distribution. What is random is the actual result within that distribution -- but as the number of observed results approach infinity, the shape of the observed distribution will approach the predicted distribution.

Shouldn't the probability distribution be considered a local variable of the random quantum event in the same way that the rolling of a dice is a local variable of the resulting 6?

DQ: An "uncaused event" is a contradiction in terms.

Victor: only in QRS world where events are caused by definition.

That's not my argument. My argument is that being caused is a natural consequence of "thinghood". In other words, first I define a "thing" to be a limited portion of the totality (which immediately embraces all phenomena in the Universe, including electrons and quarks) and then I logically realize that a thing cannot exist all by itself. It needs both the existence of its own parts, as well as the rest of the totality, to give it definition and existence.

-

[vicdan]

Show me where I used the term 'indeterminate' even once

How about, "Proofs of determinism or indeterminism can't be found in the math of QM."

How about, that was Quinn's statement, moron -- in his post on the first page of this thread, on Tue Nov 13, 2007 9:00 am. it also happens to be in direct contradiction with my thesis, which is that the math of QM strongly suggests non-determinism. not that you ever cared about the contents of any thoughts, only their most superficial form -- which is why you so glibly criticized the above-quoted statement as long as you didn't realize it was Quinn's rather than mine.

You seem to think that determinism and indeterminism are opposites, when in fact they have nothing to do with each other.

Funny, ainnit, that it was Quinn who said that, and that it's him your 'critique' is therefore targeted at, your idiotic intentions notwithstanding? in fact he had contrasted determinism with indeterminism repeatedly, while i refrained from using the term 'indeterminism' even when directly replying to his passages employing it, e.g.:

Quinn: I can't really respond to the rest of your post without knowing more specifically what you mean by indeterminism.
Victor: you know full well what i mean by non-determinism [italics in the original -V]

Duuude, you are a fucking idiot.

Even in that case, "non-determinism" has nothing to do with (philosophical) determinism. It is not an opposite to determinism, but it refers to an altogether different subject.

Being as you are a clueless git, i can understand why you would believe that.

In fact computational non-determinism conceptually mirrors the decoherence conceptualization of QM, which is where quantum non-determinism comes from -- a non-deterministic Turing machine is one which can be thought of as processing the superposition of possible algorithm paths, and at the end coming up with one answer; and if more than one answer is correct, NTM is allowed to randomly emit any one of the correct answers.

I find it useful to speak of non-determinism by employing what we already know of randomness in its various guises, which is why i refuse to use the contextually barren term like 'indeterminism'. Science and mathematics are your friends.

P.S. Did i mention that you are an idiot?

[vicdan]

Are you saying that the random quantum event produced within a given distribution is akin to the random showing of a 6 produced within the rolling of a dice? In other words, the two processes are fully causal, while the two results are random?

Indeed. The probabilistic distribution itself, as a whole, is deterministic, is a result of specific causal processes, and is predictable. What is random is each specific observation result -- just as the die roll is caused, the distribution of die rolls is known and predictable, yet each specific roll is [quasi-]random.

You really have no clue here, do you?..

Shouldn't the probability distribution be considered a local variable of the random quantum event in the same way that the rolling of a dice is a local variable of the resulting 6?

No. With the die roll, if you dig deep enough, the physical events causing the roll do determine the result; but with the die roll, it's obvious that even if the result were actually random, that wouldn't mean things happen 'just because', because it's obvious that a dice must be rolled to obtain any results. This is why I asked you to imagine a truly random quantum die -- to overcome your stupid intuition block; because you surely understand dice far better than you understand quantum mechanics.

Contrawise, with QM, we know thanks to Bell's theorem that no local hidden variables could account for the apparent randomness, so the probability distribution cannot be a local hidden variable (not to mention the fact that it's not a variable, but the result).

That's not my argument. My argument is that being caused is a natural consequence of "thinghood". In other words, first I define a "thing" to be a limited portion of the totality (which immediately embraces all phenomena in the Universe, including electrons and quarks) and then I logically realize that a thing cannot exist all by itself. It needs both the existence of its own parts, as well as the rest of the totality, to give it definition and existence.

And yet you do not realize that a thing may be caused, yet might have random aspects which are not caused nor determined by anything.

[Kevin Solway]

that was Quinn's statement

So it was.

randomly

I don't understand why you think randomness is so important. It doesn't say anything about causality.

"Non-determinism" is not clearly distinguishable from "indeterminism" so far as I can see.

Did i mention that you are an idiot?

Yeah. There are people who say the word "fuck" every second word as a natural part of their language. I put you in the same category.

it's obvious that a dice must be rolled to obtain any results.

And its obvious that there must be a Universe and an observer for there to be any quantum results.

This is why I asked you to imagine a truly random quantum die

Things are either random or not. There's no such thing as "truly random".

aspects which are not caused nor determined by anything

Yep, you believe that some things can happen without any cause whatsoever. That much is clear. It is a crazy belief, but I know it is a very common one.

local hidden variables

We have much to learn about what is "local" so far as the science is concerned. We are only just beginning to learn about such things.

[Pincho Paxton]

Ah, the sweet smell of paranoia...

Dude, get some professional help. Seriously.

To add paranoia to my comment is very Bipolar of you. Plus some of your aggression could be seen as Bipolar. Are you sure you don't have BPD?

All I said was somebody messed with my post. It was completely edited into a different meaning. How is the truth paranoia?

[Pincho Paxton]

Anyway back to randomness. I think it's time to define what happens in a true random event once more.

1/ Two things can happen at exactly the same time, removing cause. Like a particle can be spinning both clockwise, and anti-clockwise at the same time.

2/ Time is segmented, and not analogue, it moves in ticks.

3/ The gaps between a tick allow for an event to happen outside of time itself.

4/ We can only observe our own timeline.

5/ Nothing causes the event to happen in our timeline.

6/ There is no cause to the event.

I will try a new example, but it works better for particles than it does for humans.

You have a left brain, and a right brain. You are considered a single person, you are a single entity. Somebody puts you on a sawmill, and cuts you in half down the middle of the two halves of your brain. You also die at this instance, and become a ghost.

In the spirit world it was impossible to put you back together again. Your two body halves hold hands, and hop around... think Harry Potter.

Now you can do two things at the same time, outside of the human timeline. You can pop into their world, and play tricks on them. Both halves of your body can play a trick at the same time.

Particles can be split between their two identities. But the split particle is a negative twin. Not only is it a nagative twin, but it is a ghostlike thing that pops in, and out of our timeline. Now the particle can do two things at once.

Two opposite things is as random as you can get. You can eat an apple, and not eat an apple at the same time.

But the main thing to remember is that our twin is real, but has not been parted from our body. So two choices are always happening at the same time, but only one of the choices gets used.

You can throw a die that produces a six, and a one at the same time, both with an equal chance of being used. The seesaw is balanced in the middle. If you go back in time, and start again, the results will change. Linear universe is broken.

[Kevin Solway]

Like a particle can be spinning both clockwise, and anti-clockwise at the same time.

Pincho, I have to tell you that the above quote is an example of why I don't read your posts. You have read too many badly-written popular magazines about science.

[Pincho Paxton]

Like a particle can be spinning both clockwise, and anti-clockwise at the same time.

Pincho, I have to tell you that the above quote is an example of why I don't read your posts. You have read too many badly-written popular magazines about science.

This isn't pop science..

http://physicsworld.com/cws/article/news/23734

Not reading my posts is just going to hold you in a state of superposition... LOL!

[Kevin Solway]

This isn't pop science..

http://physicsworld.com/cws/article/news/23734

That's exactly what I mean. It's pop science.

It is made to sound sexy for people who are not in the field by sacrificing truth and accuracy.

[Faust]

This isn't pop science..

http://physicsworld.com/cws/article/news/23734

That's exactly what I mean. It's pop science.

It is made to sound sexy for people who are not in the field by sacrificing truth and accuracy.

explain

[Pincho Paxton]

This isn't pop science..

http://physicsworld.com/cws/article/news/23734

That's exactly what I mean. It's pop science.

It is made to sound sexy for people who are not in the field by sacrificing truth and accuracy.

Ok.. so are you going to post the true sequence of events that have evoked this sexy peice of literature? (By the way, if that's sexy don't start a porn site!!! C'mon girls, get your protons out for the lads!!! Anything bigger than an Atom-full is too much!)

[David Quinn]

Are you saying that the random quantum event produced within a given distribution is akin to the random showing of a 6 produced within the rolling of a dice? In other words, the two processes are fully causal, while the two results are random?

Indeed. The probabilistic distribution itself, as a whole, is deterministic, is a result of specific causal processes, and is predictable. What is random is each specific observation result -- just as the die roll is caused, the distribution of die rolls is known and predictable, yet each specific roll is [quasi-]random.

Would you say, then, that the randomness in each case is not a property of the system itself, but a function of our inability to predict the outcome? In the case of the dice, the result of 6 is causally created by the rolling the dice, while our inability to predict its outcome beforehand makes it appear as though it is random.

DQ: Shouldn't the probability distribution be considered a local variable of the random quantum event in the same way that the rolling of a dice is a local variable of the resulting 6?

Victor: No. With the die roll, if you dig deep enough, the physical events causing the roll do determine the result; but with the die roll, it's obvious that even if the result were actually random, that wouldn't mean things happen 'just because', because it's obvious that a dice must be rolled to obtain any results. This is why I asked you to imagine a truly random quantum die -- to overcome your stupid intuition block; because you surely understand dice far better than you understand quantum mechanics.

I still haven't grasped what you mean by "truly random". Are you talking about a quantum dice that doesn't involve any causal processes at all, or are you simply referring to our inability to track its roll and/or predict a specific outcome?

Contrawise, with QM, we know thanks to Bell's theorem that no local hidden variables could account for the apparent randomness, so the probability distribution cannot be a local hidden variable (not to mention the fact that it's not a variable, but the result).

So the probability distribution is causally created by all sorts of local variables, while a specific outcome within the distribution arises without any cause at all?

DQ: That's not my argument. My argument is that being caused is a natural consequence of "thinghood". In other words, first I define a "thing" to be a limited portion of the totality (which immediately embraces all phenomena in the Universe, including electrons and quarks) and then I logically realize that a thing cannot exist all by itself. It needs both the existence of its own parts, as well as the rest of the totality, to give it definition and existence.

Victor: And yet you do not realize that a thing may be caused, yet might have random aspects which are not caused nor determined by anything.

Those aspects can also be classified as "things". So I can't see how any aspect of the event can be without cause. If we want to back-track away from this, then we are back into the territory of it "just happening".

-

[Imadrongo]

I am a little confused here too victor...

You say that if we dig deep enough into the physical factors that a dice roll is determined. However, if there are truly random inputs into the physical system on a low level shouldn't this result in our not being able to determine the outcome of a dice roll accurately? This assumes that the random input is great enough to affect something like rolling 6-sided dice....

This all comes down to whether we cannot understand all the factors, or there are random factors. We already know we don't understand all the factors at this time, and the only way to prove nothing is random would be to understand everything, which feels pretty impossible for me personally. And there is basically no way to prove something is random, all we can say is that we can't predict it, not that it is unpredictable.

I get the sense that "random" is just a practical term meaning "we can't predict it" and that "true randomness" is something like "absolute truth".