Quantum mechanics and randomness

[inflector]

Why should one care about what "most consider it" to be.

It's called a theory or an interpretation by different groups. I haven't seen anything that tells me it is anything other than an interpretation. But I'm open to being educated.

And to know what it is one needs to study it and to use it. Tunneling times predictions are different from those of the standard qm for the simple reason that in standard nonrelativistic qm time is not an "observable" like position or momentum or energy. Therefore all questions about time of arrival must be dealt in qm by some kind of rather arbitrary tricks. This is not so in some of the alternative theories, including dBB.

What are the specific reasons that the arbitrary tricks of which you speak cannot be applied with dBB?

I haven't seen any data or papers that suggest that dBB provides different predictions. Since you must know something I don't here, can you point out any specific papers?

 

[wuliheron]

I assume you were replying to arkajad?

Yes, sorry if that wasn't clear. I'll try to quote people more often.

 

[nismaratwork]

Why should one care about what "most consider it" to be. One should care what it is and not what it is "considered to be". And to know what it is one needs to study it and to use it. Tunneling times predictions are different from those of the standard qm for the simple reason that in standard nonrelativistic qm time is not an "observable" like position or momentum or energy. Therefore all questions about time of arrival must be dealt in qm by some kind of rather arbitrary tricks. This is not so in some of the alternative theories, including dBB.

Because with few exceptional minds aside, when you're swimming upstream in a well established field you're going the wrong way. QM doesn't present the pat answers that dBB does, but what it DOES do is be infallibly predictive so far... dBB can only MATCH QM.

I also note that you said alternative theories, plural... what other theory exists which matches the predictions of QM other than... QM... and dBB?

 

[arkajad]

I also note that you said alternative theories, plural... what other theory exists which matches the predictions of QM other than... QM... and dBB?

Theories with a a dynamical state reduction. There are several such.

"(QM) but what it DOES do is be infallibly predictive"

And when it fails it is said that it is beyond its domain of applicability or that we have a wrong model. Clever.

 

[nismaratwork]

Theories with a a dynamical state reduction. There are several such.

I'm genuinely unfamiliar with them! I thought that QM and dBB were the only two in the building so to speak, do you have any links to these others that I can read about? I would appreciate it, and if they're the type to violate PF guidelines just PM me... I'm curious, not trying to sucker you.

 

[Pythagorean]

I'm genuinely unfamiliar with them! I thought that QM and dBB were the only two in the building so to speak, do you have any links to these others that I can read about? I would appreciate it, and if they're the type to violate PF guidelines just PM me... I'm curious, not trying to sucker you.

It's an easy google; it pertains to the EPR paradox.

 

[nismaratwork]

It's an easy google; it pertains to the EPR paradox.

Done... so something like this? http://arxiv.org/abs/0907.2327

 

[arkajad]

@nismaratwork
And references there.

 

[nismaratwork]

@nismaratwork
And references there.

OK, gotcha, thanks arkajad, Pythagorean, I obviously have a lot of reading to do.

 

[kfmfe04]

Pulling balls from a bag (with replacement) produces a stationary random distribution; ie the higher moments of the distribution is bounded/fixed and is not a function of time.

Is this also true of qm randomness? Aren't there different degrees of mathematical randomness?
I suspect that qm randomness is "messier" but I don't understand it enough to assess.

 

[arkajad]

Pulling balls from a bag (with replacement) produces a stationary random distribution

Not necessarily. For instance you may like a particular ball and pull it from the bag every time. It produces random distribution if it is random to begin with.

 

[kfmfe04]

Not necessarily. For instance you may like a particular ball and pull it from the bag every time. It produces random distribution if it is random to begin with.

Is your point that if I like a particular electron, I cannot pull it every time because qm randomness is more random in that sense? Please clarify.

 

[arkajad]

Is your point that if I like a particular electron, I cannot pull it every time because qm randomness is more random in that sense? Please clarify.

No one knows for sure. It's like looking at a message that looks like a random pattern of letters. It may well be an encrypted message. Once you know the decrypting code - it becomes meaningful. Is there some meaning in the apparent randomness of quantum events? There may be, but it may be beyond our decrypting capabilities. But such speculations belong rather to the philosophy section. The fact is: we can simulate quantum phenomena (double slit experiment, EPR, whatever) on our classical computers using pseudo-random algorithms and we can make our simulations to approximate real phenomena to a reasonable degree. It is just computationally very costly. Nature does it naturally in an apparent effortless way. And that's a mystery.

 

[ThomasT]

Pulling balls from a bag (with replacement) produces a stationary random distribution ...

Not necessarily. For instance you may like a particular ball and pull it from the bag every time. It produces random distribution if it is random to begin with.

I have to agree with kfmfe04 on this. It doesn't matter how much I might like a particular ball, if I don't know the order of the balls inside the bag to begin with, even though I know which balls are in the bag and that they're in a particular order to begin with, then my ball pulling will produce a random distribution.

I suppose that the "to begin with" wrt quantum physics is it at the level of physicists' "pulling balls from the bag" -- since, as you seem to indicate, "no one knows for sure" what's in the "bag" that physicists are probing to begin with?

So, might one say that, unlike the circumstantial ignorance which produces the random distribution of balls pulled from a bag, quantum randomness is based on a profound, principled (via qm), and quite possibly permanent ignorance of the deep reality of nature.

 

[nismaratwork]

I have to agree with kfmfe04 on this. It doesn't matter how much I might like a particular ball, if I don't know the order of the balls inside the bag to begin with, even though I know which balls are in the bag and that they're in a particular order to begin with, then my ball pulling will produce a random distribution.

I suppose that the "to begin with" wrt quantum physics is it at the level of physicists' "pulling balls from the bag" -- since, as you seem to indicate, "no one knows for sure" what's in the "bag" that physicists are probing to begin with?

So, might one say that, unlike the circumstantial ignorance which produces the random distribution of balls pulled from a bag, quantum randomness is based on a profound, principled (via qm), and quite possibly permanent ignorance of the deep reality of nature.

In QM, it's also possible that the type and number of balls is constantly in a state of flux, independent of our examination... although I still don't see how that makes the example "more random".

 

[yrreg]

I have not read to the end of the thread so far.

My idea is that the randomness in quantum mechanics is according to my intelligent thinking only random to our direct or indirect empirical evidence.

On the basis of indirect empirical evidence I like to bring in the nose in our face which on the one hand is supported by direct empirical evidence as regards its objective or empirical existence, on the other is an indirect empirical evidence for what I like to call dark order that prevails all the way from QM and even deeper, deeper and deeper and deeper that scientists want to go into, up to the nose in our face, which is stable in our face and is working or serving to enable us to breathe comfortably when we are in a healthy state of living existence.




Yrreg

 

[Pythagorean]

I certainly hope QM isn't the "end" of science.

 

[latter]

with regards to this idea "pulling balls from the bag"being in any way random is a assumption based on believeing the intial conditions are exactlly the same each time.
it also come from us having absolutlly no idea really why are arm,hand is where it is in space .
there is a assumption that this is some how random.
take a gun fixed in position firing at target, when the bullet goes in a different position you immediately think of the wind and then other reasons because you know the gun is fixed in same position(ie:at some point the experiment was in exactly the same position as before) ,people are assumming that the pulling balls from a bag has a similar fixed intail conditon this then leads to the assumption that because balls are different each time that this must be random .this is not true.
it is that we can not connect the way are hand moves and clenches with with early events in the past,for instance i might of moved my hand left and down and clenched because it is a mixture of a agrument with the with the wife 3 weeks ago and other people have be wearing red a lot lately.and this is the cause of the position of my hand at this moment in time.of course that is a example it could be anything and that is the point we don't think about it atall. its not genneral knowlegde.this problem coupled with thinking the intial conditons start the same each time leads us to assume that a random event has occured.

also the way the balls are picked up and put into the bag is also not random there are connections to the past.
therefore dis regarding uncertainty p. for now
and only relieing on pulling balls from a bag we cannot say there is something random from this atall. it is compeletly determined and if all intial conditions could be know we could predict the order of picked balls with ease.
remmeber this is disregarding uncertainty p.
picking pulls from a bags is a determined process and there is no random in it.