Physics Question: Quantum Entanglment

[MEKer]

OK---this is bugging me and hopefully you Physics guys can clear it up.
In Quantum entanglement I just don't get what guarantees any 2 particles are correlated. Is it because in tests the particles are birthed from the same piece of matter? Does that then mean that, lets say, ALL electrons bursting out from the same piece of "stuff" are ALL inherently correlated and subject to this quantum entanglement? Hmm, but that would mean they lost earlier familial (so to speak) correlation unless they were original in that piece of matter from the Big Bang. Well,anyway...

OK,then so instead of a left/right, 2-electron experiment, how about measuring, say, the axis spin of 1 electron going left and ALL the rest going right (assuming you have the required number of detectors there). Measure the left one. Theory says ALL the others spontaneously take on the same measurement result 50% of the time (per Prof Aspect's validated experiments)?

So are we saying, in a rough way, the quantum universe is then a whole bunch of particle family trees with changing family identities as matter is made and remade?

Or is it ANY 2 particles measured at the same time "magically" develop this instantaneous correlation regardless of distance?

Please note I am not addressing uncertainty, simultaneity or special relativity issues (I don't think I am??).

Dammit, now I have a headache........



Oh, oh!!------I just made up a physics joke!!:
"I have a really small car with a little problem. Anyone know of a good quantum mechanic?"

 

[powderfinger]

huh?

 

[champbassist]

Calling Brad Barker. Calling Brad Barker

 

[IconBasser]

my solution to you: visit sciforums.com and post this question in either the general science forum or the physics and math forum. Those guys are much more knowledgeable.

 

[Muddslide]

I remember reading a paper in the now-defunct magazine Omni that had been "dumbed-down" for laypeople in which some scientist theorized that there was actually only ONE electron in the whole universe, but that it just moved really, reeallly fast.

 

[tastybasslines]

Well, first you need to take the vertical approach of the optical illusion, providing you with the innermost conception with the utmost vitality of both the concave and convex paradigms.

Only then can you solve it grasshoppa.

 

[Selta]

The particles have to interact (physically) somehow to become entangled. They don't just randomly become entangled. Also, if I'm reading your OP correctly, you're treading closely to the EPR Paradox.

 

[fdeck]

Or is it ANY 2 particles measured at the same time "magically" develop this instantaneous correlation regardless of distance?

I don't think so. I think that the particles have to be correlated in the sense that a measurement on one tells you something about the other. Something has to link them, such as (in the case of the Aspect experiment IIRC) a conservation law.

I remember a senior physics lab experiment in which we had some sodium-22, which gives off a pair of gamma rays. The process ensures that the gamma rays have to be traveling in opposite directions with equal energy. So, if you captured one gamma at a particular angle, you'd know where the other gamma was at the same time. We were able to observe that using electronics that detected the correlation between the signals from two detectors. It wasn't a quantum entanglement experiment, but it shows how you can get a pair of correlated particles.

 

[i_got_a_mohawk]

As someone who works in physics.

I'm glad I don't need to worry about (much) in the way of QM!

A lot of how you take on/understand it, will come from your level of physics knowledge. But tbh, not even the top academics in the field seem to really know what's going on

 

[MEKer]

The particles have to interact (physically) somehow to become entangled. They don't just randomly become entangled. Also, if I'm reading your OP correctly, you're treading closely to the EPR Paradox.

The EPR theory was conclusively shown to be wrong. I just can't define the underlying cause that makes any particle become entangled with this or that other particle. Or lets say: what decides they are. But, yes, entanglement seems to be conclusive as a true piece of QM.

 

[*smb]

I had the pleasure of meeting Alain Aspect once. Complete genius, ridiculous moustache. At the time the New Scientist was really talking up this idea someone had come up with that if you had entangled particles and you measured, say, polarisation of one lot and sent the others around loads of optical fibres for a while and then measured those, by changing what you were measuring on the second lot you could send some kind of signal back in time. Aspect explained really simply that this was just nonsense because to understand what the message meant you'd need to know what measurement was being taken on the second set of particles. I found it interesting anyway. He said a lot of other really good stuff that I wish I could remember.

 

[dbhokie]

From what I understand, that is the crux of the whole argument, and i feel you are creeping into an open-ended question.

Entanglement from observations known has a correlation with an original physical interaction. The debate centers around how there is this correlation (or correspondence) between the particles. Whether it is preset from time of separation, which would seem to mean that there is immense complexity within the particles dictating all future mechanics, or some other type of "magical" (which all that means is not understood) way.

That seems to be your last two question, but the thing is, if you could answer those questions, then you would solve a lot of fights.

 

[MEKer]

I had the pleasure of meeting Alain Aspect once. Complete genius, ridiculous moustache. At the time the New Scientist was really talking up this idea someone had come up with that if you had entangled particles and you measured, say, polarisation of one lot and sent the others around loads of optical fibres for a while and then measured those, by changing what you were measuring on the second lot you could send some kind of signal back in time. Aspect explained really simply that this was just nonsense because to understand what the message meant you'd need to know what measurement was being taken on the second set of particles. I found it interesting anyway. He said a lot of other really good stuff that I wish I could remember.

Yes, he was basically complaining about the quantum measurement paradox of the Heisenberg Uncertainty Principle issue which boils down to either/or, waveform collapse probabilities, etc----another, atho sometimes involved, subject from my base question.

 

[MEKer]

From what I understand, that is the crux of the whole argument, and i feel you are creeping into an open-ended question.

Entanglement from observations known has a correlation with an original physical interaction. The debate centers around how there is this correlation (or correspondence) between the particles. Whether it is preset from time of separation, which would seem to mean that there is immense complexity within the particles dictating all future mechanics, or some other type of "magical" (which all that means is not understood) way.

That seems to be your last two question, but the thing is, if you could answer those questions, then you would solve a lot of fights.

Oh, it not so much an argument I am asking about. We KNOW entanglement (and as you very aptly put it: correspondence) happens and that it is NON-LOCAL (that is what EPR was unsuccessfully trying to disprove, saying quantum effects are only local)---again, I am wondering what is the basis for the quantum decision that any two particles are correlative. I actually cannot find that addressed anywhere. Most of the other issues involved ARE dealt with to varying degrees of success/completion except that one. And yeah, HAD I an answer I'd get a prize. If I can FIND an answer I'd get a happy-surge.