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Posted on 11/14/2014 9:04:13 PM PST by LibWhacker
FIFTY years ago this month, the Irish physicist John Stewart Bell submitted a short, quirky article to a fly-by-night journal titled Physics, Physique, Fizika. He had been too shy to ask his American hosts, whom he was visiting during a sabbatical, to cover the steep page charges at a mainstream journal, the Physical Review. Though the journal he selected folded a few years later, his paper became a blockbuster. Today it is among the most frequently cited physics articles of all time.
Bell’s paper made important claims about quantum entanglement, one of those captivating features of quantum theory that depart strongly from our common sense. Entanglement concerns the behavior of tiny particles, such as electrons, that have interacted in the past and then moved apart. Tickle one particle here, by measuring one of its properties — its position, momentum or “spin” — and its partner should dance, instantaneously, no matter how far away the second particle has traveled.
The key word is “instantaneously.” The entangled particles could be separated across the galaxy, and somehow, according to quantum theory, measurements on one particle should affect the behavior of the far-off twin faster than light could have traveled between them.
Entanglement insults our intuitions about how the world could possibly work. Albert Einstein sneered that if the equations of quantum theory predicted such nonsense, so much the worse for quantum theory. “Spooky actions at a distance,” he huffed to a colleague in 1948.
In his article, Bell demonstrated that quantum theory requires entanglement; the strange connectedness is an inescapable feature of the equations. But Bell’s proof didn’t show that nature behaved that way, only that physicists’ equations did. The question remained: Does quantum entanglement occur in the world?
(Excerpt) Read more at nytimes.com ...
Yes, it’s been tested. It’s real, and it tends to support spiritual belief.
Quantum Entanglement=Obama
Theory proved...
The really brilliant ones are tremendously humble, in my experience. It’s the impostors who have the huge egos.
This is where lay people -- and some great physicists -- fail in their conceptualization. There is no "instantaneous."
The closest we could come is a proof that the wave function of one particle collapses simultaneously with the measurement on the other. Simultaneity in Minkowski space is well defined. "Instantaneous" means nothing at all.
No one [except people making conceptual errors] has ever claimed that the collapse of the wave functions of entangled particles satisfy a spacelike connection. However, there is no experiment one could devise that would prove the spacelike connection existed. This is because all of the entanglement experiments designed to test causality violations are measuring quantities which have no measurement along any space-time dimension. The easiest to see is intrinsic spin. The basis vectors in Hilbert space for "spin" don't have any space or time components. They don't project onto spacetime axes at all. This is why the no communication theorem applies.
People find the invocation of nonlocality [which is not the same thing as simultaneity] astonishing and weird -- except when they overlook it, which is most of the time; but it's already present in the classical physics of Newton and Maxwell, as well as the quantum physics of Schroedinger, Dirac and Klein-Gordon Equations -- as metaphysics.
In Newton's world, F=ma holds throughout the universe. That's about as nonlocal as you can get. And the laws of classical and quantum physics both have that kind of nonlocality or they would not be useful for getting any answers.
Yeah, what he said.
If you measure the polarization of randomly selected photons coming out of a laser, you will generally find that unless you have prepared them in some way (by bouncing them off a refractive surface or passing them through a polarizer, for example) that their polarization states are random. One of the ways you know that someone is messing with them downstream of you would be by measuring their polarization, and discovering that they're all right-handed polarized.
OK, now, let's say, just for the sake of simplicity that you prepare two [very] high energy gamma rays by smashing an electron and a positron into each other. To conserve momentum the γ particles will fly off in pairs, in opposite direction and at right angles to the two incident electron-positron pairs. To preserve angular momentum, the two γ rays will have opposite polarization.
Now, when you put a detector on one side of the room, at right angles to the incident electron-positron pairs, you will see that when you measure the polarization of resulting γ rays, they are all over the place, from perfect alignment with your detector, to perfect misalignment and every angle in-between. But immediately AFTER you take your measurement, quantum theory says that the wavefunction of the measured photon "collapses." It is now in a state of polarization in 100% alignment with your detector. And in fact, if you go slightly downstream with a second detector, you will discover ALL of the photons indeed have 100% alignment with the first detector; they are no longer randomly polarized. Your first polarization detector has put them in a stationary-state or eigenstate of polarization, and the second detector [and third, and fourth, and however many you want to add after the first detector] will always see the polarization eigenstate corresponding to the axis of the first detector.
If, instead of putting your detectors on the left side of the room, you put them on the right side of the room, you will observe exactly the same thing. You will see random polarization states of the produced γ rays, until after they've passed through your 1st detector, and whatever the alignment of your detector was, after they've passed through it, they will all be aligned with your detector 100% when their measured at the second detector.
Nothing mind-blowing so far. In fact, if you did not see the same thing on both sides of the room you would certainly suspect a problem with your geometry, the room, or something. Physics cannot depend on which side of the room you place your instruments.
Now, here's the interesting twist. γ particles are coming off in both directions, so you can look at both γ streams. On the left hand side of the room, put a first detector, say 20 feet from the pair-production collision site. Add a second detector at 35 feet. On the right hand side of the room, put a detector at 35 feet, but leave out the first "collapsing" detector. Guess what you see? On the left hand side of the room, 1st detector sees what it saw before. Second detector sees what it saw before. But on the right hand side of the room, the detector sees γ rays which are 100% polarized -- in the direction OPPOSITE of the 1st detector on the left hand side of the room. The 1st detector has thrown the &gamma photons into collapsed wavefunctions with polarization as expected -- and it has also collapsed the wavefunctions of the photons streaming away to the other side of the room, even though those photons have never passed through the first detector.
This has happened because of entanglement. When the wavefunction of the photons heading left are collapsed into an eigenstate, in order to conserve angular momentum, the photons heading right must also collapse into an eigenstate with exactly the opposite polarization, so that their net angular momentum is zero. The two particles are therefore "entangled." They are actually a two-particle system composed of a single wavefunction. If you change the polarization of one photon, you will change necessarily the polarization of the other. And based on the experiments we can do, it appears that this entanglement is not affected by the distance in between the events of measuring them.
So beaming up the democrats to Neptune is possible, hopefully by 2016
What happens to them after that is of little interest to me...
Obamacare architect Jonathan Gruber has done it all over the USA.
...Let me get this right...you are in fact living among the stars ,traveling at self determined speeds and passing through time as you understand it to be,and yet wonder still why your measurements are slightly askew. This is indeed a fine example of being “Quantitatively Entangled”...
“Is Quantum Entanglement real?”
“It’s real, and it’s spectacular!”
(channelling Seinfeld).
Oh God
so I don't believe any of it or pay any attention to it.
ok so you all know that their global warming lie is a lie and a hoax
but all of you here fell for the BP oil “catastrophe” . it wasn't as bad as the media made it not by a long shot
you all think a football player hitting his wife on an elevator is news? not news but it's to distract us
o the ebola fearmongering. i will meet any of you here next in 6 months . the ebolo threat will magically be gone. have you noticed after the election the intense wall to wall coverage of ebola already is being reduced?remember the bird flu : you all fell for that too. see even here in 6 months there will hardly be any coverage of the “ebola threat” .conservatives still trust the mainstream media or news media. if you don't know who the enemy is how can we win any battle? the key to winning any battle is identifying the enemy and that enemy is the mainstream media , the news media and the NY times.
Excellent point..!
Why it can easily be seen that a waggling dimorat tongue in California causes reporters at the NYT to spin dramatically... :)
Ahh but Dr Cooper at Caltech suggested that the entropy emanating from entangled particles created unmeasurable results and spin angle that could not be calculated.
Isn't this more or less what the Aspect experiments did?
No.
This is the conceptual crux of the issue that I am talking about. The various Bell experiments establish violation of local realism. They do not establish that the collapse of the state vectors are events which are spacelike separated; if they did, the No Communication Theorem would be violated.
We can assume that they are. But we cannot prove that they are, because we cannot transmit the results of our measurements to each other in any Lorentz frame faster than the speed of light, and until we communicate our results to each other, neither of us actually has experimental evidence of what the other already knows.
And notice also how stringent this condition is: It holds in every Lorentz frame. If it did not, we could put a "man in the middle" who could violate causality.
Well, the obvious answer is to build a subspace ansible. What is this, the 21st century or something?
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