Posted on 06/16/2004 1:54:18 PM PDT by vannrox
TED: 2:55 pm EDT June 16, 2004
UPDATED: 3:03 pm EDT June 16, 2004
In a step toward making ultra-powerful computers, scientists have transferred physical characteristics between atoms by using a phenomenon so bizarre that even Albert Einstein called it spooky.
Such "quantum teleportation" of characteristics had been demonstrated before between beams of light.
The work with atoms is "a landmark advance," H.J. Kimble of the California Institute of Technology in Pasadena, Calif., and S.J. van Enk of Bell Labs in Murray Hill, N.J., declare in Thursday's issue of the journal Nature.
Two teams of scientists report similar results in that issue. One group was led by David J. Wineland of the National Institute of Standards and Technology in Boulder, Colo., and the other by Rainer Blatt of the University of Innsbruck in Austria.
Teleportation between atoms could someday lie at the heart of powerful quantum computers, which are probably at least a decade away from development, Wineland said. Although his work moved information about atomic characteristics only a tiny fraction of an inch, that's in the ballpark for what would be needed inside a computer, he said.
His work involved transmitting characteristics between pairs of beryllium atoms, while the Austrian work used pairs of calcium atoms. Each atom's "quantum state," a complex combination of traits, was transmitted to its counterpart.
Key to the process was a phenomenon called entanglement, which Einstein derided as "spooky action at a distance" before experiments showed it was real.
Basically, researchers can use lab techniques to create a weird relationship between pairs of tiny particles. After that, the fate of one particle instantly affects the other; if one particle is made to take on a certain set of properties, the other immediately takes on identical or opposite properties, no matter how far away it is and without any apparent physical connection to the first particle.
Very good article, thanks.
The other effect that replication technology could have is that we wouldn't need much farmland. You could convert farnland to homes, build additional freshwater reservoirs, etc.
A lot of material industries would go out of business, but think out much less polution there would be, if instead of manufacturing things, we just replicated them.
In fact we could replicate gasoline. Interstates would last longer, because much of the long distance heavy trucking industry wouldn't be necessary.
You're quite welcome! Glad to have been of service.
Fudd's First Law of Opposition: "If you push something hard enough, it will fall over."
Yup, but without all the wierd transdimensional metaphysics.
I wouldn't be too sure about that just yet...
Two words. Penthouse Holodeck.
"Scientist estimate that by the end of this century, via the means of virtual reality, a man will be able to simulate making love to any woman he wants through his television set. You know folks, the day an unemployed ironworker can lie in his BarcaLounger with a Foster's in one hand and a channel-flicker in the other and **** Claudia Schiffer for $19.95, it's gonna make crack look like Sanka."-- Dennis Miller, "The Rants"
The EPR-Bell correlations, and quantum entanglement in general, form the essential new ingredient which distinguishes quantum from classical information theory, and, arguably, quantum from classical physics.
[QEC] achieves the apparently impossible, since the computation preserves quantum coherence even though during its course all the qubits in the computer will have relaxed spontaneously many times.
You will find in the course of reading this thread that some appear quite adamant that neither phenomenon is the case. In my view, such people are best ignored (gently, if at all possible) until such time, if ever, that experiments begin to bear out their expectations and not different ones, as the latter has been the case to date..
Here, in a nutshell, is the causal problem with an ansible.
Simultaneity is frame-dependent. It has to be frame-dependent.
If an Earthbound ansible sends an instantaneous message to a 1-lightyear distant starship, travelling away from Earth at relativistic velocities, the message must, according to the Earth's frame, be received by the starship when it is one lightyear from Earth. So we have two events with well specified locations and times: a "send" event on Earth, and a "receive" event on the starship. The problem is this: in the starship's reference frame, the send event necessarily happens a significantly long time after the receive event. (If you don't believe that this is true, or don't understand why this is true, then you don't have a proper conceptual grasp of special relativity, and must learn the math first.)
Now, you've said that I'm "privileging" the starship's frame. Why should I calculate the time ordering in that coordinate system? If everything works in the Earth's frame, why isn't that good enough? Here's why: it's because of the principle of relativity states that ALL of the physics must ALWAYS work out perfectly in ALL frames. If I can find one frame--any frame--where an absurdity arises, then one of the problem's assumptions must be wrong. In this case, the one frame I've found is the starship's frame. The absurdity is that a later event causes an earlier event. The wrong assumption is that an ansible exists.
The problem is this: in the starship's reference frame, the send event necessarily happens a significantly long time after the receive event.
I neither disbelieve that nor do I misunderstand that.
Here's why: it's because of the principle of relativity states that ALL of the physics must ALWAYS work out perfectly in ALL frames.
This appears to be the crucial source of our disonnance. To my understanding, the conception of wormholes is that they break the reference frame symmetry. Now, in your formulation, it appears one of the following is the case:
1) The conception of wormholes is wrong; the reference-frame symmetry is not in fact broken.
2) My conception of wormholes is wrong; the symmetry is not currently thought to be broken.
3) My analogy between wormholes and quantum entanglement is incorrect; our 'ansible' as posited would not break the symmetry.
Now, I would understand where you're coming from if you would clarify which of these three you hold to be the case (or what, if there's something altogether separate I'm missing).
Contrary to your earlier assertion, I am not wedded to any particular conception of these phenomena. In fact, I would say I am the most neutral observer commenting here since I am not wedded to anything whatsoever at all besides where the empirical science takes us..
If the reference-frame symmetry is not broken, then there is no question that there would arise causality violations.
And you need not go into detail whichever the case. Just tell me which of those three items is the source of our dispute so that I can tell you why I hold the view that you find erroneous, so that you can tell me why you believe that I am wrong. This need not be the adversarial process we've managed to turn it into..
You were wrong when you stated that I don't stop to consider that you probably have a good reason for saying anything that doesn't jibe with my understanding. Quite to the contrary, that's what I've been struggling with throughout but whatever it is doesn't seem to be getting communicated.
I don't enjoy arguing with you. I have little doubt that you know your stuff quite well and much better than I do. I do still think we've been talking past one another, however. Maybe I'm wrong on that..
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