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Quantum Dots Might Be Key For Teleportation
Posted by
Zonk
on Sun Jun 24, 2007 02:34 AM
from the trek-is-now dept.
from the trek-is-now dept.
prostoalex writes "Researchers from Nanyang Technological University in Singapore have created a model teleportation system using quantum dots. PhysOrg reports that 'tiny clusters of atoms known as quantum dots may be excellent media for quantum teleportation, a physics phenomenon in which information — in the form of a quantum state, a very specific mathematical signature of an atom — can be transmitted almost instantaneously to a distant location without having to physically travel through space.'"
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Researchers Explore Quantum Dot Based NVRAM 49 comments
I Don't Believe in Imaginary Property brings us an article describing the possibility of a new type of non-volatile storage based on quantum dot technology. So far, researchers in Germany have achieved 10ns access times and 0.7Hz refresh rates. Their calculations predict that the access time could be maintained for up to a million years. We have discussed other technologies based on quantum dots, such as solar panels and information teleportation. From the Ars Technica article:
"Quantum dots can do this because there is more design freedom in setting them up. Normal flash memory relies on the huge potential barrier created by a silicon oxide layer. However, to get electrons across that barrier when writing data to a flash cell requires a lot of energy, energy that destroys the silicon oxide layer. Quantum dots, in contrast, have tunable properties, so the barrier can be kept low."
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How much POWER will that take? (Score:3, Insightful)
"Teleporting one quantum dot will take 5 nuclear reactors", and such.
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I'll wait for the whole space folding / gate warping thing, where I can physically step from one spot to another (see: Stargate), thankyouverymuch.
Re:How much POWER will that take? (Score:4, Funny)
Whereas, the biggest difference between Star Trek and Stargate SG-1 is that Star Trek stole from westerns, and Stargate SG-1 stole from every sci-fi show that's ever been shown. (I'm not saying they did it badly, though.)
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Re:How much POWER will that take? (Score:5, Funny)
Are we talking about Africa or European reactors? And secondly how would two reactors carry the quantum dots? With a line or a strand of creeper?
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(oh, wait... only if it's encased in a Delorean)
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drat... iPhone is already obsolete (Score:2, Funny)
Biggest Hurdle (Score:5, Funny)
NOT a matter transporter (Score:5, Informative)
Re:NOT a matter transporter (Score:5, Informative)
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Re:NOT a matter transporter (Score:5, Funny)
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Isn't one of those quantum states made up of positions? If you aren't transmitting matter then clearly the position (and momentum) quantum states aren't being included. The only way of identifying identical particles is by their state. If all the states move from one, otherwise identical, particle to another, then the particle itself has moved. The only way you can say it hasn't, would, obviously, be if the position state of the particle hasn't changed. So all the other identifying properties of the particl
Re:NOT a matter transporter (Score:5, Interesting)
Now, as for actual matter transportation -- and particularly people -- I've always wondered exactly how that would work. I am not one of those morons who believes that we have a soul or some particular part of our body or supposed spirit that makes us who we are. So - does that mean that simply taking my precise atomic makeup at point A and re-assimiliating it with different atoms over at point B will result in a real, actual me? Or would it be me without whatever makes me myself? I mean, soul and spirit bullshit aside, how could every neuron firing in my brain and every receptor and every blood vessel and capilary and memory stored away in my brain ever be re-produced somewhere else? Surely with so many trillions or quadrillions of atoms that make me up, there will always be some loss. So when you transport me from home to the office, I am a lossy me.
And then, of course, the more you transport, the more you become like a photocopy of a photocopy of a photocopy of a photocopy. Or, if you like another analogy, you go from being Alec Baldwin to Stephen Baldwin to Daniel Baldwin to a pool of primordial goo.
I've also always wondered what would keep someone from just creating many copies of themselves. A transporter would never truly transport you. It would simply map your makeup here and assemble the same thing somewhere else. But that isn't to say that you'd have to destroy the version at point A from which the map came.
So at best, we might some day have matter duplicators. There is no way we would ever have matter *transporters*. If you are going to assemble an orange a mile away, why bother with the energy to destroy a perfectly good orange here, that the duplicate came from? And when it comes to people... can you possibly imagine the indescribable agony you would experience every time you went through the process? They'd confirm that your duplicate was assembled and functional at your destination... and then destroy you at your point of origin. You would somehow be taken apart at the atomic level. Perhaps reduced to a very fine recycleable dust. It wouldn't be harmless and fun like in Star Trek. It would probably be like having a trillion surgical scalpels cutting into you while every inch of your body inside and out felt like it was burning and being shredded and ripped apart.
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Unless there's some form of error correction, you're correct. You would be "faxing" your quantum information to another location which then is applied to matter. I suppose you could use two atomic clocks in sync to
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Re:NOT a matter transporter (Score:5, Informative)
Various fundamental results have already been formally proved about quantum physics. One of them is the no cloning theorem [wikipedia.org], and one of its many implications is that no duplication is ever possible: copying anything on a quantum level must always involve destroying the original.
Another proven result is the no teleportation theorem [wikipedia.org]. This one indicates that quantum matter teleporters are fundamentally impossible. It just can't be done. It's not a problem with scale or accuracy, you cannot even teleport a single atom.
These two theorems are not based on vague arguments, but on the mathematics underlying quantum physics. As such they are iron-clad.
If either a working duplicator or teleporter is ever built, we already know that it will not be based on quantum physics, but on some lower level of physics that has not yet been discovered. This is unlikely to happen in our lifetimes (it takes roughly 100-200 years to move from one level of physics to the next, based on history).
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Re:NOT a matter transporter (Score:4, Interesting)
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It won't work for communication... (Score:3, Funny)
Speed? (Score:2, Interesting)
Re:Speed? (Score:4, Interesting)
It's not measurable (really! to measure it would require a system that can transport information faster than light, and that's not possible so far as we know) and not really important. You teleport an entangled blob of quantum state, which arrives "almost instantaneously". You cannot do anything with it until you receive the companion classical information from the transmitter, which you need to "unpack" that blob of quantum state and extract the teleported information from it. The effective speed of the process is precisely the same as the actual speed of your classical (non-quantum) slower-than-light information channel, and that's the important part.
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Quantum teleportation requires the transmission of classical information before the "teleportation" can be completed, and the transmission of this classical information is done by conventional means which are limited to the speed of light. For some reason there seems to be a popular and often repeated misconception that quantum teleportation is instant
quantum dots (Score:2)
And I don't mean Star Trek or cell phone jokes. I don't mean jokes at all (which I suspect will constitute 99% of the posts over here).
This article in fact doesn't have anything to do with the audience here, except that it's about (drum rolls) magical teleportation. Which won't happen probably in the next 50-60 years, yet we get teleportation articles over her
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You could use it to make a Beowulf cluster of quantum computers.
(I kid you not.)
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If these particles can actually travel faster than the speed of light...does that mean they may be from "another dimension in another 'time'" where our physical laws don't apply or being sent by other scientists doing the same experiment only in reverse from this other "place"???
Well, thanks for confirming my original point...
Read the discussion... (Score:5, Informative)
Teleporter death (Score:4, Interesting)
From the sounds of TFA, the new "you" would not actually be you at all, just a copy. It sounds like your conscious mind would be obliterated and a new one created, although the new one might not be aware of it.
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If you weren't aware of it, and you kept your previous consious state, would it even matter?
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Okay, so they say that there's a "new" you at the destination, but the old you dies, right? You die.
Would you bet your life on the process "keep[ing] your previous cons[c]ious state"?
Re:Teleporter death (Score:5, Insightful)
"Just" philosophy (as you so eloquently put it) is not at all "meaningless and essentially useless", and quite a few answers can and have been found through philosophy.
However, the questions that are asked in philosophy cannot usually be answered empirically. Neither by observation or experiment, nor by reference to faith or revelation, but rely instead wholly on reason. This should not be taken as evidence that the questions cannot be answered. Logic, for instance, is based purely on reason and it springs, as do so many other fields of study, from philosophy. It also answers a lot of questions.
In fact most of what we now call science was at one time or other found under the heading "philosophy", and only with advances in philosophy did it spring forward as a science in it's own right.
So you see, far from being meaningless and essentially useless, philosophy is in fact inherently meaningful and useful as a tool to explore areas of knowledge science does not yet have the ability to tread. For instance, the philosophy of mind to which this discussion pertains.
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Re:Teleporter death (Score:5, Insightful)
Let me ask you a question. Isn't it true that your cells are constantly regenerating themselves? The matter you were made up of when you were born no longer is the same matter, but you are still you. So if your qunatum state was duplicated and during the process the original was destroyed then you would still think you are you. Would you still BE you? That just opens a whole can of worms.
The question in my mind is can quantum teleportation bring along your soul? If you don't believe in a soul you have to ask yourself a couple of questions. Are you only you because of that matter that makes you up? The matter that makes you up comes from the stuff you eat. So is the stuff you eat part of you before you eat it? Is it only you when you make food part of your cells and your body? What makes you unconfortable with the idea of your body being made up of different energy? Consider this: Your body is constantly rebuilding itself with new and different energy and disposing of the old parts. Whats the difference?
I bet most people wouldn't step into a teleportation unless the quantum state of your atoms were reconstructed with the SAME energy.
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Not quite. With teleportation you cease to exist where you were because your body is destroyed and rebuilt with new matter so that you can exist where you are now. Not as trivial as "walk[ing] through space", is it?
You might be on to something with the next paragraph though, people usually have a hard enough time getting to grips with the fact that a future me or a past me is somehow still me. Now try and make them see
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I'd argue the answer is no, but it is, as you point out, an existential problem. For many people there is a qualitative difference between the slow regenerati
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Quantum dots (Score:2, Funny)
Couldn't time delay be the form of communication (Score:3, Interesting)
Let us take 9 "quantum pairs" (honestly, I don't know the exact terminology of them). You have 9 of them on Earth (A) and 9 of them elsewhere (B). They are ordered from 0 to 8. Assuming that you can determine when the quantum waveform collapses into spin up or spin down, you start the communication when A0 is caused to collapse. Instantly B0 becomes up or down. That's the start of the communication. If after 1 ms, B1 is found to have collapsed into an up or down, that counts as a 0. If after 2ms, B1 is found to have collapsed into a up or down, that counts as a 1. You would be able to generate a byte of data this way.
So start-2-1-2-1-1-1-2-1, would be 10100010.
The point is that it doesn't matter whatever B0 to B8 end up as. Just when they end up as an up or a down.
Are you going to be able to determine whether the waveform has collapsed without collapsing it yourself.
Of course, I didn't sleep last night. My guess is that if you are in a position to determine whether or not the waveform has collapsed, you will collapse it yourself. Maybe there's an indirect method.
As far as matter transportation, I wouldn't rule it out as impossible. I certainly wouldn't say it's inevitable. When quantum communication is studied in greater depth, some inconsistencies may be uncovered which could lead to a "greater truth".
Faulty assumption (Score:5, Informative)
This is the faulty assumption.
Think of of entanglement this way. You have two roulette wheels and they are "entangled". What this means to the roulette wheels is that they are spinning and the marbles are bouncing along inside them synchronously(I know they'd be at right angles but being the same value works well for the visualization). So you split them up and one roulette wheel is in another galaxy and the other is here. Both are spinning and the marbles are still bouncing around in sync. If you stop one, the other keeps going. If you stop them at the same time the marbles will have the same value. But the problem is the one you assume away. You cannot tell that the other roulette wheel has stopped.
In QE, if you attempt to observe the entanglement, you make it collapse. You can't tell what the state of the particle is without destroying the entanglement.
IINAQP and I could be wrong. But this is my understanding and my cousin who is a Physicist tells me I have an accurate, if rudimentary, understanding of this particular phenomenon.
I wish you were right.
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No Communication Theorem (Score:2)
If you have a set of atoms on earth, and an equivalent set of atoms on say Mars (light minutes away), synced with teleportation - any message sent from earth would be received on Mars faster than the speed of light, but when observed the message would inherently be garbled to the point where it could not be understood due t
Model teleportation system (Score:3, Funny)
Re:Cool. (Score:5, Informative)
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Re:Cool. (Score:5, Funny)
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Re:A little confused... (Score:5, Informative)
It cannot transmit information faster than the speed of light. It can transmit information when combined with a classical, slower-than-light transfer. It cannot transmit any information without having a classical (non-quantum) information transfer also take place, so the speed is limited by the speed of the classical transfer.
As you would expect, the utility of this is somewhat limited.
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But how much will transportation affect the economy? So many jobs hinge on transporting people and goods. As well as those that service the cars, trucks, trains and planes. That many people out of work would definitely have a major impact.
You are falling for the broken window fallacy. Ignoring any shortterm/disruptive effects, and one-off costs in retraining, everyone would get richer, as the manufacturing price for many goods and editables would decline due to cheaper and faster transportation. The money people saves by not having to pay (as much) for transportation would be used elsewhere, and that elsewhere would need more people to do it.
This is all assuming that this is at all feasible, which I doubt.
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Probably more likely that data will just turn up without asking, closely followed by a bill from some company you have never heard of demanding a fee for the 'subscription' to a quantum directory they claim will appear in over 250,000 businesses in your area.
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I think the confusion perhaps relates to the difference between quantum tunneling (where "almost instantaneous" shows up) and any attempt to use quantum tunneling for the purposes of information transfer.
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An experiment of theirs, where a single photon tunnelled through a barrier and its tunneling speed (not a signal speed!) was 1.7 times light speed, is described in
* Steinberg, A.M., Kwiat, P.G. & R.Y. Chiao 1993: "Measurement of the Single-Photon Tunneling Time" in Physical Review Letter 71, S. 708--711 "
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Some of our routine surgeri