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Quantum Dots Might Be Key For Teleportation
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.'"
Cool, but all this quantum shit makes no sense to me.
Quantum computing... quantum encryption... quantum dots...
I've really tried to labor through the explainations but I guess I'm just not close enough to quantum physics and college math. I'm otherwise generally pretty good at understanding these technical explainations, but quantum just sounds like another buzz word, and one that goes over my head.
Please tell me I'm wrong. Tell me Quantum isn't another cyber, blog, or pod! I really want to be wrong because the implications of these advances sound pretty cool.
Measured in nuclear reactors, I mean.
"Teleporting one quantum dot will take 5 nuclear reactors", and such.
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Drat. iPhone is obsolete and it doesn't even go on sale until Friday. This whole quantum dot thing will make 3G networks obsolete before AT&T even gets it rolled out here in the U.S. I want my "iPhone Quantum". : )
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Biggest Hurdle so far is figuring out how to stop the quantum pac-man who keeps eating them.
Quantum entanglement is a great way to get information from one location to another at faster than the speed of light but offers no way to transmit matter. Theoretically the precesses here allow for technology like the ansible from Card's Ender's Game series but won't be transmitting ensign Ricky to his death from aboard the starship enterprise. Now, if we were all information-based entities teleporting about using quantum entanglement would be highly feasible.
"Almost instantaneously" seems to be another way of saying "not instantaneously", which we could have guessed anyway. So why not say how fast it actually is?
Ok, I want to hear from a single guy in this forum/site, who can take this "teleportation might use quantum dots" information and make some use of it.
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 here every few days as if on schedule.
There are so many things happening right now we COULD make use of to further our knowledge, which we possibly comprehend:
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The article is pretty light on information, but hte discussion has a pretty thorough description of why this can't (AFAIK) be used to send information, including a link to the wikipedia topic. Maybe they have a way round that, but you can't tell from the article.
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This reminds me of a question I never found the answer to: if you teleported yourself, would you die and a clone be made?
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.
const int one = 65536; (Silvermoon, Texture.cs)
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I wonder how long until I am getting a bill from a 'Quantum Dot Provider' that pipes these things in over a special line in my house to fill my computer, which keeps emtpying out because of decoherence... "Honey, do you have that spare packet of Quantum Dots for the computer? I think I put mine through the wash..."
If the only way you can accept an assertion is by faith, then you are conceding that it can't be taken on its own merits
While the article may not be information rich, the interest of this is rather significant. Communication between two points simultaniously no matter how far apart they be, would greatly increase information reliability of probes we send into space, as well as in the far far future allow us to have probes send us information from the edges of Black Hole event horizons. It is nice to see forward thinkers, but I wish they would have provided us with slightly more information.
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.
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.
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".
IANAP(hysicist), but it is my lamens understanding that the No Communication Theorem is such that the act of observation lies in direct contradiction with the potential for communication.
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 to the fact that the observation of said atoms would disturb their state.
Somebody please correct me if I have misinterpreted.
This is certainly a great feat - displaying the capabilities of teleportation, but it is not the only mountain to climb. I do not read that they have resolved the issue of observational mish-mashing, but one could deduct that they did at least to a degree in order to prove that the teleportation happened - although they probably used a known quantum teleportation scheme which would involve additionally a classical information transportation method and thus limiting teleportation communication by the limits of that already existing information transportation methodology. (still pretty neat, but not necessarily groundbreaking as experimentation on this level has been happening since roughly 1998)
It's not that difficult to come up with a potential list of ways to resolve this problem, finding a solution that actually is provable certainly would be difficult. If in fact they have surmised a way to communicate via teleportation rather than just prove that teleportation is possible an entire world of possibilities just opened up that will take us centuries to truly realize.
Assuming that you can determine when the quantum waveform collapses
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.
Quantum teleportation is nothing more than the equivalent of the MOV instruction on a quantum computer, with the oddity that this instruction actually does *move* the data, rather than copying it. As you can imagine, this is one of those basic instructions that you have to be able to implement properly in order to be able to have a quantum computer, which is why people are trying to get it right.
The reason it's called "teleportation" is just to emphasize that the data was once in one place and now is in another, in contrast to classical data which you can copy and so have in two places at once.
As for why you have to teleport the data, the answer is (very, very roughly) that if you were to copy the data then you would be overwriting a register somewhere, which destroys the data at that register; this is not allowed since you cannot destroy information in quantum mechanics. Put another way, you should always be able to construct any arbitrary past state of the universe given the present state; if you were allowed to overwrite a register with a new value, then you would lose the ability to figure out what value it had in the past, ergo copying is not allowed. (The more precise statement of this fact is the so-called "No-cloning Theorem".)
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I don't know that the Offtopic mod was all that fair on this post. Sure, it lacked a little detail, but what's with this "almost instantaneously" bullshit that keeps coming up every time we talk about teleportation?
Maybe it's plausible in a Star Trek universe, but in our universe, we appear to be constrained by the speed of light, even for transmitting information through entanglement. Sure, one might argue that speed of light is instantaneous, but we all know that this kind of language gets a bunch of readers' hopes up every time.
Maybe you could elaborate.... I understand that the entangled particle has to be moved to a new location once at no faster than the speed of light, but after that one time what is to prevent communication between those two locations at faster than light speeds?
At least not until we figure out how to use quantum DASHES along with the quantum dots.
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The fact that you cannot predict to which state the waveform will collapse when you measure it. Yes, after the interaction, both Alice's and Bob's particle will be in the same state but since Alice did not choose that state, she did not transmit any information to Bob. Only by using a separate, classical information channel can she inform Bob whether this was the intended state or not.
Also note that transmitting information superluminally would effectively be sending messages into the past. This violates causality.
I have also wondered whether detecting the timing of waveform collapse provides a loophole to the "No FTL communication" rule. Since quantum calculation relies on having an un-collapsed waveform, Bob could attempt a calculation, and if it fails then he knows that Alice alreadly collapsed his waveform. Ta-Daa! FTL communication. Interestingly, google gives zero hits for "detect waveform collapse", "detect quantum waveform collapse", "detect whether waveform collapsed" and a few other variants.
reading http://en.wikipedia.org/wiki/Quantum_teleportation makes it clear that this isnt "teleportaion" as you would think about it. you can't use it for transportation or anything.
the way it basically works is that say 2 people have an entangled pair of qubits. then person A who wants to send some quantum state to person B measures his qubit which then collapses into some random state. person A, now knows the state of person B's qubit because they are entangled and sends some information to person B (classically, by, say, telephone or whatever) that tells person B what operation to perform on his qubit to turn it into the state that he wanted to send.
so the best this can be used for, as far as i can see, is transmitting a huge amount of information but only having to send very small amount through 'classical' channels.
Wouldn't that be useful for unlimited internet connection? like, EVERYWHERE and unlimited bandwidth?
"Also note that transmitting information superluminally would effectively be sending messages into the past. This violates causality."
Funny, I don't recall ever going over the "universal law against killing your grandparents before you're born" in any of my physics classes (but I only took 17 of them). This "law" of causality is an assumption; the universal speed limit appears to be the reason why causality remains intact, but "it violates causality" is an empty statement. As long as matter/energy isn't being created/destroyed in the process, and you're not going faster than c, the universe doesn't really care about your grandparents' past well-being.
Throw more dots, more dots, more dots ... Ok, stop dots.
Isn't that the "ice cream of the future" you see advertised all over the place? Just asking.
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The fact that nothing you do to the one part of the particle can directly influence any measurement outcome on the other side. You need additional (classical) information from the sending side in order to distinguish any measurement results from completely random garbage. One way to think of it is to think of the quantum information as encrypted by an automatically generated one-time pad during transmission, and you cannot read it until you get the pad, which is only revealed to the sender and thus has to be transmitted classically.
The Tao of math: The numbers you can count are not the real numbers.
In Soviet Russia, quantum dots teleport YOU ... oh wait, that wasn't Soviet Russia, it was USS Enterprise. And it wasn't quantum dots, but Scotty. And it also wasn't YOU, but Captain Kirk. But except for those unimportant details, it's correct! :-)
The Tao of math: The numbers you can count are not the real numbers.
They made a model teleportation system. Why do models get special treatment? I can undestand their being able to deduct makeup as a business expense, but why do they get a teleportation system first?
...teleportation will bring privacy concerns...
One of these days maybe I will learn to quit having a beverage available while reading /.
:-)
This is another of those times...cleaning up spewed coffee (black-no sugar) IS a little better than the beer in the keyboard and all over the monitor!
But at least I'm still chuckling as I cleanup!
Thanks for a good laugh to start the day with.
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Parent is redundant, the moderator probably just didn't get it. It's funny for the obscure Space Balls reference (except that correct the quote is actually "Why didn't [anyone] tell me my ass was so big!?".)
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You are making a great "step" to hide a flaw in your reasonement. The difference is that the body is not destroyed and rebuilt each instant. It only very small parts which die off and are replaced. But not identically else you would neither grow, nor would you forget, nor would your body differentiate during foetus growth. I repeat the MAIN mass of the body and brain is NOT replaced at each and very instant even if it is over time. This enorm step you take is assuming a Destruction of the whole body, then at a LATER time reconstruction would be identical to the small replacement which occurs constantly in the body. But it is not. It is NOT a philosophical question. At the moemtn you destroy the body for the teleportation, the life is OVER for this individual. Maybe an identical 1:1 individual is reconstructed with the same memory but it was not the original one. The perception for this individual would be final : death. Pretending otherwise introduce another entity which is the soul (or whetever you want to call the entity holding all info of the individual while his brain and body are non existent and destroyed), the only way to maintain that the individual survive the destruction to be reconstructed. But up to now there is no scientific proof of soul existing, and many evidence that the brain alone and its structure is responsible for our "self". Destroye the brain and everything is gone, even if you make a second one identical in any point. And if you really want to bring soul in the debate, then please feel free to bring evidence. But be warry that extraordinary claim, require extraordinary evidence.
even worst, if you can measure all atom, position, and quantum state and somehow reconstruct an individual at another place, then there is no obstacle to make multiple copy. If this is the case, then no one can pretend the original did not die and both copy are not the original.
Bottom line: if ever teleportation come to be in reality and is not science fiction, the only way to put me in a teleporter would be to shoot me dead and send my meat to the other side.
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So if communication via entangled quarks is impossible (ref: the forum comments in TFA), and seems to be impossible because passing information instantaneously (i.e., faster than the speed of light) is thwarted by the quantum states being "a jump ahead" of free will and conscious action, adjusting themselves to compensate for the actions of supposed free will -- does this mean that free will is an illusion?
That we are steered by the manipulations of quantum states, and have no real say in what we do?
Do we live in a Clockwork Reality, something akin to Stephen Wolfram's automaton theories of reality, where a set of rules generate the next state of Reality from the current state?
Easy suicide!
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
"...but what's with this "almost instantaneously" bullshit that keeps coming up every time we talk about teleportation?"
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.
Wasn't that was one of the problems einstein had and could never get to the bottom of was the spooky action at distance? Where effects of quantum entanglement do travel faster than the speed of light. Various theories have come along to explain it, including faster than light particles which travel between the two entangled particles effectively going back in time and setting the observed property when the two were in close proximity.
In theory it is possible to travel faster than light, the theory of relativity is symetrical around the speed of light. But it is impossible for any particle to go across the light barrier, either slow down under it or speed up over it.
It may be impossible to implement (currently) like many things in theoretical physics, but so were so many things we take for granted now a century ago.
"The Berkeley group:
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 "
I tend to think that when something is too good to be true, it probably is. Quantum entanglement is most probably a result of an error in the physics model and likely doesn't exist in reality.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Teleportation is only limited by your imagination...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
"Are you only you because of that matter that makes you up?"
Is a sound only that sound because of the matter that makes it up?
It sounds like you are basing your argument (and the other one earlier in the thread) on the "What the (bleep) do we know?" movies. You would be doing yourself a favour to read critiques of them and see that while there is a bit of actual science present, for the most part they're very inaccurate and heavily padded with wacky cult nonsense.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
Here's the referenced article, outside the PhysOrg tarpit. Abstract only without a paid subscription.
And it only transports matter!?
The thing in the box has no place in the language-game at all; not even as a something; for the box might even be empty.
Teleportation is absurd -now-. 150 years ago, magic picture boxes were absurd. 150 years before that, a magic box that could transmit sound near instantaneously from place to place was absurd. How about taking someone's heart out, putting a new one in, and having that person not die from it? Allowing blacks and women to vote? The very concept of a man controlling billions of dollars? The only true absurdity to be found is the certainty that things will always be as they are.
Some of our routine surgeries would have been called vivisection. Many of our standard technologies would be called witchcraft. And when the rules said no to cruel and unusual punishment, that meant that we wouldn't be burned at the stake.
I see your informative link, and raise you a pithy comment.
Maybe it's plausible in a Star Trek universe, but in our universe, we appear to be constrained by the speed of light, even for transmitting information through entanglement. Sure, one might argue that speed of light is instantaneous, but we all know that this kind of language gets a bunch of readers' hopes up every time. Sir, you asume its about human teleportation. Yes, if it where the case, i'd classify it as bull also.
TFA however only mentions a quantumdot.
About the speed of light: (SoL) It is relative.
If i where to travel at 0,5*SoL, and would throw forward a baseball at 0,3*SoL, the light reflected of the baseball would travel at 1,8*SoL.
And beyond that simple equation, quantum mechanics have displayed some weird time properties!
Note the term instantaneous is very open for discussion.
The definition of "instantaneous" is relative. Adding "almost" makes it an relative aproximate.
Seen in a 10.000 year timeframe, taking the bus to the next country would seem almost instantaneous.
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Don't bother beaming me up Scotty, there actually IS intelligent life out there!
Read my post again. I never said it was a law. I only stated that causality would be violated by superluminal information transfer. Insofar, causality has had the trend of not being violated. While this does not even hint that it is a law, it does tell us taht it doesn't get violated very easily. However, even this is more than what I meant to imply with that statement. I was merely explicitly pointing out that superluminal information transfer would violate causality because it is not an obvious consequence to someone who is not familiar with physics. Nothing and more and nothing less. My choice of words was probably not the happiest solution for expressing this, though.
As a part of the project in my junior year, I feel extremely elated to see it on the frontpage of slashdot.
We have 2 cases: a) the universe is deterministic, b) the universe is not deterministic (this one is favored by quantum mechanics).
In case a), the decisions you make are already predetermined by the paths of particles. No free will there, and an entity which knows the exact initial state of the universe can predict its outcome.
In case b), the world is truly random, it can not be predicted. Therefore, any decision you make, is the outcome of random processes. No free will there, as well: the universe drives your decision making process, albeit in a random way.
"Randon information" is not information. Randomness is better thought of as "anti-information". Information is present only as a deviation from perfect randomness.
No we aren't talking about information traveling faster than the speed of light. We don't exist in that way.
The physics term is "on-shell" (and i's antonym is "off-shell"). The idea is that quantum mechanically, there can be a lot more going on than in classical systems. A common example of this is vibration modes of a photon. Classically, they can only vibrate transverse to the direction of propagation (as I understand it, this can be thought of as due to the photon travelling at the speed of light). However, in QM systems, one finds that between classical observations of the system, one has to consider virtual photons that can vibrate in the two other possible modes (longitude and compression IIRC). Since we observe things classically, we don't see off-shell dynamics like virtual photons.
Figuring out how to get space-time coordinates from more basic principles is one of the great unsolved problems in modern physics. There has to be some structure present even on these scales that extends to the concepts like distance, time, and velocity that we are familiar with.
They get to use the teleportation system first, cause they wear the sexy outfits the Captain likes!
I only look human.
My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
I would call my new world, the DOT MATRIX!
I only look human.
My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
Believe it or not, the answer is in this movie:The Prestige (2006)
http://imdb.com/title/tt0482571/plotsummary
The movie ends up revolving around a trick is called "the moving man" where the magician disappears and reappears 100ft away in an instant. The trick uses a device created by Tesla. If I say more, I'll spoil the movie for you.
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I think the really exciting part about all this teleportation speculation is that as Human Beings move ever closer to creating a matter teleportation device, we become closer to discovering the answers to questions such as "What makes me me?" and "Do I have a soul?".
These are questions that philosophers have been asking for thousands of years, and yet empirical science has failed to come up with any satisfactory answers. Will we ever make a functional teleporter? Who knows, and who cares? I'm sure that we'll learn a lot about ourselves and the universe we live in trying.
p.s. Apparently KFC's got Soul.
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So could you send a CRC value through a classical channel, and gobs of data through teleportation? Overall, the data wouldn't travel faster than light, but the net effect on transfer speeds would be astounding.
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I was under the impression that that the universal "now" is an obsolete concept.
Someone finally managed to post an article about quantum entanglement information transfer without cramming crap about matter transporters into it. They should get a reward. Of course that didn't keep people from making it their point of discussion. But then this is Slashdot, not PhysOrg.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
connect the fatom dots !!!
Well go print it on a mug or something. The article doesn't suggest anything will be happening instantaneously (nor have any so far) - it's only the Slashdot summaries and comments that get this crucial detail wrong. Until our understanding changes, I'd prefer we just stick to the facts as we understand them.