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Breakthrough Brings Star Trek Transporter Closer
japerr writes to mention The Independant is reporting that a new breakthrough may bring scientists one step closer to a Star Trek style transporter. " A team of physicists has teleported data over a distance of 89 miles from the Canary Island of La Palma to the neighbouring island of Tenerife, which is 10 times further than the previous attempt at teleportation through free space. The scientists did it by exploiting the "spooky" and virtually unfathomable field of quantum entanglement - when the state of matter rather than matter itself is sent from one place to another. Tiny packets or particles of light, photons, were used to teleport information between telescopes on the two islands. The photons did it by quantum entanglement and scientists hope it will form the basis of a way of sending encrypted data."
A lovely headline, but the only practical application of this form of "teleportation" is cryptography (you could have some pretty damn unbreakable keys with this). Even if you could "teleport" any significant amount of matter, it would be many, many, many orders of magnitude more challenging than this and you would have to get past some pretty significant hurdles (Heisenberg being one of the least of your problems).
SJW: Someone who has run out of real oppression, and has to fake it.
Sure they have. That's why all the Star Trek transporters employ "Heisenberg compensators". Duh.
I read Usenet for the articles.
you missed the part about quantum entanglement, which is not simply fiber optics. Niels Bohr is rolling in his grave right now.
The creator of this post (Jacob Smith) hereby releases it, and all of his other posts, into the public domain.
TFA mixed up both the author's name and the journal this work was published in. The author's real name is Rupert Ursin (not Robert), and the article was published in Nature Physics Online, not Nature Physics (those are separate journals). The article itself is available here as a pdf.
It is teleportation of information, not of matter. We scientists define teleportaion as "moving something between point A and point B without ever being in between", which is different from the Star Trek "transforming matter in energy and into matter again". It does get us a whole lot more funding than if we had called it something unfashionable like "Communication through entanglement".
By the way, IAAT (I am a teleporter). I don't get to work work in the Canaries though. It's a shame.
We can already transport data through space without using quantum entanglement at all -- it's called radio.
The key difference is that quantum teleportation can transmit data at speeds faster than the speed of light.
I think a lot of the verbiage used to talk about quantum physics/quantum computation is misleading and was poorly chosen. There is no reason to call it "teleportation" when they're only sending data and not matter. And there's certainly no reason to keep quoting Einstein's "spooky" for any of these summaries. It's all just BS that detracts from the actual science, which is pretty interesting as long as you don't come into the study of it expecting to find Star Trek-type teleporters.
"Choosing to refrain from producing another person demonstrates a profound love for all life" [vhemt.org]
Read the paper here!
The ansible communicated by means of two entangled particles. That is impossible by everything that we currently know.
The type of system they're talking about is where you use entangling to imprint the differences between two particles on a third one. They're fundamentally different and resemble neither the ansible nor star trek transporters.
Oops, my fault entirely for not reading what I was posting properly. Yes, essentially, what these people have done is what the article I linked to (published only a few weeks ago) said was impossible. That's science for ya.
(of course, INAP either, so maybe I still have it wrong, stranger things have happened..)
The creator of this post (Jacob Smith) hereby releases it, and all of his other posts, into the public domain.
if you're trying to send data, you'll still need to send photons (or other particles) from one location to another. when you're talking about quantum entanglement and sending data across distances, what you're doing is taking two photons in the same location and tieing them together, then sending one of the particles across a distance. when it gets there, it's still tied together (unless something screwed it up on the way), but if you try to manipulate your photon then it unties from the other, so you cant use it to send info faster than light.
Well, a google search for "the independant" changes all the options to "independent" and http://theindependant.com/ looks like a news site but it's just a parked domain. So yeah, it may be a typo.
The Group of Applied Physics at the university of Geneva, Switzerland is playing with quantum teleportation for some time already, visit
http://www.gap-optique.unige.ch/ for more information.
A spin-off also sells products based on this technology:
http://www.idquantique.com/
Derek Parfit is an interesting philosopher who's done a lot of work on personal identity just by examining various Star Trek transporter scenarios (like what if you're reconstructed at the other end but don't disappear at the start).
Anyone who loves or hates any language, platform, or manufacturer, doesn't know what they're talking about.
Now, that doesn't mean that you can't create multiple copies of the same known state. In fact physicists do this all the time to run experiments enough time to obtain statistically reliable results.
But it's also not the same thing as entangled particles. Entangled particles are not identical, in fact most of the time they've got different qualities like polarization. I've got another post in this topic that I believe sums the issue up fairly concisely.
The gist of the argument is that special relativity divides the universe into three regions of spacetime: the timelike future (which is the set of all points where you COULD be in the future if you could travel at any speed up to and including the speed of light), the timelike past (which is where all events that could POSSIBLY have an affect on you at the present reside) and "elsewhere", which is comprised of all other events. An example of an "elsewhere" event is the state of the Mars rovers RIGHT NOW. I can't possibly know that at the moment because there's about a 30 minute light travel time delay. It's important to realize that FTL communication connects you to an event in "elsewhere" in a causal manner.
If you draw a spacetime diagram for two people, one of whom is moving very fast (at a conventional sublight speed) relative to the other, you'll find that the "elsewhere" of one observer intersects the past of the other. So using FTL communication and sublight engines to send a message to the past would work like this:
1. Bob gets in his fancy spaceship and travels directly away from earth at 90% the speed of light. He travels for 1 year (the time and speed aren't really important, they just allow the message to be sent farther into the past).
2. Alice, on earth, sends Bob an instantaneous message using her FTL communication device. It travels to Bob along what Alice considers to be her "line of simultaneous events" - the line in her spacetime diagram that goes through her present position and on through "elsewhere", to define the "present". It's not necessary for Alice's communication to be instantaneous, but it makes the argument (a little) clearer and doesn't really matter because going 1.0000001x the speed of light is just as impossible as going infinitely fast (as an instantaneous communication device would have to do).
3. Bob receives the message at the exact instant (in Alice's timeframe) as when she sent it. He then sends the message back to Alice using the same FTL device. The difference is that Bob is travelling at 90% of the speed of light, so his "line of simultaneous events" is completely different- it actually intersects Alice's "timelike past".
All of this makes a lot more sense once you get the hang of drawing spacetime diagrams, but it confused me for many years. You might want to google for tutorials on spacetime diagrams or "pole and barn" paradoxes to see some examples of spacetime diagrams...
As I recall, the dilithium crystals were not the source of energy; they were merely there to regulate the matter-antimatter reaction. As far as I know the origin of the antimatter was never explained. Forget dilithium; if we had their (presumably unlimited) supply of antimatter, energy would become the least of our worries.
"The state is that great fiction by which everyone tries to live at the expense of everyone else." - Bastiat
Interestingly it's not really hard to see that there's no superluminal information transfer. All you have to do is to look at the system in the Heisenberg picture. See http://arxiv.org/abs/quant-ph/9906007 for details.
The Tao of math: The numbers you can count are not the real numbers.
Sorry to nit, but since we are flexing our geek muscles here (the only muscles I have), Data has actually used contractions on occasion. According to Memory Alpha, "...Data also had trouble using contractions in regular speech although this was part of his programming by Dr. Soong." So apparently, it was possible for Data to use contractions, but not without difficulty and, therefore, rarity.
-- My hovercraft is full of eels.
"and the reassembled matter was actually the same physical matter that was disassembled, not just a copy of it."
e pisode)
http://en.wikipedia.org/wiki/Second_Chances_(TNG_
Patrick Van Esch explains it much better than I can:
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
no, you actually have to send a photon. you can create entanglement at a distance. you create it locally, then send the photon.
Mo, you ARE sending photons. You have 3 photons involved. 1 and 2 which are entangled and seperated by a distance. 3 interacts with 1 then is transmitted to 2 and then interacts with 2 in a way which preserves the original entanglement plus the changes incurred through interaction with 3. Thus transmitting the changes of interacting with 3 from 1 to 2.
You are still left with having to transmit photon #3.
Wrong. Completely and utterly wrong. You can't send information faster than the speed of light.
Quantum teleportation doesn't work like that. Here's basically how it works: Two quantum particles are entangled. Then they are separated from each other, one goes to point A the other to B. If you do a measurement on A and COMMUNICATE THE RESULT OF THAT MEASUREMENT to where B is. The other guy can do a special measurement on B based on what A's result was. Then the state of A becomes what the state of B was originally. The particles have not moved (the measurements have changed their states, though), but A's state has been "teleported" to B. It's all to do with the fact that the two particles were entangled in the first place.
But the very important point is that you *still have communicate the result of the first measurement*, which means you're limited to the speed of light.
There is still application for encryption since just knowing what the result of the measurement was is not enough without having the actual entangled particle B.
BUT THERE IS NO APPLICATION TO STAR TREK-LIKE TELEPORTATION OR FASTER THAN LIGHT-SPEED COMMUNICATION. And frankly I'm getting tired of seeing the same wrong information getting played in the media like this. And slashdot even, come on guys, you should know better by now. I'm new here, aren't I?
Yes, IAAQP.
>> You can't send information faster than the speed of light.
Correction: You can't send information faster than the speed of light in current models.
Science is about devising consistent mathematical models, using them to create hypotheses that should be observable in reality, and then determining the degree of correlation between the prediction and the observed behaviour of reality. If the correlation is good then the model is considered useful. That's it, that's all there is to the scientific method.
Our current scientific models say that you can't send information faster than the speed of light, and that's an inescapable property of these models, built into their mathematical basis, but it is not a property of reality herself. We have no means of knowing what reality will or will not permit. We'll need to devise new models in order to test deeper properties, as it's beyond the capability of current models.
Don't confuse models with reality, nor properties of models with properties of reality. The two are quite distinct.
The above explained crudely and innacurately using ascii diagrams.
/Y/ has been traveling rapidly to the /right/. As such, only half of half an hour has passed for her, and her watch says 9:15.
X and Y are at the same location. It is 9 o'clock
XY
9
X has a sudden, irresistable urge to get as far away from Y as possible. He departs rapidly to the left at Mystery Speed(tm)
X {- Y
Y's Tale
Y stands around for an hour, at which point she feels needy and clingy and rings him with her Nifty Ansible(tm). Her watch says it is 10 o'clock.
Now, from Y's perspective, X has been travelling so fast to the left that he has reached relativistic speeds. As such, only half as much time has passed for him. His watch says it is 9:30.
X {- Y
9:30 10
He gets a phonecall. Y says "I miss you I need you come back (bring me a magazine)"
He replies "Fine." and hangs up.
X's Tale.
X realise he didn't know which of the seventy million identical celebrity magazines Y wanted. But from X's perspective,
X -} Y
9:30 9:15
She gets a phonecall. X says "What magazine do you want?". Y says "OMG YAY YOU WERE THINKING OF ME a people would be nice."
Y, having gotten the reply 45 minutes before she sent the initial call, thinks X called off his own bat. She feels happy and validated, and does not ring him 45 minutes later. So he never calls her. So she feels lonely and calls him. So he calls. So she doesn't. So he doesn't. Then the universe explodes.
X BOOM Y
And that's why relativity and relationships don't mix.
the state of the second particle doesnt change. period.
there is 1 wave function. you're not observing one of the particles, you're collapsing the wave function.
when you first entangled the two particles, you made it so that they both had to have the same property. and you sent one of the particles to your buddy. because you were careful about sending it, and making sure it didnt bump anything else, you know that they still have to have the same property. you dont know what that property is yet, because you havent looked. then, you look.
this is exactly like taking two balls, a red and blue one. you mix them up and mail one to your buddy, without looking at either one. you know that if you look at yours and it's red, then your buddy's must be blue. but you havent looked yet.
now stop. dont think ahead. the two situations are exactly the same. now move ahead, and everytime you find yourself wondering how the first particle affects the second, remember the red and blue balls.