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Teleportation Gets a Boost
saavyone writes to tell us Yahoo! News is reporting that while teleportation may not quite be a reality yet a team of Danish scientists have raised the bar on this line of research. From the article: "The experiment involved for the first time a macroscopic atomic object containing thousands of billions of atoms. They also teleported the information a distance of half a meter but believe it can be extended further. 'Teleportation between two single atoms had been done two years ago by two teams but this was done at a distance of a fraction of a millimeter,' Polzik, of the Danish National Research Foundation Center for Quantum Optics, explained. 'Our method allows teleportation to be taken over longer distances because it involves light as the carrier of entanglement,' he added."
now beam down my clothes!!!!!!!
This process allows you to copy quantum information from one set of atoms to another without measuring it, and thereby destroying it.
It's still isn't anywhere near dematerializing the matter and poof`ing it across the room/planet. However, what is happening is the quantum information (in this case, the spin state) of the matter has been instantly transported. That is a essential step in building a quantum computer or cryptography network.
...that nerds will stop at NOTHING to prove Star Trek is real. First, transparent aluminum, now this.
blah blah blah
A technical explanation would take too long and people would just argue with me anyways so heres a summary -This is not 'traditional' teleportation -It works at the speed of light, there's nothing strange going on here, although it is related to what you might have heard referred to as 'spooky action at a distance' With quantum teleportation you aren't teleporting a THING, you're teleporting a property of that thing without actually measuring that property. Sounds crazy but here's an example: suppose you have two helium atoms and using light you are somehow able to give the second atom the momentum and spin of the first atom but in the process you change the momentum/spin of the first atom. You've basically changed the second atom to be exactly like the first but they call that teleportation. And effectively it is. The reason its so nifty is you don't have to measure or know these properties to transfer them. Thats the quantum part of quantum teleportation. Beyond that, I have no clue how they're applying a property of light to an atom.
I think Douglas Adams said it best:
I teleported home one night
With Ron and Sid and Meg;
Ron stole Meggie's heart away
And I got Sidney's leg.
Insisting on "correct" English is like saying that there is only one, definitive recipe for chili.
That yahoo article isn't really saying much at all. There is almost no real information on how they did it. Scientific American has a much more detailed description. http://www.sciam.com/article.cfm?chanID=sa003&arti cleID=000E9691-0261-1524-826183414B7F0000
In taking the next step, Eugene Polzik and his colleagues at the Niels Bohr Institute in Copenhagen shined a strong laser beam onto a cloud of room-temperature cesium atoms whose spins were all pointing in the same direction and fluctuating according to their given quantum state. The laser became entangled with the collective spin of the cloud, meaning that the quantum states of laser and gas shared the same amplitude but had opposite phases. The goal was to transfer, or teleport, the quantum state of a second light beam onto the cloud.
To do so, the group mixed a second, weaker laser pulse with the strong laser and split the superimposed beams into two arms. A detector in one arm measured the sum of the beams' amplitudes and a detector in the second arm measured the difference between their phases. Neither measurement disturbed the delicate entangled state between the light and cesium. But the researchers could use the results to apply a precise magnetic field to the cesium vapor that effectively canceled out the ensemble's original spin state and replaced it with one that corresponded to the polarization of the weak pulse, as they report in the 5 October Nature.
Stay sentient. Don't drink bad milk.
http://en.wikipedia.org/wiki/Quantum_teleportation
e orem). So you can teleport, but you can't teleport at greater than the speed of light because you still have to send the data to the destination.
Put simply you can record the quantum states of an atom/particle(or your entire body) and then send this information using a classical channel like radio. Once this information gets to your destination(eg Mars) the guys at that end can use that information to affect some particles over there, and because of Quantum Entanglement, those particles on Mars will instantly take on the recorded state. The particles at the start will then lose their state due to the no cloning therom(http://en.wikipedia.org/wiki/No_cloning_th
Note that it's not technically "Teleportation", you are just changing the states at the quantum level.
I don't need to test my programs.. I have an error correcting modem.
It's really quite simple. The system involves two opaque boxes (A and B), both with closable lids,.
One operator places the item to be teleported in box A and closes the lid. The operator of box B then opens the box and observes the contents. By doing so, the item appears in box B.
This works because of the way particle physics works. Any object may be in multiple places until it is actually observed. By hiding the item from one operator, the location of the item becomes unknown, and therefore the other operator is able to transport it to them merely by observing one of the locations it may have travelled to.
Really, this is elementary physics and it's surprising how rarely we take advantage of it. I actually go to work every morning by going to the bathroom, alone, closing the door, and then phoning a collegue at work, asking him to open the cubicle door at the bathroom there. By keeping my eyes closed at the precise moment he opens the door, I am able to ensure my own location is unobserved, and therefore that my precise whereabouts are unknown until my collegue opens the door and observes me. It's very useful and saves a lot of gas, but has the disadvantage that you have to rely upon there being someone whereever you want to travel to that you can contact who can observe the contents of a previously unobservable man-sized space. Also there's the danger that two people might do the same thing at once, in which case there's the danger of a time/space paradox being created.
You are not alone. This is not normal. None of this is normal.
Translating...
Its not a:
$ mv source target
Its a:
$ cp source target
Oh Gosh, now I fully know quantum computing!
ilex paraguariensis for all
Actually it is a
h eorem) which "forbids the creation of identical copies of an arbitrary unknown quantum state"
$ mv source target
Because of the No cloning theorem(http://en.wikipedia.org/wiki/No_cloning_t
I don't need to test my programs.. I have an error correcting modem.
Oh yeah, yer like being all smug and shit about it now, but just you wait until the day comes when he opens the door and observes you dead.
KFG
$ cp source target ; rm -rf source :-) )
(actually, I think mv does exactly this, but just to be explicit
And nobody has corrected this yet? Is this really Slashdot?
The "cp" operation will temporarily consume twice as much space as the original before the original is removed. Actual data is being replicated. "mv" (at least within the same file system) will leave the data where it is and merely change where the pointer (i.e. directory entry) that points to it is stored. With your version you have two files temporarily and a possible duplication if the operation fails due to a power outage somewhere in the middle. The normal "mv" operation could leave you with NO files (the data is still there but unaccessible) depending on how it's implemented. (No, not on journalling file systems, but thats something else again).
In particular, a "cp ; rm" will delete your original if the cp fails due to, say, a full destination disk. So at least a "cp && rm" is advised. Which can fail, for example, if some of your source data is unreadable. While "mv" will still work, since the source data is never actually touched. Depending on your filesystem, default flags and implementation, "mv" will often also not change the last-access or creation-timestamps, file ownership and/or file permissions which may or may not be changed by cp. Also the permissions needed in the source and destination directories can be different for the two.
Really - what's up with you folks out there? Why aren't there 20 posts pointing this out already?
We're all born with nothing.
If you die in debt, you're ahead.