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Laser Beam Teleported
Michael Wardle writes "ABC Australia reports that a team of scientists from the Australian National University have successfully teleported a laser beam. It seems that teleportation of solid bodies is still a way off, but at least we're a little closer to Slashdot's favorite super power." Another Australian newspaper has a more detailed story.
It seems to me, that there is a huge difference:
Team leader Dr Ping Koy Lam says it involved creating a laser beam, its disembodiment and the recreation of the original beam in a different location.
To me, that sentence can be translated as such:
Team leader Ping Koy Lam says it involved creating a ball point pen, its destruction and the recreation of the same ball point pen using a factory blueprint in a different location.
This isn't the first time I've read about "teleportation" of some particle or another, when it seems that they are simply re-creating, mirroring if you will, the particle(s) quantum states in another place. That's not teleporting - that's mimicing.
Man is born free; and everywhere he is in chains.
Team leader Dr Ping Koy Lam says it involved creating a laser beam, its disembodiment and the recreation of the original beam in a different location
The team was understood to be using a device known to insiders as a "video camera", although how it functions exactly was not disclosed during their press release
What if they could scan the original you, make sure they have two or three backups first, and confirm several long checksums of the backups versus the copied you, before they killed the original you? Would it be acceptable then?
For all practical purposes, it is like if you die (and disappear) each time you go to sleep, and your complete copy gets reconstructed at the instant you wake up.
Given that cells of your body don't live long, you are a new, reborn person, every N years.
The key to perceived continued existence is the slow transfer of your consciousness into another body, with clear departure from the old one. The copy operation (cp) is not good enough, you need the move (mv) here.
Can anyone give a layman's explanation of how the information is getting passed from point a to point b?
Magic.
I have been pwned because my
The "spooky action at a distance" is a weird consequense of the heisenberg uncertainity principle. It 'appears' to be an interaction, but in fact it's just the result of the coherency between two 'entangled' wavefunctions.
the 'yes' part is that to receive a teleportation, you have to have one of the entagled particles, and a measured quantity.
the 'no' part is that since the measured quantity is transmitted classicaly, there's no FTL transfer of anything.
-Kz-
The URL you have provided is for a page published by a student undertaking a first-year physics course. Whilst it may (or may not) contain some good content, I doubt the student is part of the research team, and the page should not be treated as authoritative.
The page at http://photonics.anu.edu.au/qoptics/ is somewhat more official.
As any teleportation device could clearly be used to replicate 'N Sync CDs, its use will be obviously be prohibited by the DMCA.
ok then your [sic] infringing on my copyright! Could you as [sic] me next time before STEALING my comments for your own?
The blueprint analogy shows a lack of understanding of entanglement. There is no blueprint at the receiving end, and no measurement and communication of instructions to replicate the properties of the sending photon. What happens is a seemingly spontaneous change in the properties of the receiving photon.
Whether this is teleportation or replication is more of a philosophical question, or maybe a matter of semantics. Is an object (or a laser beam) equal to the sum of its properties? If you can make the sum total of an object's quantum properties disappear from one place and reappear in another place, have you merely copied the object or have you moved it?
I think you've moved it, but questions like these deserve more than offhanded answers.
It's bad enough people are sharing music and movies over the net, the last thing we need is people to start sharing themselves online!
oh, wait...
FreeBSD for the impatient.
I'm still considering very fast traveling of the light. If there was an impediment between the 1 meter, I'd consider teleportation.
There's a relativly (pun intended) interesting experiment on NEC Institute's web page. It proves that light can go faster than C. Here for NEC Faster than C webpage
It seems that this beam of light traveled about 3C. However, there's conjecture that it traveled slower, but time dilation made it seem 3C. That's unprovable at the time though.
Here is an informal talk by Samuel Braunstein on the problem of teleporting humans.
17779 eligible voters in a district, 17779 'vote' as one. This is Russia.
"An encoded radio signal is embedded on an input laser, which is combined with entanglement and then scanned. The laser is destroyed in the process. But the radio signal survives and is sent electronically to a receiving station, where within a nanosecond an exact replica of the beam - with the radio signal intact - is retrieved and decoded."
First, a simplified definition from my very limited research into Quantum Entanglement: The supposed link between particles that have once interacted, enabling them to influence each other instantaneously over indefinite distances.
I'll mention before hand I'm not a quantum physics major of any sort, but if I'm reading this correctly, they have encoded a laser beam with a radio signal and "quantum entangled" the two mediums which is then "scanned" (whatever the hell that is) in which the laser is destroyed in the process. So now we should supposively have an intact radio signal with a "destroyed" laser sub-atomically anchored to it in ether somewhere. Sending this radio signal downrange to a receiver will recreate this signal and "pull" the laser back into reality (pardon my butchering of terms).
My problem here is perhapse not how unbelieveable this sound, but how damn vague the artical is. Scanning? How the hell was the beam recreated? Did it appear from thin air? Did it have to be "un" entangled? It doesn't seem as if the laser is infact destroyed at all... How do you go about "entangling" something to being with? This artical doesn't simply bog you down in scientific explanation; In fact it doesn't bog you down in ANY explanation for that matter-- it throws some words in and stirs them up with teleportation references. Hell, the only way I could figure out ANY details was independent research, and oh, how fun that was. The above definition was as easy as it got. After that? Whew... Maybe I'm just bitching, but I'm asssuming this article was written for the common man, but goes far beyond watering things down. It leaves out key pieces nessisary for understanding to occure. Jeez, that's shitty writing...
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I have a great idea for a device which will employ this new technology...
How about a device that will teleport the laser back into the eye of the dumbass teenager shooting his laser pointer on the movie theater screen?
-- We live in a world where lemonade is artificial and soap has real lemon.
The question is begged, "what is the point of making a a laser go the speed of light? Isn't that like making a german sheppard go the speed of dog?" and the answer is um, sort of. Because the laser is reconstructed at the other location sort of faster than the speed of light, in that half of it arrives instantly (FTL) and the other half arrives at the speed of light.
This doesn't make any sense, but that's cool, so we'll keep going. The important thing to note is that the two halves of the laser beam (not really half, in the terms of 1/2 intensity or anything like that, it's more about the polarization, but we'll gloss over that) are needed to transmit any information. That's any information at all, including if the laser is even turned on or not.
That means that half of the laser can arrive from Jupiter, and the other half is en route for however long it takes for light to get here from Jupiter and you pretty much have to wait around.
(Actually, you can do a whole bunch of nifty calculations while you're waiting, and this is usually a good idea, but I've already dreadfully confused myself so let's skip that part.)
Then your speed-of-light transmission arrives with the other half of the data and you can reconstruct the original. Which is fabulous, and actually quite exciting, but importantly not faster than the speed of light.
Information turns out to be limited just like everything else is by the universal speed limit of 3X10^8m/s. So, if you want to go past, say, Mars, you're going to have to be ready for some lag on your phone call home. It's sad, but it's true.
Everything above may well be poorly-thought out / spelled. Blame the beer, not me.
I teleported home one night,
With Ron and Sid and Meg.
Ron stole Meggie's heart away,
And I got Sidney's leg.
"Information wants to be paid"