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.

Comments

Amazing Science

[Wrexen]

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

Re:Question

[ObviousGuy]

Can anyone give a layman's explanation of how the information is getting passed from point a to point b?

Magic.

DMCA violation?

[aozilla]

As any teleportation device could clearly be used to replicate 'N Sync CDs, its use will be obviously be prohibited by the DMCA.

Replication or Recreation -- not an easy question

[serutan]

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.

Re:I'm not getting in one of those things

[discogravy]

As long as those are legitimate back ups, and just for back up purposes, sure.

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...

On teleporting humans

[Vadim Makarov]

Here is an informal talk by Samuel Braunstein on the problem of teleporting humans.

Re:Teleportation, or recreating?

[Lemmy Caution]

The answer to this dilemna is to realize that the person we were 10 minutes ago is dead. The person you were 10 years ago is very very dead. Each second that passes, what we were passes out of existence, and the the self that seems to be the unitary point of existence is just a collection of modalities and a small amount of working-memory. It sounds Buddhist, but it's more informed by neuroscience: there is no self as such.

Re:Faster than super fast!

[037]

Yeah, FTL communication is cool, and I would agree that it is vital if it were at all possible, and I mean at all. It's not. The truth is that this type of laser teleportation is pretty arcane stuff, and doesn't move faster than the speed of light.

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.