Macroscopic Quantum Entanglement

meckardt writes: "We laugh at the science fiction of such programs as Star Trek, but it can almost be stated as a truism that what is fiction today may be science tomorrow and engineering next week. Researchers at the University of Aarhus in Denmark report in the science journal Nature that they have been able to cause particles to interact over a distance using lasers. The effect, called quantum entanglement, has been observed before, but never with such large amounts of matter. Don't expect transporters next week, but it is interesting that this report hits the streets the same day that Enterprise debuts."

Comments

Wow

[man_ls]

I wonder how long it will take before we won't even need to go to McDonalds to pick up our food from the drive-through. We'll just teleport our cash there and get our food back, right into our microwaves, or some other instrument.

Yummy.

Good

[NitsujTPU]

Now... if we can throw an atom smasher on mars we can get decent bandwidth to our next rover .

Better yet!

[SpanishInquisition]

Why not just teleport the whole thing directly into your stomach, that way you wouldn't have to taste the rotten meat and all the crap they put in there. And I'm pretty sure will be a cashless society when teleportation arrives.

Re:Better yet!

[SpanishInquisition]

Ouch, cosmetic surgery by teleportation.
Hey teenagers could even get breast implants over the phone if they can steal their parents credit card.

Re:Not true teleportation

[sacrilicious]

But it's NOT teleporation. Teleportation involves taking an object from point A and moving it to point Z without crossing the in-between space, C through Y.

Those of you out there who are lazy and want a free lunch, don't forget that you have to cross through point B! And from what I hear, qualifications to cross through point B are especially rigorous; physicists trying to unravel teleportation have dubbed its essential conundrum as "the Point B obstacle".

From the book about Milliways...

[Chris Brewer]

I teleported home one night,
With Ron and Sid and Meg,
Ron stole Meg's heart away,
And I got Sidney's leg.

Scientists observer quantum entanglement and

[scotch]

Scott Bakula returns to television tonight. Coincidence? Don't believe it.

Tron?

[sharkey]

Sounds like the matter transferance laser in Tron. Don't sit in front of it and piss off the computer.

MCP: Back again. Flynn?
Flynn: Well, well, well, if it isn't the Master Control Program.
MCP: You know I can't allow this, Flynn.
...

Re:Not true, B

[charon_on_acheron]

I just figured he opened up his "My Computer" icon, saw Drives A:, C:, D:, E:, F:, etc:, and decided that the letter B stopped existing when the single-floppy PC was introduced.

Re:Not true teleportation

[ENOENT]

Nature is a peer reviewed journal, and one of the more prestigious ones to boot.

Damn, here I've been going under the misapprehension that nature is a big open place full of green things and other things that can poop on you.

Re:Ansible

[uchian]

Great, does that mean I'd get decent pings when playing Counterstrike on an American server (I'm in the UK)?

Re:Not true teleportation

[stantron77]

My only question is where did B go?

Re:A Clarification...

[caffeinated_bunsen]

The faster-than-light seeming aspect of it appears disturbing at first. But after a while, you realize that it occurs anywhere in quantum mechanics when a wave function collapses.

Think about it. Consider 2 polarized photons, 2 electron spins, 2 billiard balls, anything entangled such that a particular measurement performed on each always returns opposite results. When the system is set up, each object's probability of being, say, spin up, is 50%. The two spins are described by coupled wave functions, so that the 50% that corresponds to A being spin up also corresponds to B being spin down and vice versa. When one is measured, its wave function collapses into a single eigenstate, and its partner's wave function collapses into the other eigenstate. Thus, the final eigenstate of B is decided by the same measurement that measures the state of A.

This seems disturbing, the instantaneous change of B's wave function an arbitrary distance from A, when only A is being measured. But the simultaneous collapse of 2 coupled wave functions is mathematically no different from the collapse of a single wave function. When you have a particle with a large uncertainty in position, mesuring its position causes it to collapse to a single position eigenstate. If you have 2 detectors some distance apart, and use each to measure the presence or absence of the particle some very short time apart, you know that if you observe it at one, you won't observe it at the other. Say the detectors are 10m apart, and they take their measurements 1ns apart. If you detect the particle at the first one, you KNOW that the second won't detect it. But the 'information' about the wave function's collapse at the first detector would take 33ns to reach the second, if it travelled at the speed of light. So a single wavefunction's instantaneous collapse from all of space to a single point is just as much 'communication' as an entangled particle pair's simultaneous collapse.

So you have a choice: Either the entangled particles' behavior isn't that disturbing, any measurement of a quantum system is really disturbing.

And the winning of Best Overstatement is ...

[Greedo]

regarding teleportation. it's simple.

I'm sorry, but that's got to make you laugh.