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Quantum Entanglement of Macroscopic Diamonds

Soulskill posted more than 2 years ago | from the simultaneously-a-girl's-best-friend-and-not dept.

Science 160

New submitter ananyo writes "A pair of diamond crystals has been linked by quantum entanglement — one of the first times that objects visible to the naked eye have been placed in a connected quantum state. 'This means that a vibration in the crystals could not be meaningfully assigned to one or other of them: both crystals were simultaneously vibrating and not vibrating (abstract). Quantum entanglement — interdependence of quantum states between particles not in physical contact — has been well established between quantum particles such as atoms at ultra-cold temperatures. But like most quantum effects, it doesn't tend to survive either at room temperature or in objects large enough to see with the naked eye.'"

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weird. (5, Funny)

notgm (1069012) | more than 2 years ago | (#38242976)

this both gives me the chills, and doesn't.

There is only "Here", There is only "Now" (1)

Jeremiah Cornelius (137) | more than 2 years ago | (#38243096)

Both are the same thing, which is infinite.

Time and space are illusions*. Try to prove them and you will only produce paradoxes.

* lunch time, doubly so.

Re:There is only "Here", There is only "Now" (2)

sehlat (180760) | more than 2 years ago | (#38243574)

There is only Xul.

Re:There is only "Here", There is only "Now" (1)

Jeremiah Cornelius (137) | more than 2 years ago | (#38244026)

Call it what you like. I was using "Brahma" and "Reality". :-)

Re:weird. (0)

Anonymous Coward | more than 2 years ago | (#38243606)

It simultaneously gives both you and I the chills -- the chills cannot be meaningfully assigned to either you or me.

Re:weird. (1)

mcneely.mike (927221) | more than 2 years ago | (#38244174)

It simultaneously gives both you and I the chills... and it simultaneously doesn't! FTFY.

Re:weird. (1)

thomst (1640045) | more than 2 years ago | (#38243646)

this both gives me the chills, and doesn't.

Well, then, put on a sweater ...

... and don't.

Re:weird. (0)

Anonymous Coward | more than 2 years ago | (#38244722)

or not

Re:weird. (1)

Dishevel (1105119) | more than 2 years ago | (#38244014)

I have those chills and not chills at the same time as you.

Re:weird. (0)

Anonymous Coward | more than 2 years ago | (#38244576)

It's probably quantum bird flu; it's probably kill you and not kill you.

Not wierd. (0)

Anonymous Coward | more than 2 years ago | (#38245126)

but rather... spooky.

--
AL

Re:weird. (1)

Darinbob (1142669) | more than 2 years ago | (#38245550)

A great disturbance in the force, like a billion voices crying and not crying out.

www.quantum-vibrator.xxx (5, Funny)

Slugster (635830) | more than 2 years ago | (#38243050)

great..... we dump all this money in some eggheads' laps, and all they can think of is to make fancy adult toys

Re:www.quantum-vibrator.xxx (0)

Anonymous Coward | more than 2 years ago | (#38244724)

Trolling or not, this comment needs more....

Quantum entanglement on a macroscopic scale like this can some day be used to transfer energy wirelessly and without loss of effect. Using a present-day example, we could attach a transceiver to a power plant in Norway, then ship another to say Indonesia and POOF! instant restoration of power even if EVERY power plant in Indonesia is destroyed.

Another example would be in the future. We have finally managed to colonize Mars (nice dream anyway), and when we went there, we brought a QE-transceiver with us. This made it possible to immediately start building after landing, and when the colonists felt homesick they didn't have to schedule a radiocall or prepare a manuscript from which to read and wait for a reply that would take at least 30* minutes to arrive.

Another present-day example would be to have QE-transceivers aboard planes, trains, trucks, cars and boats, getting rid of the release of pollutants to the atmosphere.

High-voltage powerlines for transfer of energy from one part of the world to the other could be torn down and never again desecrate and endanger the nature.

*Based on nothing scientific and I know it. Would be glad to hear how long it really takes for a radio signal to reach Mars.

Re:www.quantum-vibrator.xxx (0)

Anonymous Coward | more than 2 years ago | (#38245062)

Nope.

Re:www.quantum-vibrator.xxx (1)

holmstar (1388267) | more than 2 years ago | (#38245124)

I don't think you understand what entanglement means.

Quantum First Post! (4, Funny)

Dutchmaan (442553) | more than 2 years ago | (#38243052)

This is a first post, and yet it isn't!

Re:Quantum First Post! (1)

Tyrannosaur (2485772) | more than 2 years ago | (#38243166)

until we observe it, and cause your beloved post's wavefunction to collapse, and alas, you fail again.

Re:Quantum First Post! (0)

Anonymous Coward | more than 2 years ago | (#38244268)

No fair! Your pointing out his failure affected the outcome.

vibrating and not vibrating? (1)

sl4shd0rk (755837) | more than 2 years ago | (#38243076)

so..... the two crystals each have atomic particles sharing the same nucleus or something?

Re:vibrating and not vibrating? (2)

DogDude (805747) | more than 2 years ago | (#38243598)

No, that's quantum physics. Seemingly unrelated particles can influence each other. It's been widely known and accepted as fact since Einstein's era. It's just unusual to see it happen with such particles.

Re:vibrating and not vibrating? (1)

Yetihehe (971185) | more than 2 years ago | (#38244348)

No, they can't really influence each others. If one of the entangled particles is under ANY influence, you have decoherence and they are not entangled anymore.

next step in this study (4, Funny)

niw3 (1029008) | more than 2 years ago | (#38243102)

should be an experiment with a cat & some poison

Re:next step in this study (1)

bhagwad (1426855) | more than 2 years ago | (#38244276)

In this case, a woman can have an orgasm and not have it at the same time...since her state is intimately linked to the vibration of the device :D

Re:next step in this study (1)

mcneely.mike (927221) | more than 2 years ago | (#38244300)

Stick a cat in a microwave oven and turn it on. Then turn your back to it. Is the cat simultaneously both alive and dead?
Well, maybe once the meowing stops....
rimshot
Wow... tough audience....

Re:next step in this study (-1)

Anonymous Coward | more than 2 years ago | (#38244586)

EXPECT US

0.05 mm by .25 mm (4, Informative)

Anonymous Coward | more than 2 years ago | (#38243126)

They say that each phonon involves the coherent vibration of about 1016 atoms, corresponding to a region of the crystal about 0.05 millimetres wide and 0.25 millimetres long â" large enough to see with the naked eye.

0.05 mm is roughly 1/4 the width of a human hair. Of course, I still can't see it, because it's just a patch of vibrations on a much larger diamond.

Re:0.05 mm by .25 mm (1)

Loveless62 (1368353) | more than 2 years ago | (#38244454)

The article also implies that the entanglement only lasts a few picoseconds. I'm not sure I would consider that visible by the naked eye (I realize that the summary only suggests that the objects involved are visible to the naked eyes, not the effect itself). I guess it's a start, though.

Re:0.05 mm by .25 mm (1)

holmstar (1388267) | more than 2 years ago | (#38245178)

Well, of course you can't observe the effect directly with your eyes. The light bouncing off of the diamond would break the entanglement.

Re:0.05 mm by .25 mm (1)

CSMoran (1577071) | more than 2 years ago | (#38244906)

1016 atoms, corresponding to a region of the crystal about 0.05 millimetres wide and 0.25 millimetres long

Dawg, you got your lengthscales all messed up, man.

Harmony at last.. (4, Funny)

RenHoek (101570) | more than 2 years ago | (#38243158)

Neat... Now I can get a pair of diamond vibrators and please both my wife and mistress at the same time!

Re:Harmony at last.. (3, Funny)

roc97007 (608802) | more than 2 years ago | (#38243196)

Or not, at the same time.

Re:Harmony at last.. (5, Informative)

Baloroth (2370816) | more than 2 years ago | (#38243200)

Actually, no, because they are quantum entangled only one of them can vibrate at a time. So you can still only please one at at a time, you just don't know which one it will be until they tell you.

Re:Harmony at last.. (1)

blueg3 (192743) | more than 2 years ago | (#38243400)

I was actually going to mention this, and was pleasantly surprised to discover someone else pointing out what the common superposed state of entangled objects is.

Re:Harmony at last.. (1)

Bucky24 (1943328) | more than 2 years ago | (#38243504)

So (jokes aside) does that mean that if you vibrate one the other is forced to stop vibrating? (I don't understand quantum physics very well)

Re:Harmony at last.. (4, Informative)

Baloroth (2370816) | more than 2 years ago | (#38243758)

No. The experiment took one photon, and sent it along two possible paths without recording which path it took, which causes a vibration in one (and only one) diamond. Since the path of the photon was random, and not recorded, you cannot say which diamond is vibrating. The way the researchers put it (better than the summary IMO) is "Neither the statement 'this diamond is vibrating' nor 'this diamond is not vibrating' is true.” You cannot selectively vibrate one. In fact knowing which one vibrates destroys the entanglement. It does, however, tell you the state of the other diamond (the opposite) without observing it directly, which creates a few paradoxes and is the source of the whole 'spooky action thing.'

Don't feel to bad if you don't understand it, even quantum physicists don't understand quantum physics very well. The mechanics behind what is really happening in entanglement is still unknown, there is only guesswork as to how it might happen.

Re:Harmony at last.. (2)

tom17 (659054) | more than 2 years ago | (#38244290)

A great explanation, which made sense. But now I just have more questions. Like, "I will put a ball in one of these boxes, but I will not tell you which one I put it in. Now from your perspective, Neither the statement 'this box has the ball in it' nor 'this box does not have the ball in it' is true. You have no way of selecting which box I put the ball in." How is this any different?

What I am saying is, I don't see how there is any 'entanglement' there. It's just either in one diamond or the other. It's only our perception that doesn't know which one it is in.

I'd really love to get my head around this one day lol.

Re:Harmony at last.. (2)

Baloroth (2370816) | more than 2 years ago | (#38244616)

Well, as others point out I oversimplified things a bit. Quantum physics states that, in a sense, both and neither are vibrating so long as they are entangled, and only one actually vibrates once observed. However I believe that many view that as merely a mathematical system for approximating what is really going on (don't take my word for this, as I am by no means sure about this point), but that goes well past my knowledge. In your example, there is an objective reality about which box the ball is in. It may or may not (and experiments indicate not) be true that there is an objective reality about which diamond is vibrating prior to the observation.

Re:Harmony at last.. (2, Insightful)

Anonymous Coward | more than 2 years ago | (#38245186)

Well, as others point out I oversimplified things a bit. Quantum physics states that, in a sense, both and neither are vibrating so long as they are entangled, and only one actually vibrates once observed. However I believe that many view that as merely a mathematical system for approximating what is really going on (don't take my word for this, as I am by no means sure about this point), but that goes well past my knowledge. In your example, there is an objective reality about which box the ball is in. It may or may not (and experiments indicate not) be true that there is an objective reality about which diamond is vibrating prior to the observation.

But how can you prove that both diamonds were in a simultaneous state until observed? It seems just as likely that the photon went one way or the other and your just now finding out which way it went when you observed it.

Just like the two boxes, one has a ball and one doesn't. Just cause you don't know which one has the ball, doesn't mean it simultaneously exists and doesn't exist.

Re:Harmony at last.. (2)

holmstar (1388267) | more than 2 years ago | (#38245262)

That's called a hidden variable theory, and experiments have been done that show that hidden variable theories are incorrect.

Re:Harmony at last.. (1)

sonamchauhan (587356) | more than 2 years ago | (#38245502)

OK, _what's_ called a hidden state variable theory? Please? :)

Re:Harmony at last.. (0)

Anonymous Coward | more than 2 years ago | (#38244620)

There isn't entanglement in that situation, because the choice wasn't random in the quantum sense. It's not that we don't know which one is vibrating, it's that when the path the photon takes is literally not chosen when it makes the split. Half of the photon's probability density wave goes one way, half goes the other. Both diamonds are half-vibrating and half-not. The reason it's not just our perspective is that both paths are actually, physically linked. I'm not sure what the diamond vibrations could affect, but if you look at the standard double-slit experiment you can see how the split paths of a single photon can still interfere with eachother before the state is measured.

If your ball/box system were truly engangled, you would be able to - say - put both boxes on two sides of a scale, and they would balance out, even though one should be empty and the other should contain a ball. When you opened the one box to see if it contained the ball or not, then both boxes would suddenly and randomly take on their "correct" weight. (Except not really, because weight isn't a quantum state, but it's better than a car analogy.)

Re:Harmony at last.. (1)

Normal Dan (1053064) | more than 2 years ago | (#38244714)

I had your problem for the longest of times too. No one seemed bothered that this given explanation was no different than a classical example. And it seems most people don't ever think about it to the level that you have. (So congratulations I guess).

I think what you want to look at is Bell's Theorem. http://en.wikipedia.org/wiki/Bell's_theorem [wikipedia.org]

Re:Harmony at last.. (1)

johanwanderer (1078391) | more than 2 years ago | (#38245498)

A great explanation, which made sense. But now I just have more questions. Like, "I will put a ball in one of these boxes, but I will not tell you which one I put it in. Now from your perspective, Neither the statement 'this box has the ball in it' nor 'this box does not have the ball in it' is true. You have no way of selecting which box I put the ball in." How is this any different?

What I am saying is, I don't see how there is any 'entanglement' there. It's just either in one diamond or the other. It's only our perception that doesn't know which one it is in.

I'd really love to get my head around this one day lol.

Actually, it works exactly as the entangled diamonds in this case. I don't know which box the ball is in, so you can bring one box to Mars, keeping one here on earth. Upon opening the box here (measure) and finds that it is empty, I can instantly conclude that the box on Mars has the ball.

All this assumes that the boxes remain "entangled". If someone changes the content of the travelling box en route to Mars, then all bets are off.

Re:Harmony at last.. (1)

bhagwad (1426855) | more than 2 years ago | (#38244368)

Just to clarify - not being able to measure it doesn't mean there's an "underlying reality" which we haven't been able to observe. It's not that one of them really is vibrating and we just don't know which. They're both entagled meaning both of them are vibrating and not vibrating...or not.

Re:Harmony at last.. (1)

jpapon (1877296) | more than 2 years ago | (#38244926)

What I really don't get is why observation would destroy the entanglement. That just doesn't seem possible. They either are entangled, or they aren't. Mere observation by a third unrelated party shouldn't matter. Someone needs to just kill that goddamn cat.

Re:Harmony at last.. (2)

holmstar (1388267) | more than 2 years ago | (#38245240)

Observation requires interaction with the entangled object. Interacting with it causes the wave function to collapse and the object "chooses" a definite state. There is no way to passively observe the entangled object.

Someone correct me if I'm wrong but... (4, Interesting)

Shadow of Eternity (795165) | more than 2 years ago | (#38243170)

As near as I can understand this they're entangled so that vibrations in one are indistinguishable from vibrations in another, they both do the same thing at the same time (or near it at least)... doesn't this imply the ability to entangle two whatevers and transit information via entanglement induced vibrations?

Re:Someone correct me if I'm wrong but... (4, Informative)

Baloroth (2370816) | more than 2 years ago | (#38243378)

No, since when you establish the vibrations you don't know in which one it occurs. So while you could establish vibrations in a distant diamond (or particle), at least theoretically, you never know when you do so which one is actually vibrating. When they set it up, they used 1 photon that could travel and strike either diamond, creating the vibrations. Without measuring the photon's path, they didn't know which one it hit and therefore which on would be vibrating. This caused the entanglement.

Two things: 1), the photon itself had to be able to strike both (so not FTL at all for this setup) and 2) no useful information was encoded in this experiment. One thing you could do, though, would be send one diamond one direction and the other another way. Either can know the other diamond's state by reading his own (the other is in the opposite), and no one else can, since anyone else reading it would collapse the state, and a second reading would have a different result (I believe this is more or less how quantum cryptography works). Quantum entanglement is useful for transferring information (in other cases), but the mechanics still don't allow FTL information transfer, they just allow you to encode more in less space by having two bits quantum entangled. I don't completely understand the physics of that.

Re:Someone correct me if I'm wrong but... (1)

inviolet (797804) | more than 2 years ago | (#38243752)

No, since when you establish the vibrations you don't know in which one it occurs. So while you could establish vibrations in a distant diamond (or particle), at least theoretically, you never know when you do so which one is actually vibrating. When they set it up, they used 1 photon that could travel and strike either diamond, creating the vibrations. Without measuring the photon's path, they didn't know which one it hit and therefore which on would be vibrating. This caused the entanglement.

Close. The entanglement is created by the fact that the photon COULD HAVE chosen either one. Because the photon was not observed in such a way that it had to collapse into particle-ish behavior, the photon never had to choose which one to hit. Therefore, each crystal was AND was not hit by the photon. They only 'decide' who took the photon when the rest of reality (e.g. an observer, or an interaction with another incident particle) needs to know exactly who took it.

Re:Someone correct me if I'm wrong but... (-1)

Anonymous Coward | more than 2 years ago | (#38244356)

So basically what you're saying is they set something up so that they wouldn't know what happened without measuring it, and then they had no way of knowing what happened until they measured it. I do that at a macroscopic scale and at room temperature on a daily basis. Quantum mechanics is a huge scam.

Re:Someone correct me if I'm wrong but... (1)

blueg3 (192743) | more than 2 years ago | (#38243440)

It doesn't. That would fall within "quantum teleportation". It turns out that you need to transmit information in order to perform meaningful quantum teleportation, so it can't be used to transmit information any faster than you already could. (Even though, without knowing the details of how quantum teleportation works, it certainly seems like one ought to be able to.)

Re:Someone correct me if I'm wrong but... (3, Insightful)

LateArthurDent (1403947) | more than 2 years ago | (#38243472)

As near as I can understand this they're entangled so that vibrations in one are indistinguishable from vibrations in another, they both do the same thing at the same time (or near it at least)... doesn't this imply the ability to entangle two whatevers and transit information via entanglement induced vibrations?

No, they are in opposite states. If you measure one of them, you'll determine that it is either vibrating or not. If it is vibrating, the other diamond is not, if it's not vibrating, the other diamond is vibrating. Before the measurement, they're entangled, so they are considered to be both vibrating and not vibrating simultaneously.

That said, I don't know much about quantum effects, so I can't read the paper and understand it, but the description in the article made it seem like what's actually happening is just that the experiment is set up such that only one diamond can be vibrating, but you don't know which one it's going to be. So at all times, one of the diamonds is vibrating, the other is not, and you only know which is which when you measure one of them. Which doesn't sound like anything special. It's like me getting two playing cards, an Ace and a King, and putting them in a table face down. Then I ask you, "which one is the card in the left?" and you answer, "it's both a King and Ace. Until I flip it over, and then I can tell you what the other one is." Which is ridiculous, the card is one card specifically, you just don't know which one it is. So I suspect the media writeup screwed up, although it still seems way better than most, since they didn't mention stuff like ftl communications which pops up in almost every entanglement story even though we all know entanglement can't enable ftl communication.

Re:Someone correct me if I'm wrong but... (1)

dreemernj (859414) | more than 2 years ago | (#38243668)

I think it is a bit different then that since, as they mention, both diamonds are both vibrating and not vibrating simultaneously. It isn't the case that one is vibrating and the other is not vibrating and you just don't know yet because you haven't measured. They are both in both states until you measure. The entanglement means that when you measure one and collapse the superposition of simultaneously vibrating and not vibrating to determine which state it is in, the other diamond will be in the opposite state. So you are collapsing the superposition of one of the diamonds without actually measuring it.

Re:Someone correct me if I'm wrong but... (0)

Anonymous Coward | more than 2 years ago | (#38244658)

This sounds like complete BS :)

So, if I flip a quarter -- there is a 50/50 chance it has heads up (versus tails up). What you seem to be saying is that the quarter is both heads up and heads down at the same time. And once I look at it (measure it), then the two sides come "untangled" and it is not until that point that the two sides determine which one should be up and the other down.

How exactly can you prove (or better yet disprove) your assertion that both particles are BOTH vibrating and not vibrating at the same time? I can say there is a unicorn in my closet, but it always vanishes when I open the door too (prove me wrong).

Re:Someone correct me if I'm wrong but... (1)

narcc (412956) | more than 2 years ago | (#38243722)

Quantum mechanics does sound ridiculous, but it's the best-tested theory we have. Again, it's not that you "don't know" or "can't know" which path, which crystal, which whatever -- it really is "both" (e.g. "both paths", "both crystals"). It's frighteningly unintuitive, but this has held up experimentally (see: Bell's Inequality).

For some reason, slashdotters seem to desperately want to return to a nice, neat, deterministic, Newtonian billiard-ball universe where everything appeals to our intuition. Unfortunately for them, this is getting less and less likely every year.

Re:Someone correct me if I'm wrong but... (1)

kylemonger (686302) | more than 2 years ago | (#38245044)

Heh, no, I don't want to return to a classical universe. I like computers too much for that. I just wish there was some way quantum theory could make intuitive sense. Besides enabling the construction of modern computer hardware, quantum theory has firmly poked its head into the bailiwick of even software types like me in the form of BQP and what other NP problems it might contain, so I can't really ignore it. But at the same time, whenever I read a description of superposition I feel like a rube being enticed to play three card Monty.

Re:Someone correct me if I'm wrong but... (1)

ThosLives (686517) | more than 2 years ago | (#38243818)

This is also the part of quantum superposition that I don't understand. Given the text in the article and other things I've read, it does seem like it's the case you described with the cards. Yet the claim of quantum mechanics is is that, no, really, the diamonds (in the experiment) are indeed in both states simultaneously until they are measured. What I don't understand is how the measurement collapses the state, versus the collapse happening before the measurement (more like the cards).

The conceptual problem I have is essentially one of causality - how do measurement cause the state to collapse in a probabilistic way (as opposed to some other way)? Especially when the measurement probe (in this case, a photon) only targets a specific geometric location.

My personal opinion is that any single quantum event is deterministic, but we can't predict single events, so we use many events; because we are measuring many events, we can only come up with a probabilistic description.

I liken this to flipping a fair coin: The coin undeniably lands with one side face up or face down, but I cannot reliably predict which side it will be. I can only measure it after the fact. But, I can reliably say that if I do the experiment enough times, I will get 50% heads and 50% tails.

For entangled particles, I see it like two coins taped to each other and flipped as one unit, then split apart without looking at either of them. Then, when you look at one of them, you know exactly what the other will be. But the nature of this is probabilistic rather than deterministic, because I don't know what the result of any particular test will be; only what the result of a collection of tests will be. The key difference is, they two coins are in a particular state both before and after I measure them; I just don't know which one it is.

Can any of the physics PhD's out there shed more light on this subject?

Re:Someone correct me if I'm wrong but... (2)

jfengel (409917) | more than 2 years ago | (#38244332)

Nobody completely understands what "measurement" means, but in this case, what it means is that you have to interact the diamond with an even larger-scale system (i.e. your measurement apparatus, and then your eyeballs reading that measurement apparatus, and so on).

The more mass you add to the experiment, the smaller the variation can be, until it is effectively nonexistent. It must be in one state or the other, and you know that the two states will necessarily be opposite.

But as long as the objects are isolated from the rest of the world, they can potentially maintain superposition. It is in neither one state nor the other.

What you're talking about is called a "hidden variables theory"; the idea that it really is in one state or the other, but we just don't know which. That's classical uncertainty, rather than quantum uncertainty.

Surprisingly, it is possible to detect the difference between quantum uncertainty and classical. It's been done, and the hidden variables were ruled out. The explanation is rather involved; let's just say that it has to do with the difference between summing up all of the possibilities for the state (including the classically impossible ones), and you get a small difference. The WP article on it actually pretty good:

http://en.wikipedia.org/wiki/Bell's_theorem [wikipedia.org]

Re:Someone correct me if I'm wrong but... (1)

flosofl (626809) | more than 2 years ago | (#38244372)

Not a PhD, but I think the point is they actually aren't in particular state before they are measured (observed). They're smeared across all possible states at the same time. So the coins are equally heads AND tails. It's not until observation happens that it collapses into a this coin is heads or this coin is tails. Look up the double slit photon experiment. I seem to remember reading it and ALMOST having an epiphany. You may fare better.

And no, I cannot explain it or even understand WHY that is. All I know is it makes my brain hurt.

Re:Someone correct me if I'm wrong but... (1)

bhagwad (1426855) | more than 2 years ago | (#38244472)

No - the puzzling nature of entaglement lies in the fact that until you measure it, no result has actually occurred - even for a single quantum experiment. So in this case, it's not as if one of the diamonds is secretly vibrating and we just don't know which one. As Bell's experiments have proved multiple times, there's no "hidden reality." The two diamonds really are vibrating and not vibrating at the same time.

Only when an observation is made, does the wave function "collapse" and only at that time does one of them actually vibrate or not vibrate. Till that observation however, they are neither...and they are both...for real!

Re:Someone correct me if I'm wrong but... (1)

LeadSongDog (1120683) | more than 2 years ago | (#38245272)

No, only when the wave function collapses have you made an observation. I can't understand why this is so frequently stated backwards. The collapse is the observation. To paraphrase, a tree only falls in the forest once someone sees it lying on the ground.

Re:Someone correct me if I'm wrong but... (1)

tom17 (659054) | more than 2 years ago | (#38244660)

OK, I get what people are saying now. Not that 'it's in one state or the other, only measurement will show which one state' but that 'it is in BOTH states' and only measurement will make it become in one state.

Fine, I would accept that, but I can't 'just accept' things. This will likely make life hard for me as I need to know why they think this. As without anything backing it up, it's just an 'idea'.

So I imagine to understand the proof that something is in two states at once, I will need to learn quantum mechanics? Or is there a layman explanation that clarifies why they are so sure that thing X is in both states Y & Z simultaneiously rather than only being in one unknown state?

Re:Someone correct me if I'm wrong but... (1)

bhagwad (1426855) | more than 2 years ago | (#38245396)

It's been proved alright. But yes - to understand it completely you need some pretty heavy theoretical knowledge/math skills. As with most things in science these days, it's not "blindly accepting" if you choose whom to believe based on their authenticity. So "blindly accepting" something when the overwhelming majority of qualified scientists back it is a very smart move. Without doing that, I would have to doubt everything from relativity to the formation of starts. I've never actually tested whether or not the speed of light is constant regardless of the frame of reference. But I "believe" it because enough qualified people say so after the Michelson Morley experiment.

So your best bet is to "just accept" it after seeing who says so and are they reliable, and are they independent and is there a consensus?

FTL Communications (1)

fryguy451 (592591) | more than 2 years ago | (#38243176)

Next up, control a Mars rover in real-time.

Re:FTL Communications (1)

nomel (244635) | more than 2 years ago | (#38243520)

Yeah, who needs the laws of physics anyways!?

You still need a, at most, speed of light communication channel to correlate the two.

Re:FTL Communications (1)

RPGillespie (2478442) | more than 2 years ago | (#38244120)

at most or at least? To me, if the 2 crystals will be vibrating at the same time regardless of distance, the only lag would be in interpreting the vibrations on either end.

Re:FTL Communications (0)

Anonymous Coward | more than 2 years ago | (#38244858)

Killashandra? Is that you?

His Dark Materials (1)

ThunderBird89 (1293256) | more than 2 years ago | (#38243188)

When can we have a perfectly secure, instantaneous communicator that even works across universes and can be carried by tiny humanoids?

Just in time for Christmas shopping (2)

Accidental Angel (2899) | more than 2 years ago | (#38243194)

Entangled diamond jewelry -- how else can you demonstrate the superposition of your commitment to your one true love? (For 10 picoseconds.)

Vibrating diamonds are a girl's best friend (1)

OneAhead (1495535) | more than 2 years ago | (#38245300)

I mean, what's not to like about them? So many uses!

Diamonds really are forever (1)

Anonymous Coward | more than 2 years ago | (#38243208)

Ansibles are mere steps away.

Re:Diamonds really are forever (1)

newcastlejon (1483695) | more than 2 years ago | (#38243324)

Mere steps? I don't think so.
I'd say ansibles are more of a quantum leap away.

Does this mean... (1)

Slutticus (1237534) | more than 2 years ago | (#38243244)

Does this mean my wife could have a diamond of twice the size, until she looks at it?

Is this again just a theory? (-1)

stanlyb (1839382) | more than 2 years ago | (#38243316)

Am i missing something or there is still no evidence? For those who actually read the article, they don't give any video, proving their point, just...what, text, cheap words, entangled in quantum web, which under close observation (reading the text) disperse like a dust.

Re:Is this again just a theory? (4, Informative)

Taibhsear (1286214) | more than 2 years ago | (#38243496)

Did you actually read the article? "Cheap words" make up all science and literature. They explained everything they did in the article. Or do you expect them to post all their experimental data on this brief web article?

"When we detect the Stokes photon we know we have created a phonon, but we can't know even in principle in which diamond it now resides," says Walmsley. "This is the entangled state, for which neither the statement 'this diamond is vibrating' nor 'this diamond is not vibrating' is true."

To verify that the state has been made, the researchers fire a second laser pulse into the two crystals to 'read out' the phonon, from which the laser photon draws extra energy.

Re:Is this again just a theory? (1)

Anonymous Coward | more than 2 years ago | (#38243612)

You're correct. As of the 2007, the Scientists Guild requires all scientific evidence to be accompanied by visible light videos for stringent pixel examination. And, looking at a 2009 amendment, two viewpoints are required if the entire scene is many times smaller than a wavelength of the color orange, as it most likely is here.

the science education is what your're missing (0)

Anonymous Coward | more than 2 years ago | (#38244322)

Sounds like you're missing the actual science education.

A new musical! (0)

Anonymous Coward | more than 2 years ago | (#38243354)

Diamonds are a scientist's beeeest frieeeeend!

/goes away dancing and singing gracefully

Large enough to see (1)

Hentes (2461350) | more than 2 years ago | (#38243494)

They say that each phonon involves the coherent vibration of about 1016 atoms, corresponding to a region of the crystal about 0.05 millimetres wide and 0.25 millimetres long — large enough to see with the naked eye.

Problem is, if someone actually saw them the experiment wouldn't work.

Re:Large enough to see (1)

zlives (2009072) | more than 2 years ago | (#38243720)

only if she is already entangled... otherwise they just are.

Re:Large enough to see (1)

zlives (2009072) | more than 2 years ago | (#38243768)

sorry wrong thread.

Diamonds: (1)

DC2088 (2343764) | more than 2 years ago | (#38243584)

Simultaneously are and are not a girl's best friend.

Re:Diamonds: (1)

zlives (2009072) | more than 2 years ago | (#38243740)

only if she is already entangled... otherwise they just are.

umm..ok (1)

zlives (2009072) | more than 2 years ago | (#38243676)

"The optical properties of diamond make it ideal for producing tiny optical circuits on chips." what does that have to do with quantum states.... or am i missing something.

Explain to me again (0)

Anonymous Coward | more than 2 years ago | (#38243680)

Will someone explain to me again why must we consider two "superimposed" states, that "both" occurred, until we measure one of the two?

Why can't we just say that we don't know which of the two states happened until we measure it? Why all the ambiguity??

Re:Explain to me again (1)

bhagwad (1426855) | more than 2 years ago | (#38244522)

Because the Bell experiments destroyed that notion thoroughly....decades ago. It's not that we don't know. Reality takes a back seat until an observation takes place.

Soulskill : Get Rid Of The Stories (-1)

Anonymous Coward | more than 2 years ago | (#38243706)

the stories, may be from elsewhere; however, they ARE ALL on news.ycombinator.com

Fuck Soulskill.

Yours Truly,
K. Trout

Great (1)

RPGillespie (2478442) | more than 2 years ago | (#38244018)

Now let's give one diamond to my ISP, and one to me, and maybe I can get some information at a decent speed.

Other macroscopic examples (0)

Anonymous Coward | more than 2 years ago | (#38244360)

As far as I understand, the key is that the photon (and phonon) leave everything as it was. If the photon (or the phonon) somehow changed the state of the diamond crystal, the entanglement couldn't take place.

So I can suggest an even more mundane example of "Schrödinger's cat:" light traveling through the air. A photon leaves the lightbulb as a superposition of all directions (a ball wave) and interacts with the air molecules. But you can't tell which precise air molecules it "touches." No momentum or energy (or other quantum numbers) is transferred to them so the air is left intact by the photon. However, the interaction can be observed generally by the fact that the photon hits the screen "late."

What I find interesting is that light that is reflected off a mirror retains its quantum properties (interference). That means that a photon that is reflected back does not change the momentum of the mirror (measurably) because otherwise you could detect the change after the fact and determine the path taken by the photon.

Day of the Tentacle (0)

Anonymous Coward | more than 2 years ago | (#38244872)

Same plot

Living Proof? (0)

Anonymous Coward | more than 2 years ago | (#38244994)

So Mitt Romney is living proof of quantum mechanics?

Car analogy (0)

Anonymous Coward | more than 2 years ago | (#38245110)

Let me try this one...

You have a T shaped tunnel. Car goes in at the bottom, the drivers gets instructions to pick left or right at random. On both sides of the tunnel exits, you put a large glass plate across the road. Now you send off the car. It's important that you don't look which exit the car takes, no peeking! After enough time has passed for the car to have exited the tunnel, one of the glass plates will be broken, the other not. The 2 glass plates are now in an entangled state, you do not know which one is broken and which not until you look, you just know one of them is broken.

According to TFA the difficulty with the experiment seems to be that most cars never exit the tunnel. They must be using mice for drivers.

Can we detect wavefunction collapse, or not? (1)

Normal_Deviate (807129) | more than 2 years ago | (#38245196)

Detecting wavefunction collapse is trivial, just look for interference between the possible states, ala the two-slit experiment. HOWEVER, if the collapse of an entangled wavefunction can be detected, than FTL information transmission is possible, because collapsing one half of an entangled pair will instantly collapse the other half, causing the interference pattern (or whatever) to disappear. So what am I missing?

The Task Ahead... (1)

0xG (712423) | more than 2 years ago | (#38245236)

...is for us to simulate quantum entanglement in a digital object.
We have done it with neural networks, we can do this.
It will be very difficult (possibly profitable too), but a truly epic breakthrough.
Think of it.

Statistics not particles (4, Interesting)

dak664 (1992350) | more than 2 years ago | (#38245356)

Let us not lose sight of the fact that a photon is a statistical convenience, not a particle, and a phonon is even less a particle. You can't send "one photon" and detect "one phonon". These are statistical coincidence measurements that detect correlated behavior between the two diamonds after an electromagnetic interaction that can not transfer less than Planck's constant of action. Either diamond would show a 50% excitation in the absence of the signal from the other. Spooky action at a distance is inferred from correlation of the states over a large number of events. Which is why quantum computing is not going to be as fast as everyone thinks it will be.

Lodestone Resonator (1)

bradgoodman (964302) | more than 2 years ago | (#38245424)

Can you say: "Lodestone Resonator"?? :-O

What does those stones cost? (1)

Sla$hPot (1189603) | more than 2 years ago | (#38245584)

They cost a million bucks and they don't.
Huh?..Can i bring them home? : Yes and no!
WTF?? : Perhaps!

Jokes aside, i think entangled wedding rings would sell pretty well.
What about entangled ethernet cards for finance banks and hardcore gamers.
Or entangled radiators. Throw some in the Sahara dessert and sell the entangled cast iron opposites for $2.000 each :-O

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