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A Quantum Memory Storage Prototype
eldavojohn writes "An Australian National University project has completed a proof-of-concept storage unit that relies on bringing light to a standstill inside a crystal and then releasing it later for a read-once storage device. There are a few complexities to work out, such as the -270 degrees Celsius requirement to stop the light. And there is an interesting side effect noted by the team lead: 'We could entangle the quantum state of two memories, that is, two crystals. According to quantum mechanics, reading out one memory will instantly alter what is stored in the other, no matter how large the distance between them. According to relativity, the way time passes for one memory is affected by how it moves. With a good quantum memory, an experiment to measure how these fundamental effects interact could be as simple as putting one crystal in the back of my car and going for a drive.' Hopefully this will lead to a better understanding and simple testing of quantum entanglement."
Real-life neuralizer... (ok, more like blinding people)
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
Slow glass is one step closer to existence...
let our circadian rhythms be at peace
every day http://en.wikipedia.org/wiki/Special:Random
From you explanation, this device is more like a transmission device, not a memory device? Even better, if you ask me. I am beginning to dream about some fancy, quantum cell phone, untraceable, and extremely secure.
On my computer I have two specific pictures in my library that I've been trying to work with for quite some time. One is a picture of a nice bowl of steaming hot grits. The other a picture of Natalie Portman. Now, is it to be understood that with this new memory crystal technology I could effectively entangle the two? Let me know when Best Buy has them!
I do not respond to cowards. Especially anonymous ones.
Spooky action at a distance still seems fundamentally wrong to me. At what speed does information propagate between the entangled particles?
I've abandoned my search for truth; now I'm just looking for some useful delusions.
This would in one sense "break the laws of physics" - but as Quantum Physics and Relativity haven't been unified - one can't necessarily dictate what the other can or cannot do. Is there believe that this is possible?
you are a failure of a troll.
You have neglected to insult those from the European mainland: Mic, Guido, WOP, and Frog.
Shame on you troll.
and
you spelled 'Sorry' wrong.
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Read-once media combined with a flatscreen that explodes into a shower of neutrons after a single viewing. And all media outlets have become taco bell and they only sell crappy read-once media and home radiation treatments.
...even if the light is stored (paused motion), if the trigger to release the light is not light itself, how much is gained in overall potential for speed. If electrons are used to open or close "doors" to the light, would this be the same end response time as generating the light when needed? Putting theory into practice is fun, but where are they trying to head? Light transistors and memory are great if they are completely light based...otherwise, you are still waiting for the slowest part of the process.
jsut athnoer menagiensls ltitle psrhae for you to dcoede. Why do we wtsae our tmie dnoig tihs?
"There are a few complexities to work out, such as the -270 degrees Celsius requirement to stop the light." ...
"an experiment to measure how these fundamental effects interact could be as simple as putting one crystal in the back of my car and going for a drive."
The back of your car can hold a temperature of -270C?
I thought Egon said that crossing the streams was bad.
If we go back to the days where 'mainframes' filled up rooms and required ridiculous amounts of power, etc., I guarantee you the level of respect for our craft would increase. Plus it would bring about yet another generation of technospeak that noone else knows is bullshit, to use in getting PHBs off our backs.
http://xkcd.com/660/
Can someone please explain this to me ?
If two particles are entangled , modifying one makes the other take a reverse state.
So why can't this be used for transmitting data FTL ?
This is the clearest (if a little oversimplified) layman's illustration I've seen of what was proven in this paper.
"Liberty may be endangered by the abuses of liberty as well as the abuses of power." -- James Madison
There are a few complexities to work out, such as the -270 degrees Celsius requirement to stop the light.
Isn't that around what CERN keeps the thermostat on its air conditioning set at?
When we find out all that there is to know about particle physics, real soon, we could use the massive cooling systems at CERN to turn the place into a big light stoppage storage facility.
Hell, we could probably come up with some really cool stopping and starting light experiments, as well. I'd pay a high entrance fee to see light stopped!
Top that Mythbusters! I dare you to try to stop light!
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
No, I'm saying that when you're ready, you won't have to.
Actually liquid helium as someone already observed, but never mind which element it is. You are thinking of an insufficiently advanced technology. Let's not confuse technological limitations with physical limitations.
A microscopic droplet of liquid helium is exactly as cold as a whole planet made of liquid helium. The way I imagine a handheld cryogenic device is as a tiny box whose walls are made of multiple layers of Peltier chips.
I've got a quantum memory in my computer right now, in the sense that flash memory exploits quantum tunneling to flip bits.
...there are at least two people who have made it most of the way through Zardoz!
If I have seen further it is by stealing the Intellectual Property of giants.
I mean if the crystals are entangled and you put one of them on a spaceship and accelerate it to near c for a long enough period, when you change its state, at what moment will the other crystal change?
I don't know the meaning of the word 'don't' - J
I am so sick of news reports claiming that if you alter one entangled particle, that the other entangled particle is affected too - like if you push one, the other one moves. IT DOESN'T!
What happens is if you measure the state of one particle, and then you measure the state of the other particle, they are always equal (or opposites, depending on the entanglement type).
Think of it this way... You have a CD burner that burns two CDs at the same time and puts random data on both, but the random data is identical. Obviously, no matter how far away the CDs are, if you read them, they contain the same information. There is absolutely zero information transfer going on here!
-Bill
I'm no physicist so pardon my ignorance but maybe you can help explain. Are we able to change the state of one of these particles at will? And if we are, does the other entangled particle change states as well?
If the two particles simply exhibit a mirror-like effect but we have no way of changing their state, then I agree that this is quite useless at this stage. However, if we are able to change the state of one particle and the other changes as well, then we can have data-transfer (think 1s and 0s, ON and OFF) across limitless distances.
Military would salivate over this a communication channel that cannot be interrupted through regular means like rock and walls, yet is absolutely un-tappable no matter where you are in the universe.
The magical number is: 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
The problem with building a memory stick out of quantum memory would be that you'd never be able to know both what's on the thumb drive and where you left it!
If intelligent life is too complex to evolve on its own, who designed God?
I couldn't get my head around it either.....until I read this..
http://quantumtantra.com/bell2.html
puts it into 'simpleish' terms, for non quantium physicists like me!
That's incorrect. Remote state preparation absolutely does change the state of a distant particle. For example, consider the case that you have correlated particles such that they will both be measured in the same same state. Each particle is in a superposition of state 1 and state 0 but if one is measured to be a 1 then it prepares the other in state 1 and vice versa. Both particles could be in either state until one is measured, at that point the state of the other is prepared in the state of it's partner. No information is transmitted; however, because the state of the first particle is random anyway.
Read up on Bell's Inequality or the EPR paradox for an explanation of the fact that the state is truly random until it is measured and hence the entangled particle is remotely prepared.
So if this is the future...where's my jet pack?
However, if we are able to change the state of one particle and the other changes as well, then we can have data-transfer (think 1s and 0s, ON and OFF) across limitless distances.
You have hidden assumptions here. We are able to change the state at will, but we are not able to choose what state we change it to, and it's a one-time operation. All you can "communicate" is entirely random data -- which is very useful for quantum cryptography when combined with a classical communications channel, but doesn't have many other evident uses.
Suppose you have two entangled particles, and you put one in a space ship which travels at relativistic speeds for a while. The ship comes back, and 100 years have passed for the other particle. Would the particles still be entangled? If so, what would happen to the other when one's state changes?
Correct, otherwise there would be no "spooky action at a distance", as Einstein put it.
A lot of people explain it like this: You write two notes, one has the letter A on it, the other has the letter B on it. Then you put them in envelopes and mail them to two different people. When one of them gets the envelope, they instantly know what the other person got.
This explanation is incorrect, because there is no letter A or B until either is observed with quantum entanglement.
A better explanation would be: You put two pieces of magic paper in envelopes, without looking at them, and mail them to two different people. When the first person opens their envelope and looks at the note, it will switch from random to display either the letter A or the letter B. The instant it does, it magically instantly tells the other piece of paper to show the other letter. It really does transfer its state faster than the speed of light, we just can't use it to transfer information faster than the speed of light.
And read up on the many-worlds interpretation to see how this can be explained without any need for instantaneous transfer. The instantaneous transfer of information is an artifact of the Copenhagen interpretation of quantum mechanics.
I'd like some "spooky action down under."
One thing I always wondered:
Let's say I have a total of 1024 entangled pairs; well contained and stable. Now, I take the one half of those pairs and transport them somewhere else. Then, I proceed to measure the state of them _or not_. When checking the other half, shouldn't I get a total of 1024 "altered" and "unaltered" read-outs, resulting in the transmission of 128 bytes?
Granted, it's still hard to do all this, but afaik, what I just described is FTL transmission of actually useful data.
As I am sure there is some pitfall with which the quantum theories foil FTL plans (they seem to do that pretty reliably), I am eager to learn what trick those pesky laws of physics will pull out of their, admittedly tiny, hat, this time.
"could be as simple as putting one crystal in the back of my car and going for a drive, hitting 90 MPH and one Gigawatt later... fwoosh!"
I see, it makes more sense now - thanks.
The magical number is: 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
One thing I always wondered:
Let's say I have a total of 1024 entangled pairs; well contained and stable. Now, I take the one half of those pairs and transport them somewhere else. Then, I proceed to measure the state of them _or not_. When checking the other half, shouldn't I get a total of 1024 "altered" and "unaltered" read-outs, resulting in the transmission of 128 bytes?
You can't measure if a particle is entangled, or if something was done to the entangled pair even if you know it's entangled.
So no transferring information that way, sorry.
If that is the case why do we even know about entanglement in the first place? And why do we care about that fact?
If that is the case why do we even know about entanglement in the first place?
Well, if we have both particles we've ourselves made entangled, and then measure both (in whatever order, , we see that they indeed were entangled.
And why do we care about that fact?
Well, it used to be pretty much basic physics research, but we're approaching the point where we have practical quantum cryptography and then practical quantum computing, and who know what future applications we come up with. Being able to stop entangled light sounds like a pretty nifty building block for future technologies. I don't think anybody looked at the first huge proof-of-concept transistor in a lab and said "hey, I know, people will use technology based on this to write on global discussion forums, while sitting on a beach at the back-end-of-nowhere".
>Well, if we have both particles we've ourselves made entangled, and then measure both (in whatever order, , we see that they indeed were entangled.
So I can prove that the _were_ entangled by a measurement which destroys said entaglement?
> I don't think anybody looked at the first huge proof-of concept transistor in a lab and said "hey, I know, people will use technology based on this to write on global discussion forums, while sitting on a beach at the back-end-of-nowhere".
Point well made & taken.
>Well, if we have both particles we've ourselves made entangled, and then measure both (in whatever order, , we see that they indeed were entangled.
So I can prove that the _were_ entangled by a measurement which destroys said entaglement?
Yeah. Which proves that the method to make them entangled works (or tells how reliably it works, statistically). And then that method can be used to create entangled particles for whatever other purposes than just testing if entanglement works.
It's worth noting that measuring just one pair, and finding them in states where they could have been entangled proves nothing, as there was 50% chance that they were in those states just by coincidence. But when 50% probabilities keep adding up, you can be more and more sure it's not coincidence, until it's practically certain.
So basically I create entangled pairs with probability X and hope they are entangled when I do stuff with them?
Question is: what are the [envisioned] uses?
No, they make more sense if the universe is a *DREAM*, than something quantized in finite "bits and bytes", or quantum ones, whatever that would be.
Remember we piece everything together from *WITHIN* the "dream", or "simulation" if you'd like to call it that, so our understanding is based on too large limitations to be able to tie every obervable "facts" together.
Only way we ever progress scientifically, culturally and spiritually, is whenever we embrace a larger reality and let go of our own limitations and small-minded concepts.
So basically I create entangled pairs with probability X and hope they are entangled when I do stuff with them?
Question is: what are the [envisioned] uses?
I don't know if there's anything else practical, except quantum encryption and quantum communication (100% secure, as an eavesdropper would destroy the signal) and quantum computing, and more dense information storage. I think there's some research into quantum compression or "superdense coding", but I don't know if it can produce just 50% compression, or if it's possible to for example use 64 qubits to store 64^2 bits of information, or whatever.
In a less cheery note, quantum technology could probably be used for creating one hell of a DRM system as well... Hopefully we're past those by the time it becomes practical...