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IBM Tech Detects & Changes Spin of Single Electron
An anonymous reader writes "Looks like we have another step forward in Quantum Computing - IBM has discovered how to detect and change the spin of a single electron. Won't be long before we're all solving impossible encryption problems.
"
IBM Detects and Changes Spin of Single Election.
Damn you Taco, and your politics section, it's corrupted my mind!
... are they certain?
If spin can be measured in a meaningful way, the entire future of politics is suddenly up for grabs. Imagine a "spin detector" built into the home television!
Wow. "You spin me right round, baby right round, like a record baby, right round, round round...."
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
the new spin doctors? j/k
How can we know it's so?
Electron 1: Oh my god! they've found us! what can we do? we are doomed!
Electron 2: Oh stop being so negative
I am the lord of the pun. Dance Knave!
But they will have to dramatically increase the seek time of cats before this tech will be usable as a hard drive replacement.
You changed the outcome by measuring it!
It's good to see some tech companies actually innovate...
My website
So this allows read-write of qubits, right?
My Photography - http://ian-x.com
The Deathlings (comic) - http://thedeathlings.com
Whew, okay. After I RTFA I realized they hadn't done the impossible, just the really hard. IBM can measured the energy required to change the spin of a single atom not a single electron. (A prerequisite of this, of course, is detecting the spin of a single atom; but that's not that difficult with electron microscopes.)
So what do we do if quantum computers can decrypt anything in almost real-time?
All I can think of is making the data streams uninterceptable, which leads us back to encoders/decoders built using quantum entanglement.
**TODO** Steal someone elses sig.
I own a pump action golf ball cannon. I made it myself.
The Dept. of Homeland Security will be visiting you shortly.
I've just signed legislation that'll outlaw Russia forever. We'll begin bombing in five minutes.
IBM has discovered how to detect and change the spin of a single electron.
Measuring the spin of electrons bound to atoms was first achieved in the famous 1922 Stern-Gerlach experiment, a key stage in the discovery and understanding of quantum spin.
However, to quote from this discussion of the experiment, the Stern-Gerlach technique cannot be used to measure free electron spin because 'The spreading of the electron wave packet washes out the separation effect due to the electron spin'. Therefore, it appears that IBM's discovery is significant.
Tubal-Cain smokes the white owl.
Won't be long before we're all solving impossible encryption problems.
Of course by then we'll all be using quantum encryption techniques.
Overspinning electrons to overclock systems?
I'm quite sure the cat knows as well.
Mine mine! All mine! Your ideas are all mine!!!
A while back there was a proposal to have a public onetime pad system that worked like this. there is a server, perhaps a sattelite, that is streaming random numbers at say gigabytes per second. To encode a message you weakly encrypt a prior message to the recipient telling him a precise start time: say the message reads: start colleting your onetime pad at the first occurence of the first 5 digits of the number pi that come after 12 noon. you both then collect the data that comes at that time and treat ti as a shared one time pad.
you opponents may be able to decrypt the pre-message eventually but not it time to make the start time. thus they cant collect the onetime pad data. the data rate of the random stream is chosen so that no plausible storage system could retain more than say a few hours worth of the data, so no one could just record it all. As long as no one can crack your message on that time scale you can dsafely send the one time pad whihc no one can crack by technical means.
Some drink at the fountain of knowledge. Others just gargle.
This is the sort of situation where the Internet is more a hinderence than a help. Over time discussions such as this will polarize the lay community either for or against a particular area of research, wher two areas of research strive to achieve similar goals.
Public Opinion greatly influences funding of research, so I hope that premature dabates of which technology is superior, won't shape decisions to fund one or the other, since ther is the possibility that one or the other area of research might hit a brick wall at some time in the future, at which point it wll be nessecery to pursue the other area of study. It would be bennefitial to all to have continued both areas of research in parrelel. Don't get me wrong. I don't believe that discussions like this alone will influence the course of research, but merely that the colaborative enviroment the Internet offers will promote (suprisingly) colaboration to the point where only one research path will be pursued by both teams, working together, rather than competing, as it were.This is an area whewre competition is a positive thing in academic research. I merely question the degree to which the Internet actually contributes to this.
Were he still alive, Andre the Giant would have something to say about this sentence.
Obliteracy: Words with explosions
What IBM doesn't relize is that the electrons they are tampering with once passed through a SCO Unix system...
They can change the spin on OReilly factor..
That's not quite right either. If you have two electrons and nothing else the lowest energy state will be one up and one down.
In a molecular system, this is not necessarily the case. (Otherwise things wouldn't be magnetic)
Original poster: Won't be long before we're all solving impossible encryption problems.
Andre the Giant: As long as someone knows where they left all the mob gems!
Stop that rhyming, I MEAN IT!
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
They don't know exactly where they did this.
the major advances in civilization are processes which all but wreck the societies in which they occur - A.N. White
Personally.. I kind of doubt that they may ever become 'mainstream'. A quantum computer isn't an all-around "improved computer", it's a completely different paradigm.
So the question here is: Why would they replace traditional computers? There is no real reason to think that they will replace conventional computers, except for in the areas in which they are better.
(and that's not likely to be every area)
Quantum computers are inherently much more complex than traditional ones. Thus, they will likely always be more expensive to build.
It's 2004, and we're still using internal-combustion automobiles. Cathode-ray tubes for data visualization. Nearly all elevators still use ordinary cables and breaks. We don't have nuclear reactors in our basements. And so on..
The moral here is: Just because a technology is better in some respect, does not mean it's going to replace an older one. Especially if it's not better in every respect, and not cheaper.
From the article:
Over the past 15 years, Eigler has led a group of young scientists who have pioneered the use of atom manipulation in wide-ranging experiments aimed at building and understanding of the properties of atomic-scale structures and exploring their potential for use in information technologies such as digital logic and data storage.
Let's see... if they were 25 when Eigler started, they're now 40! Not so young anymore!
(it's a joke. laugh.)
Won't be long before we're all solving impossible encryption problems.
Who's this "we"? I still can't get my VCR to stop blinking 12:00...
"Was it a millionaire who said 'Imagine No Posessions?'" -- Elvis Costello
Green acres is the place to be
Farm living is the life for me
Land spreading out so far and wide
Forget Manhatten, just give me that country side
No need to thank me.
That is the degenerate or lowest energy state. If the only thing in the universe is two electrons, that is.
Materials are grouped according to how they respond to external magnetic fields as follows:
paramagnetic materials tend (usually strongly) to line up such that their spins are opposing the existing magnetic field, and therefore attracted to it. In classical terms, magnetic field lines permeate this material and cause attraction.
diamagnetic materials tend (usually extremely weakly) to line up such that their spins are aligned to the existing magnetic field, and therefore opposed to it. This effect is so small it usually can't be measured without very strong magnets or a carefully balanced system. Water is one of the most diamagnetic materials; if you're careful you can see the effect in one of those glitter lamps; let it settle down and still and hold a very strong magnet to the side, you can see the flow as the glitter moves away.
ferromagnetic materials tend, like paramagnetic materials, to line up such that their spins are opposed to external magnetic fields. However, they also tend to retain that orientation when the magnetic field is removed.
EVERY single material is one of the above. There's a proof (I forget who wrote it) saying that no static combination of electric, magnetic, and gravitational fields can be stable; that is, there is no combination of the above forces where something can be seen to levitate and balance the forces perfectly. The proof is almost correct; he didn't know there was such a thing as materials with a negative magnetic permeability (even though the permeability is slight it's enough in extreme circumstances)
Couple cool tricks:
1. If you've got a hugely strong electromagnet, you can float low size organic material in it. I once saw a video of a frog in a bubble of water levitating in apparent microgravity.
2. Certain kinds of graphite are strongly diamagnetic. The dust isn't, but the graphite layers are. You can shave flat little disks off and watch them float over an array of magnets.
3. Using bismuth and a couple neodymium magnets with a clever little gadget to help in positioning, you can make a frictionless bearing. Google if curious.
For those curious in playing around with strong magnets... forcefield.com is your friend...
I am disrespectful to dirt! Can you see that I am serious?!
There are two sides to every Schwartz.
"He's got the upside, I got the downside."
This is a big step forward in spintronics, not in quantum computing. Quantum computing is predicated on the idea that solutions to the Schrödinger equation can be a linear combination of several single-state equations; this is the case with any higher order differential equation. By detecting or explicitly setting the spin, you force the solution to be only one of these equations, and the quantum magic goes away. Great news for spintronics (using spin, not charge transporation to carry information), not news at all for quantum computing.
`which fortune`
Mix the principle from this Random Lava Lamp Generator, a high speed multi-mega pixel digital and film with a suffiviently high resolution, pipe resulting image as raw key-data, and you're done...
or if you prefer "better randomness" (sic) use HotBits cesium decay generated random numbers and pipe...maybe not gigabytes of data ( (about 30 bytes per second, to be precise, sucks...but then...
Mix both obtained key with the obscure, non repetitive algorithm of your choice (a simple XOR will be enough) and you can start having pretty impressive figures...
Generating gigabytes of data is quite easy, an I agree with you that making sure they are truly random is much more difficult, but it's not really that impossible 8)
The real problem is making sure both people get the SAME timepad, the problem here being to have both people REALLY in synch when startng the capture to generate the pad...
which is another problem entirely...
It takes 40+ muscles to frown, but only four to extend your arm and bitchslap the motherfucker
Okay, one answer is that CmdrTaco got it wrong. He said, "IBM Tech Detects & Changes Spin of Single Electron". He should have said, "IBM Tech Detects & Changes Spin of Single Atom". Huge difference.
--
Bush's education improvements were partly fraud
Won't be long before we're all solving impossible encryption problems.
Nothing impossible to solve is solvable, and nothing unsolvable is possible to solve.
I think the word you are looking for is intractable.
just = (My)Opinion.toCents();
Yes, but it's more general.
In QM, you measure a property of an object by applying an "operator" (you put in a function, and it spits out another function) to its wavefunction. Heisenberg said[*] that certain pairs of operators don't commute (meaning order is important - AB != BA), and so some pairs of properties can't be measured together.
"Position and momentum" is a particular example of a pair, as is "different components of angular momentum" (L_x and L_z, say). I can't remember how 'spin' fits into things, though ...
[*]Pedantry: Yes, I know Heisenberg talked about matrices, Schrodinger about operators.
Heisenberg is driving his car, when he gets pulled over by a cop. The cop asks him "Do you know how fast you were going?"
To which Heisenberg replies "No, but I know where I am!"
Step 1. Get a 1-bit quantum computer working
Step 2. Wire 1,024 of them together
Step 3. Break 1,024-bit encryption!
In reality, you now have the capability to solve 1,024 separate 1-bit problems. To solve a 1,024-bit problem, the electrons carrying each qubit need to be entangled with each other.
Keeping things in a state of quantum entanglement is extremely difficult. The most I've ever read about was 7 qubits entangled for less than a microsecond. Note that as the number of entangled objects (particles or molecules) increases, the operation gets exponentially harder. As the time to complete an operation increases, it also gets exponentially harder. Quantum computing boosters won't tell you this, but it is not just a matter of getting a prototype working and then making it bigger.
Random points:
Sure it will. Right after I receive my new, wall-sized television in a poster tube, unroll it, and hang it on my wall -- as I've been promised will happen any time now for the last 20 years.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Both the submitter and the guy who let this through should RTFA.
It's about a single ATOM
A-T-O-M
not
E-L-E-C-T-R-O-N
This could lead to incredibly high storage density [cat seek time joke deleted]"
But seriously: Did you notice some of the other related experiments from the same group, listed at the bottom?
One struck me: The inclusion of a single ferromagnetic impurity atom in a semiconductor, with its magnetization state producing a srong and extremely localized effect on the electronic properties of the semiconductor.
This might lead to a RAM where the storage element is a transistor with a single magnetic atom embedded in the "gate" region, turning it on or off depending on the spin of the single magnetizing electron.
Extremely tiny. Extremely fast to read (probably a ballistic-transport FET). Extremely fast to write (electron spin flips REALLY fast). Extremely low power (1/2000 electron volt needed to flip the spin).
And that's not even the most impressive thing in the list.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
...and the neighbor's cat dropped dead. CURSE YOU IBM!!!
It's supposed to be completely automatic, but actually you have to press this button.
http://news.nanoapex.com/
;-)
Why won't just ask Slashdot to post this link as permanent (along with wired.com )? I read it every day. They have diff. sections: nanotubes, nanoelectronic, nanoenergy, MEMS (nanomachines),... the first time I looked at it i became a nanoaddict
Just look at these nanoapex news regarding spintronics (reverse sorted by date):
Sep 03: Spintronics Breakthrough: Negative Resistance of a Single Magnetic Domain Wall Measured
Jun 23: Physicists Build New Microscope to Study Electron Spin
Apr 26: IBM, Stanford Collaborate on World-Class Spintronics Research
Mar 22: Silicon-based magnets boost spintronics
Feb 28: Spin valves open organic chip era
And that was just ONE topic. 'nuff said.
No, it will not work. Assume, my pre-message is use NBC + ESPN as the feed. The pre-message is decrypted after 1 week. I assume the evesdropper can get the archives form the respective stations and decode the message.
Same principle applies to using a paticular satellite. We can get information from that broadcast station and replicate the feed. Agreed, all this is not possible for the common man. But then RSA with higher bits is sufficient for the common man.
That was the reason I suggested we use some natural source like cosmic background radiation or some other random event in space which everyone can observe. No one has the abilty to record all the events simultaneously for long time (at least currently and in the near future). But it also makes the system very less practical.
Python script to convert photos into "artsy" portraits: http://p2pbridge.sf.net/pyPortrait/
How exactly does quantum computing allow us to solve impossible encryption programs? I may not be a quantum physicist, but I do have some basic understanding. Of course I have a basic understanding of electronics as well but no idea how to make an AND gate out of transistors....
The bigger use I see for this new technology isn't encryption, it is end-to-end communication without the possiblity of interception. In this event, you simply don't need to encrypt the transmission because it is impossible to intercept it anywhere except the transmitting and receiving devices.
Also could have great implications for the space program as such information "travels" faster than the speed of light. Travels is in quotes because perhaps the information doesn't actually travel as we think of it.
LedgerSMB: Open source Accounting/ERP
Things change spin all the time. Bang on an iron slug enough times with an iron hammer, and you'll start to magnetize both objects, just from the impacts.
IBM is an applied science lab. They found no value in making Hydrogen reverse its spin, and nobody but a particle collider holds onto one free electron; they're always on the move. IBM found value in measuring the required energy to apply to a certain metal used in their products, to make that metal reverse its overall spin.
[
Spin is basically a quantized angular momentum intrinsic to many particles (electrons are spin 1/2, photons are spin 1).
From classical mechanics (and quantum mechanics as well), linear momentum is the generator of translations and angular momentum is the generator of rotations. So linear distance and linear momentum would be canonical variables for Hamiltonian dynamics, just as well as angle and angular momentum would be.
There are some differences, though, by noting that translations in different directions are Abelian, while rotations are non-Abelian (Abelian operations are independent of the order of the operators). You can easily see this by taking any object and rotating along the X axis and then the Y axis. You'll get a different resulting configuration than if you rotated along Y first, then X. However, if you translate in the X direction first and then the Y direction, you are in the same place as if you translated Y first, then X.
Anyway, the generalized uncertainty principle relates the minimum uncertainty one can have through a combination of two non-commuting operators. The commutator for operators A and B is defined as [A,B]=AB-BA. The generalized uncertainty relation states that if [A,B]=i C for Hermitian operators A,B, and C (the i=sqrt(-1) is necessary for making everything Hermitian work out properly), then the product deltaA×deltaB=1/2|deltaC |(where deltaA is the uncertainty of that operator on the wavefunction (ie, deltaA=sqrt(A^2-A^2). The expectation value X is the normalized integral of the operator acting on all values of the wavefunction, giving an effective average value expected if infinitely many observations were measured.
For example, one of the primary consequences of quantum mechanics in one dimension state that [x,p]=ihbar (I might be off by a sign here). Plug this into the generalized uncertainty relation, and you get the well-known result deltax×deltap=hbar/2. Note, this is only true if x and p are acting in the same direction. If they're in orthogonal directions, the operators commute, and the total uncertainty product can be as small as zero.
Angular momentum operators, on the other hand, have the commutation relation [Lx,Ly]=ihbarLz, where Lx is the angular momentum operator in the x direction, and so on. What this means is that you cannot simultaneously know the x, y, and z components of the spin vector. In other words, you don't know exactly where the vector is pointing in space. For a single particle, you would be able to simultaneously know it's x, y, and z positions, but not its angular momentum. And you can see deltaLx×deltaLy=hbar/2Lz.
So while you cannot know exactly the angular momentum of a particle, you can know a little more about it than hinted above. The operator L^2, which is a measure of the total angular momentum, commutes with the other angular momentum operators. Ie, [L^2,Lz]=0, and similar for Lx and Ly. So for a system with angular momentum, one CAN simultaneously know the total angular momentum as well as the z-component of the angular momentum. A vector in 3D space needs 3 independent components to know it exactly, but for angular momentum we can only know two exactly. So there is effectively a cone of uncertainty that any particle with angular momentum (or spin) points along.
For the curious (if anybody even read this far) - if you studied chemistry and remember the quantum numbers for the periodic table, you'll recall n, l, m, and I think s. The l refers to the measure of total angular momentum and the m refers to the z-component of that angular momentum.
make world, not war
First of all, we won't be be able to crack any encryption.
Private-key encryption will still be just as safe (most likely).
Public key encryption based on factoring will be the first casualty.
Given the fact that patches, fixes, and reimplementations are developed and administered all the time, there's no reason to think that fixing vulnerable systems won't be a fairly trivial re-implementation of some sort. Even if a bunch of systems are left unpatched, it's a long way from IBM labs to some script kiddie's Quantum iPod.
There will be market-hyped hysteria, and a massive cottage industry of re-implementations of security protocols. Think Y2K but worse.
gears? we don't need no stinking gears