Quantum Computing Using Traditional Transistors 323
Ocean Consulting writes "UCLA is reporting progress on the quantum computing front by announcing success in controlling the spin of a single electron using an ordinary transistor." It's been a long road for the researchers involved, and even the project lead, Hong Wen Jiang admits, "...our initial theoretical calculations were very favorable, and gave us confidence to persevere."
Awesome! (Score:4, Interesting)
"With 100 transistors, each containing one of these electrons, you could have the implicit information storage that corresponds to all of the hard disks made in the world this year, multiplied by the number of years the universe has been around," Yablonovitch said. "And why stop with 100 transistors?"
That is pretty amazing.
Cheers!
Erick
Re:Awesome! (Score:2)
Re:Awesome! (Score:3, Interesting)
Actually making use of those squillions of quantum states is something else entirely. It's not like you can just store that much information in 100 transistors, it's that it contains all possible combinations of those 2^100 quantum states while it's running.
OT: wrt to your sig (Score:3, Funny)
Karma: pi (Mostly due to circular reasoning in posts).
Sir:
Your sig is irrational.
Just thought you'd like to know that.
Re:Awesome! (Score:2)
Re:Awesome! (Score:2)
Quantum computing in general is one of the most exciting technological developments ever. I love reading about progress in this field.
Re:Awesome! (Score:3, Insightful)
It's kind of like saying a room full of monkeys implicitly encode all the works of Shakespeare.
Re:Awesome! (Score:2)
Yes, and no... Classically, no, but if they were quantum monkeys...
The point of quantum computing is that each electron can simultaneously have two spin states - used as a 0 and 1 - and can therefore be both a 0 and 1 simultaneously. 3 qubits - (|)(|)(|), being both 0 and 1, encode 8 states, 000, 001, 010, 011, 100, 101, 110, and 111... all at the same time.
So, a roomful of quantum monkeys, each of whom presse
Re:Awesome! (Score:2)
Secure communications? (Score:5, Insightful)
So which is it, secure communications or communications that can be spied on? It can't be both.
Re:Secure communications? (Score:2)
Cheers!
Erick
Re:Secure communications? (Score:3, Informative)
Re:Secure communications? (Score:3, Informative)
This is how quantum computers can break encryption
I'm not sure what they mean by the encryption that is secure though; Quantum encrytion as such is completely separate from Quantum computers, it is just a clever method using detection of the polarisation of light.
The sending computer begins by sending photons in one of four con
Re:Secure communications? (Score:2)
What?
Let me see...
Oh, here it is, The Code Book by Simon Singh, page 244: "RidiculousPie is not a physicist."
Must have been kind of weird to find that out in such a way.
Re:Secure communications? (Score:4, Informative)
Using a quantum computer it can search every possible key simultaneously, cracking the encryption almost instantly. An example to understand this, you are in a building searching for your briefcase. Normal computers would go through every room one by one until they find it. A quantum computer would find the briefcase by existing in every room at the same time, finally settling (existance wise) in the room with the briefcase.
They also mention quantum cryptography being uncrackable, this is true. If someone eaves drops on communication that is encrypted, it inherently destroys the data. The users will recognize intrusion and the eavesdropper cannot decrypt the message because the data has been destroyed.
So yes, quantum computers can decrypt normal encryption that can be broken by exhaustive search and they can be used to provide quantum cryptograph which is a theoretically unbreakable form of communication.
Re:Secure communications? (Score:5, Interesting)
if eavesdropping on the encrypted transmission destroys it, couldnt the eavesdropper do so on purpose everytime, effectively jamming all transmission? Little point in having a secure way to communicate if no message can ever get through.
Re:Secure communications? (Score:3, Informative)
Re:Secure communications? (Score:2)
Re:Secure communications? (Score:4, Interesting)
But since real transmission lines (even the best optic fibers) will always lose photons, you have to start adding on complicated processing to deal with the losses. Were the photons lost due to natural causes, or is someone eavesdropping? And if data is duplicated to account for losses, the system can possibly be tricked by an attacker into revealing information. This is a delicate subject and a great cause of complication in the field!
The communications can also be jammed of course but the focus of the technology is delivering a secure link.
Re:Secure communications? (Score:2)
Re:Secure communications? (Score:2)
Google for sites that explain the whole process. It does in fact work.
Basically, you transmit a one-time-pad over the encrypted link. If it was unintercepted, then you use the pad to encrypt your data, send that over normal communication routes, and decrypt that at the other end. A one-time-pad is of course unbreakable.
If the pad was intercepted ov
Re:Secure communications? (Score:2)
Not strictly true in all senses: some implementations use quantum effects to share a string of truely random -- not pseudo-random [wikipedia.org] -- bits which are then used in a one-time pad [wikipedia.org]. If someone eavesdrops on the exchange, it can be detected, and the message aborted (or change
Re:Secure communications? (Score:2)
- Oisin
Re:Secure communications? (Score:3, Insightful)
My understanding was that this is not true. At best you get the square root of the number of steps that would be required for a non-quantum brute force search. This means that key sizes are effectively halved, but that isn't an insurmountable problem.
A bigger problem is that some algorithms are intrinsically vulnerable to quantum computing (or to rephrase, take far, far fewer steps to revers
Re:Secure communications? (Score:4, Informative)
Bingo. Which is why the AES competition required support for 256 bit keys, when even 128 bits is out of reach by any conceivable technology.
Factoring is one such case, which is why quantum computing spells the death of RSA.
Not true, necessarily. Shor's algorithm is algorithmically faster than the generalized number field sieve, but there is a constant in there. We don't know how big that constant is, and we won't until we have a quantum computer big enough to run Shor's algorithm (30 qubits or so, IIRC). It's entirely possible that Shor's algorithm is only faster then the GNFS once you hit keysizes of 10,000 bits, in which case it doesn't matter. OTOH, if Shor's algorithm is faster than the GNFS on 256 bit keys, we are, indeed, in some trouble. Of course running Shor's algorithm on a 1024 bit RSA key would take quite a large quantum computer, too.
And, as you mention, there is no algorithm for compute discrete logarithms much faster than usual on quantum computers. I haven't heard about such an algorithm, anyway. Doesn't mean it doesn't exist, of course.
Summary: algorithmic complexity is not the sole determinant of algorithm running time.
In summary, quantum computing is powerful, but not a magic wand that makes all classical encryption schemes invalid.
Thank you. Every time a quantum crypto or quantum computing store pops up here, the hype level seems to increase by several orders of magnitude. It's really annoying.
Now that's a huge hard drive... (Score:4, Insightful)
"With 100 transistors, each containing one of these electrons, you could have the implicit information storage that corresponds to all of the hard disks made in the world this year, multiplied by the number of years the universe has been around," Yablonovitch said. "And why stop with 100 transistors?"
Of course, because with 101 transistors you could store as many Library of Congress as there are electrons in the visible universe on a disk the size of 2 square hogs for a duration of up to 3.4256 parsecs.
Unfortunately, it will take up to as many (1/98742) of year as it took in seconds for Apollo 11 to reach the moon from the launch pad to design such a hard-drive.
Why is it scientists always use weird units? I have absolutely no clue of what "the implicit information storage that corresponds to all of the hard disks made in the world this year, multiplied by the number of years the universe has been around" actually represents in bytes.
Re:Now that's a huge hard drive... (Score:2)
Re:Now that's a huge hard drive... (Score:2)
Well, let's estimate that 1 million hard drives are made each year, at an average capacity of 200gig (both figures pulled out of the air; I have no idea how many hard drives will be made this year). That's a total capacity of 0.2 billion GB/year.
The age of the universe is esti
Re:Now that's a huge hard drive... (Score:2)
Toshiba produces... (Score:2)
How many? (Score:2)
>Why is it scientists always use weird units? I have absolutely no clue of what "the implicit information storage that corresponds to all of the hard disks made in the world this year, multiplied by the number of years the universe has been around" actually represents in bytes.
6.0 X 10^8 drives x 100 GB/drive x 15 x 10^9 years x 1.1 x 10^9 bytes/GB = 9.9 x 10^29 bytes. More or less. Definitely a BFN. This should be enough for most mp3 and pr0n collections. For reference, the number of electrons in
WEBOROM - Write every, but only read one, memory (Score:2)
Say you have an algorithm that needs to store all numbers from 0 to 2^100, then the algorithm excludes sets of them until arriving at an answer. The algorithm might truly need 2^100 words of 100 bits each to proceed on a classical computer, but on a quantum computer the calculation chugs along on our i
Re:Now that's a huge hard drive... (Score:2)
Re:Now that's a huge hard drive... (Score:2)
Re:Now that's a huge hard drive... (Score:2)
No because it IS a measure of distance.
1 lightyear = 1 * the speed of light * 1 year = 9.4605284 × 1015 meters [google.com].
Just because "thespeedof" is left out, doesn't make "lightyear" a unit of time; in much the same way that when us Europeans say we want "5 kilos" of something, we actually expect 5 kilograms, and not kiloWatts or some nonsense like that.
By using 'parsec' in the context of time he was obviou
Re:Now that's a huge hard drive... (Score:2)
mean 'units of 9.81 newtons'. go figure.
clarification (Score:2)
1 Parsec = 3.08568025 × 10^16 meters
I done burned me fingers. (Score:2)
That should like a LOT of soldering.
That's weird (Score:4, Funny)
Re:That's weird (Score:2, Funny)
You might also notice that, now that you know what the whole article says, you don't know how long it took to load. If instead you had timed the page load, you wouldn't have been able to read the article.
Hrmm... (Score:5, Funny)
wow! (Score:4, Informative)
Re:wow! (Score:4, Insightful)
actually, it is evolutionary, just not revolutionary.
Re:wow! (Score:2)
Re:wow! (Score:2)
Re:QC Can't Break Existing Encryption Algorithms (Score:2)
Bad example
While this is true for any case where you're stuck doing a brute-force search, in the case of RSA there's a very, very fast algorithm for reversing the trapdoor function it uses (Shor's Algorithm, which factors the public key in far better than exponential time).
Kind of misleading... (Score:5, Informative)
Re:Kind of misleading... (Score:3, Insightful)
Tin Foil Hat Time... (Score:5, Insightful)
Quantum computing, which holds the promise of nearly unlimited processing power, secure communications and the ability to decode encrypted conversations by terrorists and others (emphasis mine)
Take special note of the word others, which should be read as everyone. The government will be falling all over themselves to support this research and inherit a technology that makes encryption virtually useless.
I'm all for advancing technology, and no doubt quantum computing will be a great leap forward. It's just a shame that our privacy will be sacrificed in the process.
Re:Tin Foil Hat Time... (Score:2)
As I understand it (Score:2)
Re:As I understand it (Score:2)
Re:As I understand it (Score:2)
Re:Tin Foil Hat Time... (Score:2)
So supposing there's some impossible miracle breakthrough and by this time next year we've all got quantum computers on our desktop. Any communications you made previous would be crackable, but everything you were doing at the time would still be secure. I can't speak for everyone, but for most places you use encryption in your daily life, the information b
Re:Tin Foil Hat Time... (Score:2)
The currently using ones (public key encryption, DES3 etc) are all developed with silicon computers in mind. While they will become obsolete with quantum computing, I will be surprised if we cannot develop something better by then...
Re:Article is misleading (Score:3, Interesting)
There is no technology which would allow two distant parties (say 1000 miles apart) to use QC to secure their communication against any evesdropping. There is nothing to suggest that this technology will ever be developed.
Now, with retransmission you could link two arbitrari
How long before I can turn my transistor radio (Score:2, Funny)
Don't hold your breath... (Score:3, Interesting)
Terrorism. (Score:2)
Why does every article about anything have to have the word "terrorist" in it, these days?
would you use your powers for good, or for awsome (Score:2)
Because if you don't immediately say that it (it, as in indefinite pronoun) is a weapon against the terrorists, someone moranic will cry that it will be used by the terrorists. And morans tend to stick together when it comes to irrational fear, so you don't want that.
Easy.. to get funding and stay out of jail (Score:2)
I you don't explicitly make the statement, you are instantly cast into suspicion..
Welcome to this 'brave new world'... Exactly what Binny boy wanted..
Re:Easy.. to get funding and stay out of jail (Score:2)
On that note..
Re:Terrorism. (Score:3, Insightful)
Re:Terrorism. (Score:2)
The guy is "Eli Yablonovitch, UCLA professor of electrical engineering, director of UCLA's Center for Nanoscience Innovation for Defense", so it'll help to get more funding (almost wrote "FUDding" there, I wonder why?).
Secure Communications ... (Score:4, Insightful)
Re:Secure Communications ... (Score:2)
no, we'll just have to figure out how to protect ourselves another way. maybe terrorism should just be viewed as a crime of opportunity. we can do lots of things to prevent the opportunity for terrorism from occurring without even infringing on people's rights. consider that proper pilot training and some secure cockpit doors could have pr
Quantum terms (Score:4, Interesting)
In the article it states: "The UCLA team succeeded in flipping a single electron spin upside down."
Considering that the term 'spin' is just a metaphor for a quantum-mechanical property that has no equivalent in our everyday experience, it makes no sense to talk about 'flipping' it, or the spin being 'upside down'.
Neat achievement though....
Re:Quantum terms (Score:3, Interesting)
You see electron spin space is a two dimensional complex space. It is tied to usual 3 dimensional real space via representation of SU(2) - so it is hard to say which direction corresponds to which.
However, if one fixes a basis in usual space one can use it to fix a particular representation of SU(2).
Furthermore, one of the basis vectors will have a particularly simple Pauli matrix corresponding to it - the direction of this vector is usually called "quantization axis".
Of
Re:Quantum terms (Score:3, Informative)
Usual 3 dimensional spin is characterized by speed (revolutions per second) and the axis the object is spinning about.
Yes, but with quantum mechanical particles, nothing is spinning. There is not one part of an electron that is rotating about another. (see my warning about 'pedantic' above!)
Flipping spin means reversing the axis - i.e. changing the direction of rotation.
But with quantum mechanical particles, there is no real 'direc
Re:Quantum terms (Score:3, Interesting)
Just for fun let me continue.. :)
What do you mean by nothing is spinning ? What does it mean to be spinning ?
I can tell when a ball spins because I can see it. But does Earth spin ? I can't see the rotation but I can infer it with tools.
Do small pieces of matter (like dust) spin ? Maybe.
Now it turns out when you look at very small pieces of matter (like particles) then the laws of nature we are accustomed to change. This is simply because we do not teach q
Re:Quantum terms (Score:3, Interesting)
Sorry, this is not right. Usual behaviour is due more to particles changing positions than to remnants of quantum behaviour.
So your point would hold if we restrict ourselves to considering only spinning that is due to bodies rotating one around another.
My point would hold if we allow idealization of solid body - i.e. an object with an intrinsic spin.
For example, you could consider
Re:Quantum terms (Score:3, Informative)
I had a Quantum hard drive before (Score:5, Funny)
I hope this drive lasts longer than the Quantumm Fireball I had.
WOW - big news... (Score:2)
Re:WOW - big news... (Score:2)
That was in the non-skimmy part of the article. It's pretty misleading, actually. A more accurate headline would have been, researchers flip the spin of an electron in a hunk of silicon that, coincidentaly, was located in an off-the-self transitor, using lots of expensive and complicated equipment.
It's a good first step, though.
Ready for Doom 4! (Score:2, Interesting)
Re:Ready for Doom 4! (Score:2)
Us back in 1994 have had "Quantum Harddrives" for So long now!! Whats taking YOU ALL SOO LONG?
Whatever you do.... (Score:2)
It might go away...
stupid lameness filter stupid lameness filter
too many caps jackasses too many caps jackasses
too bad you had to see this too bad you had to read this
Quantum computers are like women... (Score:2)
Hmm... (Score:2)
Terrorists? (Score:2, Insightful)
No, this technology is not going to be used on terrorists. It is going to be used on a combination of normal people suspected of criminal activity (ie anyone who bothers to encrypt their communications) and actual hightech criminals.
This technology will be effectively useless at stopping the terrorists we are worried about.
Nature article link (Score:2)
I only wish that CNSI will complete construction before I graduate with my Master's in CS... Seems like it will be a great facility to do research on this sort of thing. Oh well, there's always CENS
- shadowmatter
Re:Got a Free Link? (Score:2)
Oh well... Leave me your e-m
boo. Article gets a thumbs down. No, the finger. (Score:2, Interesting)
I was willing to forgive a little hype until the idiocy about terrorists. Decided maybe I was just cranky, then read:
While flipping a single electron was difficult, detecting that they had actually done so proved even harder. "We couldn't tell whether it was flipping," Jiang said. "It was like looking for a needle in a haysta
Implicit Disinformation (Score:3, Interesting)
Not really so close to quantum computing (Score:2)
Creating and measuring the quantum state of a single particle is *not* new. Or that hard. The neat thing is that they did it with a commercial transistor.
Oh, and some sort of fridge that goes to -400 F.
The really hard part in quantum computing (as far as I can tell) is (a) creating and (b) maintaining a coherence between many particles.
The problem is that useful coherences between particles are *very* easi
Name that profession (Score:3, Funny)
I can see it now.... (Score:4, Funny)
schrodinger's Screen Saver (Score:2)
Intro to Quantum Computing (Score:3, Informative)
Quantum computing at room temp? NOT!!! (Score:2)
Re:Hong Wen Jiang also admits (Score:2)
Re:Jamming communications? (Score:2)
Entanglement may or may not come into play. Depends on what you're doing, because you can just use the quantum computer to do calculations and then send the info over more traditional means. This removes having to entangle many electrons, then put them in separate devices,
Re:Why does anyone believe this works... (Score:2, Insightful)
This would be an accurate description, only it's not.
If you perform the double-slit experiment with twenty humans, a canon, and segments of brick walls, you don't wind up with an interference pattern. With electrons, you do. Also, factoring with quantum computers has been successfully performed, so we know it works.
If it makes you feel better, it isn't just a matter of treating statistics as physical reality. It's more a matter of realizing that at certain small sizes, 'matter' isn't exactly ma
Re:Why does anyone believe this works... (Score:2)
Awesome! A crackpot! (Score:2)
When you say things like this you sound like the guys trying to sell "Zero Point Energy" and the like.
Go read a book. For starters, I recommend Griffiths.
Muerte
Re:How long? (Score:2)
Crackpot alert.... (Score:2)
Re:Crackpot alert.... (Score:2)
Your opinion matters to me because...
Re:Quantume Computing = Fraud (Score:2)
It's a quantum leap, of course.