Slashdot Mirror
IBM Touts Quantum Computing Breakthrough
Lucas123 writes "IBM today claimed to have been able to reduce error rates and retain the integrity of quantum mechanical properties in quantum bits or qubits long enough to perform a gate operation, opening the door to new microfabrication techniques that allow engineers to begin designing a quantum computer. While still a long ways off, the creation of a quantum computer would mean data processing power would be exponentially increased over what is possible with today's silicon-based computing."
And people keep telling me IBM isn't innovative and cutting edge anymore. [/Sarcasm]
1) Repeated news about being able to perform some operation with a tiny number of qubits do not suggest that it is probably true that a useful quantum computer of practical size can be built;
2) It wouldn't mean data processing power would be "exponentially increased", but that certain algorithms could be executed asymptotically faster.
QC remains a second rate branch of mathematics for computer science types who don't want to apply themselves to less glamorous problems in the more mature and challenging fields of classical computing. For engineers, it's still in the nuclear fusion stage: kinda just possible in the right conditions, but under no conditions shown useful.
data processing power would be exponentially increased over what is possible with today's silicon-based computing.
Please, please, please stop misusing the word "exponentially". It just means that something is increasing (or declining) at a constant rate, which is practically the opposite of what is meant here.
Never mind the banter, where's my nano Mac? Show us your sugar cube sized z-series mainframe! :0)
The purpose of existence is to make money.
I have become increasingly disappointed with Slashdot’s lack of good content. This particular story about quantum computing is actually a pretty good one, but they're becoming fewer and farther between. So, I’ve reached the point where I’m going to delete my Slashdot bookmark. Any suggestions for a good replacement tech news website?
The Economist had an interesting article a couple days ago.. at least it's interesting if you don't really know the details of quantum computing:
Quantum computing: An uncertain future
Each extra qubit in a quantum machine doubles the number of simultaneous operations it can perform. It is this which gives quantum computing its power. Two entangled qubits permit four operations; three permit eight; and so on. A 300-qubit computer could perform more concurrent operations than there are atoms in the visible universe.
Actually, this is a correct use. Some algorithms on quantum computers are exponentially faster than the best known classical algorithms. For example, estimating a Gauss sum http://en.wikipedia.org/wiki/Gauss_sum scales exponentially in time, but the most efficient quantum algorithms are bounded by a polynomial. So exponential speed up is a valid use of the term here.
The software goons find a way to bring even that hardware to a crawl...
I find that to be a terrible explanation. What he said: "For each qubit you double the number of states you can be in at the same time." is also true for normal bits. Huh? Here is a better explanation: http://en.wikipedia.org/wiki/Qubit
does it run GNU/Linux ?
For conventional computers, as soon as you have "and" and "not" in gate-form, you can do everything, as you can just connect them together. For quantum computers that is not true, as all elements performing the complete computation need to be entangled the whole time.
IMO, there is now reason to believe that the real-world scalability of quantum computers is so bad that it negates any speed advantage. It seems the complexity of building a quantum computer that can do computations on inputs of size n is at least high-order polynomial or maybe exponential in n. That would explain why no significant advances have been made in keeping larger quantum computing elements entangled in the last 10 years or so and no meaningful sizes have been reached.
Keep in mind that, for example, to break RSA 2048, you have to keep > 2048 bits entangled while doing computations on them. And you cannot take smaller elements and combine them, the whole > 2048 bits need to represent the input all must be entangled with each other or the computation does not work.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
I dont know anything better, and you will be dissapointed with scientific journals too, so get used to it
I'm positive, don't belive me look at my karma
Any suggestions for a good replacement tech news website?
You'll have to clarify your definition. If you want "tech news" as in news about "hard science" tech there are places like arxiv.org or PLOS for bio stuff. My best guess for IT type primary sources is maybe the debian-announce mailing list or the daily SANS ISC diary? There are no primary source places that I'm aware of with social media type features, not /. certainly not on G+ or whatever.
If by "tech news" you mean news about other tech news sites, if you prefer a weekly format thats "this week in tech" and some other twit and rev3 shows and/or at least some /. articles. One important filter consideration is I don't want to go to a site exclusively populated with "txt speak" and/or total noobs. "Hay guys I just heard of this unix port 4 my pc its called linux has any1 else hear herd of it????!?". Sorry I don't want to see that. I haven't been a noob to this computer thing since 1981 or to the internet since the (very) late 80s.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
I wonder if IBM will be upgrading Watson with a Quantum computer brain. Won't be long now before they invent HAL.
-- By all means let's be open-minded, but not so open-minded that our brains drop out.
I miss the days when IBM actually made PC's they were always rock solid. You could beat someone to death with one of there laptops and after wiping the blood off it it would still work...
has any1 else hear hurd of it????!?
FTFY.
Apparently wizard is not a legitimate career path, so I chose programmer instead.
Ok, IANAP, but, like many slashdotters, am interested in all things science and especially quantum mechanics. Please explain, if you may, this contradiction, because I've been unable to find a good explanation in anything I've read so far.
... Does this mean that, in 2^250 - 1 universes, the scientist will commit suicide, or get fired, (because obviously, the other solutions are uncorrect) ?
If we consider the many worlds interpretation to be viable, from what I understand :
- when a scientist will start up the very first quantum computer for the first time -- say, a big 250 qubit computer -- and will test it against a big cypher or whatever, 2^250 universes will participate in the process
- after the quantum collapse, the unique solution will be found, the cypher will be cracked and OUR scientist in OUR world will open a bottle of champagne and congratulate with their team
I took a class on Quantum computing, and studied many specific QC algorithms, so I know a little bit about them.
Quantum Computers are not super-computers. On a bit-for-bit (or qubit-for-qubit) scale, they're not necessarily faster than regular computers, they just process info differently. Since information is stored in a quantum "superposition" of states, as opposed to a deterministic state like regular computers, the qubits exhibit quantum interference when mixed with other qubits. Typically, your qubit starts in 50% '0' and 50% '1', and thus when you measure it, you get a 50% chance of it being one or the other (and then it assumes that state). But if you don't measure, and push it through quantum circuits allowing them to interact with other qubits, you get the quantum phases to interfere and cancel out. If you are damned smart (as I realized you have to be, to design QC algorithms), you can figure out creative ways to encode your problem into qubits, and use the interference to cancel out the information you don't want, and leave the information you do want.
For instance, some calculations will start with the 50/50 qubit above, and end with 99% '0' and 1% '1' at the end of the calculation, or vice versa, depending on the answer. Then you've got a 99% chance of getting the right answer. If you run the calculation twice, you have a 99.99% chance of measuring the correct answer. However, the details of these circuits which perform quantum algorithms are extremely non-intuitive to most people, even those who study it. I found it to require an amazing degree of creativity, to figure out how leverage quantum interference constructively.
But what does this get us? Well it turns out that quantum computers can run anything a classical computer can do, and such algorithms can be written identically if you really wanted to, but doing so gets the same results as the classical computer (i.e. same order of growth). But, the smart people who have been publishing papers about this for the past 20 years have been finding new ways to combine qubits, to take advantage of nature of certain problems (usually deep, pure-math concepts), to achieve better orders of growth than possible on a classical computer. For instance, factoring large numbers is difficult on classical computers, which is why RSA/PGP/GPG/PKI/SSL is secure. It's order of growth is e^( n^(1/3) ). It's not quite exponential, but it's still prohibitive. It turns out that Shor figured out how to get it to n^2 on a quantum computer (which is the same order of growth as decrypting with the private key on a classical computer!). Strangely, trying to guess someone's encryption key, normally O(n) on classical computers (where n is the number of possible keys encryption keys) it's only O(sqrt(n)) on QCs using Grover's algorithm. Weird (but sqrt(n) is still usually too big).
There's a vast number of other problems for which efficient quantum algorithms have been found. Unfortunately, a lot of these problems aren't particularly useful in real life (besides to the curious pure-mathematician). A lot of them are better, but not phenomenal. Like verifying that two sparse matrices were mulitplied correctly has order of growth n^(7/3) on a classical computer, n^(5/3) on a quantum computer. You can find a pretty extensive list by googling "quantum algorithm zoo." But the reality is that "most" problems we face in computer science do not benefit from quantum computers. In these cases, they are no better than a classical computer. But for problems like integer factorization, bringing the compute requirements down to polynomial time isn't just faster: it makes a problem solvable that wasn't before.
Unfortunately [for humanity], there is no evidence yet that quantum computers will solve NP-complete problems efficiently. Most likely, they won't. So don't get your hopes up about solving the traveling salesmen problem any time soon. But there is still a lot of cool stuff we can do with them. In fact, the theory is so far ahead of the technology, that we're anxiously waiting for breakthroughs like this, so we can start plugging problems through known algorithms.
Edit : the other solutions are incorrect
(In the other worlds, I'm better at learning foreign languages).
This news story appears the day after IBM laid off a number of engineers in STG. (system and technology group, the part of the company that works on operation systems and hardware like Power, blades, Z, etc)
Not that IBM would be attempting to deflect any negative news stories which might range from the very tight lipped control on number of employees let go, forbidding those employees let go from talking to the press or lose their severance pay, current number of employees in the US, brain drain of engineers leaving cause impacts in product creation.
Stay classy IBM.
As soon as the 'decryption orders' stop and Truecrypt encrypted volumes are being entered into evidence decrypted, IBM will be on to something.
I always thought the contraction was "qubit" for "Quantum Bit".
Is "quibit" an accepted variant spelling, and, if so, where does the extra letter "i" come from?
Hollywood, Television, has become the dream machine. We need to take that back; each of us is a Dream Machine
I've always been partial to The Register (www.theregister.co.uk) which is snarky and British (and the home of the BOFH) and to Ars Technica (www.arstechnica.com) which tries to focus on actually writing interesting articles about news rather than just linking to things.
There is often some overlap between themselves and /. but it's not as bad as you'd expect.
Except that the Register is even more populist than Slashdot and written by mediocre hacks - Slashdot at least doesn't pretend to be staffed by journalists, merely linking elsewhere. And it's only "home" to the BOFH in the sense that the Aussie sold out to them ("he's a BOFH, what do you expect?").
Ars technica has the occasional highly knowledgeable contributor but usually gives me the uncomfortable sense of an editorial belief that the more you write, the more insightful and relevant your piece is.
There are three honest sources of STEM news:
(1) Peer-reviewed journals;
(2) progress reports by practitioners;
(3) Chatty, informal summaries of press releases, word of mouth and items in (1) and (2).
Items in (3) rquire you to either go to (1) or (2) or examine the subject yourself to obtain an in-depth analysis.
Outlets which try to position themselves between (2) and (3) are a waste of time, also likely to reinforce any of your existing biases since they're never neutral.
No. Quantum computing works whether or not MWI is correct. And it doesn't have to do with quantum suicide. In an MWI situation, the vast majority of universes will get the same (correct) result. Essentially, the different universes cooperate with each other before the split off. This isn't quite correct (in MWI there are really discrete universes but rather part of a continuum, and there are a lot of other subtleties involved).
BASF, we don't make the things you use.
We make the things you use BETTER.
That was the commercial I remember for several years.
I suppose they couldn't live up to this promise any more since they changed it to We don't just make chemicals, we make chemistry
"...also likely to reinforce any of your existing biases since they're never neutral."
I thought we were talking about science content? Why would biases be relevant?
Independently reproduceable results rule; soundbites drool.
Real World Technologies is worth mentioning too. It's a high-quality, rarely updated site involving mostly CPU/GPU/APU type stuff.
i hate how there are all these articles about how they finally have these break throughs! there was over a dozen alerts for IBM this morning and this record breaking discovery. DWAVE systems of BURNABY BRITISH COLUMBIA CANADA! has made a functional quantum computer chipset for over a year! They are already building chips at 500+ qubits with there first machine being sold to LOCKHEED MARTIN for $10 MILLION. they are already establishing a quantum computing cloud to allow access to developers and organizations to perform specific calculations. all these computer companies either dont read the news or are just fragrantly disregarding any level of honest disclosure. it's disgusting! its a huge breakthrough AGREED. made by another company!!!! get over it! TRY AND CATCH UP ALL YOU LIKE.. GOOD FOR YOU! BUT DONT TRY AND FOOL PEOPLE INTO THINKING YOU ARE THE PIONEER AND INDUSTRY LEADER WHEN YOU ARE NOT!
Just one and he kept shouting things about peanuts.
"On a bit-for-bit (or qubit-for-qubit) scale, they're not necessarily faster than regular computers, they just process info differently."
Thank you. I have been trying and failing (in tweets @DrEpperly) to explain the concept you describe very succinctly. I have a telecommunications background so we just think of it as having two channels...sort of like the old 'dual-mode' phones...
When you get published saying this please send me a link ;)
Thank you Dave Raggett
Everybody who's is interested in advances of quantum computation should have a look at this publication
It was uploaded to arXiv today and shows another implementation of Shor's algorithm in a four-qubit system.
Althought their fidelity is not as high as the one claimed by IBM, I do think that their technology is a little bit more advanced.
That's not how quantum computers work, despite of what you might have read in science popularization articles. Quantum algorithms don't work like classical algorithms work, but "doing all possibilities at once". That wouldn't work because of the contradiction you described -- once you measure the result, all the other "possibilities" go away.
Quantum algorithms work by not only solving the problem, but also shifting the probabilities of the qubits in such a way that, when you measure it, you get a very high probability of measuring the "right" answer. For example: in the quantum part of Shor's algorithm, you start with a lot of qubits that have 50% probability of being 0 and 50% of being 1, and after doing the computation, you end up with the qubits with a very high probability of having in the "correct" value. This works because the probability of being right can be as high as you want -- you can set things up so that the probability of being wrong is the same as that of an asteroid hitting the computer while it's calculating, for example.
That's why it's very hard to come up with quantum algorithms. For a lot of problems, it's doubtful that it's even possible to have a quantum algorithm that's much better than classical algorithms. For example, most quantum computer scientists think that quantum computers will never be able to solve NP-complete problems much faster than classical computers.
Promises of quantum computers seem to be suffering from the fusion syndrome. Fusion has been "only 20 years away" for the last 40 years. :P
Maybe it's more a reflection of the changes in the tech industry than in the site.
Check your premises.
More than Anonymous Cowards.
The Tao of math: The numbers you can count are not the real numbers.
You have 2048 randomly entangled bits.
Somebody on the other side of the world has the matching pair of 2048 randomly entangled bits.
Not useful for communication per-se if you can't influence them, but if you could *READ* them without influencing them, they'd be darn spiffy for an encryption key or seed shared between two parties.
Simple XOR encryption would be awesome so long as you both have synchronized reading of the encrypted bits. Take message, XOR it against the encryption key, send to recipient, recipient XOR's it against same encryption key and gets the encryption message.
Next chunk of data, you both have a new key courtesy of your shared entangled bits.
The issue again being that you'd need to have:
a) Bits that change state randomly on an interval that fits your data throughput
b) a very fine synchronization between how often the bits change state and when you send/receive data, so that both parties are using the same key/mask.
I simply do not accept "god" is prepared to let us little pissants scale qbits to our hearts content at a price we are able to afford. We have no evidence to support the assumption coherence reinforcement schemes can scale.
I'm sure with enough R&D these systems will become cheaper and prove very useful in solving a wide range of hard problems.
The extraordinary codebreaking claims and all related rumblings about solving problems practically impossible for a normal computer to solve are right up there with bigfoot, aliens, zedpm's, flux capacitors and sadly hoverboards.
I'll believe it when I see it.
mostly, MWI is bullshit.