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Programmable Quantum Computer Created

Soulskill posted more than 4 years ago | from the four-out-of-five-ain't-bad dept.

Science 132

An anonymous reader writes "A team at NIST (the National Institute of Standards and Technology) used berylium ions, lasers and electrodes to develop a quantum system that performed 160 randomly chosen routines. Other quantum systems to date have only been able to perform single, prescribed tasks. Other researchers say the system could be scaled up. 'The researchers ran each program 900 times. On average, the quantum computer operated accurately 79 percent of the time, the team reported in their paper.'"

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132 comments

79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30237808)

The researchers ran each program 900 times. On average, the quantum computer operated accurately 79 percent of the time, the team reported in their paper.

20% of the time it got it wrong, and 1% of the time, someone looked in the box and it wasn't there. 79% accurate. That's pretty useless. I've got a pair of dice that can do just as badly.

Re:79% accuracy ... (2, Funny)

Anonymous Coward | more than 4 years ago | (#30237858)

My dice are 100% accurate. I ask them for a random number, and every time that is what they return.

Re:79% accuracy ... (1)

Fizzl (209397) | more than 4 years ago | (#30237890)

int rand()
{ return 3; } //Chosen with a fair dice roll

(Old joke, yeah.)

Re:79% accuracy ... (1, Funny)

Anonymous Coward | more than 4 years ago | (#30237904)

Someone will put linux on it, and it will be able to crack RSA, but people won't be able to figure out how to get their printers to work with ti.

Re:79% accuracy ... (1, Funny)

Anonymous Coward | more than 4 years ago | (#30237944)

Someone will put linux on it, and it will be able to crack RSA, but people won't be able to figure out how to get their printers to work with ti.

...Or their keyboards.

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30238242)

My dice are 100% accurate. I ask them for a random number, and every time that is what they return.

I can fix that for you with a bit of sandpaper (dice that are slightly sanded on one or more faces are called"flats [metal-express.net] ", and come up non-random).

Re:79% accuracy ... (4, Insightful)

Timothy Brownawell (627747) | more than 4 years ago | (#30238042)

79% accurate. That's pretty useless.

Not useless at all, just have it solve the same problem 5 or 15 times and go with the answer that it gives most often. Plus, for some problems it's much easier to verify an answer than to come up with it -- for those problems, just pair it with a normal computer to check the answers, and keep trying until it says the answer is right.

Re:79% accuracy ... (-1, Offtopic)

tomhudson (43916) | more than 4 years ago | (#30238198)

79% accurate. That's pretty useless.

Not useless at all, just have it solve the same problem 5 or 15 times and go with the answer that it gives most often.

That's TOTALLY moronic. That's like saying "get 5 or 15 people to guess your birthday and go with the answer that it gives most often."

Go and ask 510 Americans to point to New York on a map [nationalgeographic.com] , and go with the answers that they give the most often.

Despite nearly constant news coverage since the war there began in 2003, 63 percent of Americans aged 18 to 24 failed to correctly locate the country (Iraq) on a map of the Middle East. Seventy percent could not find Iran or Israel.

Nine in ten couldn't find Afghanistan on a map of Asia.

And 54 percent were unaware that Sudan is a country in Africa.

Remember the December 2004 tsunami and the widespread images of devastation in Indonesia?

Three-quarters of respondents failed to find that country on a map.

A third of the respondents could not find Louisiana, and 48 percent couldn't locate Mississippi on a map of the United States, even though Hurricane Katrina put these southeastern states in the spotlight in 2005.

And what about India, which features prominently in the job-outsourcing debate? Forty-seven percent of young Americans were unable to locate where their jobs may go on a map of Asia

Heck, many Americans can't even find the USofA [huffingtonpost.com] on a map.

"That thing definitely looked familiar," said autoworker and father of three Ed McConnell. "And my gut told me there were probably a whole bunch of Americans there. So I had to go with 'Iraq.'"

Good thing he's not in charge of the big red button - he'd nuke you'all.

Meanwhile, the Department of Homeland Security sees the Gallup/Harris poll results as a blessing in disguise. According to Secretary Michael Chertoff, the nation would be better off if these numbers skewed even higher.

"Personally, I believe if fewer people in this world could spot America on a map, we'd have a much better chance of avoiding national tragedies like 9/11," said Chertoff. "You can't attack a country you can't find."

How stupid can you get?

Well, turns out even stupider than that:

Asked for the name of the U.S. capital, those polled placed Washington, D.C., fifth behind "Minneapolis-St. Paul," "Mount Rushmore," "America City," and "Whitewater."

So, according to your "go-with-the-flow" theory, the capital of the US is Minneapolis-St. Paul.

Re:79% accuracy ... (1)

billakay (1607221) | more than 4 years ago | (#30238294)

You might want to look up the randomized computational complexity class BPP. There is 2/3 - 1/3 split on when it answers correctly. I believe that it answers correctly 2/3 of the time, and the other 1/3 time is indeterminate. All you need to do is run it a few times (these algorithms are very fast, and average the results. The summation of these attempts very quickly approach many nines of accuracy after a relatively short number of attempts. In fact, before the (relatively) recent discovery that primality testing is in P (the discovery of a deterministic poly-time algorithm for testing whether a number is prime), the best algorithm was in BPP, and in fact, that is the algorithm that is mostly used today because of it's speed.

Re:79% accuracy ... (1)

kheldan (1460303) | more than 4 years ago | (#30239428)

If this is the way these systems work, and since they're so tiny, wouldn't it make sense to build them as triple-redundant (or more) all running the same exact routines, and take the majority answer? Or perhaps have a cluster of them running in parallel the same routine X number of times and take the majority answer from that?

Re:79% accuracy ... (0, Insightful)

Anonymous Coward | more than 4 years ago | (#30238312)

you noticed that the article you are quoting is satire right?

Re:79% accuracy ... (1)

roguetrick (1147853) | more than 4 years ago | (#30238870)

I hope because of that his post is satire.

Re:79% accuracy ... (0, Flamebait)

tomhudson (43916) | more than 4 years ago | (#30239362)

... you notice that it's backed up by similar interviews on video all over the net? Americans who think that the US invaded Israel, who point to Australia and think it's Iraq, etc...

Just because it's satire doesn't mean it isn't true - satire is used to expose truth, not hide it.

Re:79% accuracy ... (1)

wumingzi (67100) | more than 4 years ago | (#30240132)

.. you notice that it's backed up by similar interviews on video all over the net? Americans who think that the US invaded Israel, who point to Australia and think it's Iraq, etc...

I'm not going to stand up for Americans' knowledge of the world beyond their borders (of their country or their county), but remember that the interviews you often see on the net are the result of hours of interviews cooked down to the 4 minutes which are the funniest and most outrageous.

The reality IS bad, don't get me wrong, but it's not THAT bad!

Re:79% accuracy ... (5, Funny)

Jahava (946858) | more than 4 years ago | (#30238324)

That's TOTALLY moronic. That's like saying "get 5 or 15 people to guess your birthday and go with the answer that it gives most often."

Are people accurate 79% of the time? In the examples you gave? Then no, it's not like that at all.

How stupid can you get?

Many thanks for demonstrating!

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239166)

There were examples where people had the same (lousy) accuracy as this. Try reading the links instead of just looking at the portions I quoted for brevity.

Re:79% accuracy ... (1)

Anonymous Coward | more than 4 years ago | (#30239426)

Your links is interesting in one sense but completely irrelevant to the issue at hand. And, frankly, the birthday thing was YOUR example, and it was completely wrong, so maybe you shouldn't have made that your example? You can't possibly castigate somebody for not inventing an argument you didn't make, especially a bad one, based on an irrelevant link you provided.

From looking at the link, it's more like asking 6-17 people what country is the world's largest consumer of oil, and going with the most common answer. Which is an effective tactic that is likely to be right. For birthdays? No amount of guessing is going to help, because your chances of selecting each wrong answer are equal to your chances of selecting the right answer. These statistics only work when the chances of getting the answer right are higher than the chances of choosing any particular wrong answer, but then they DO work.

At 79% accuracy, repeating independent trials 5 times and taking the most common answer gives you >90% accuracy (you have to be wrong 3 times to no longer guarantee accuracy, and that's 21% cubed, or 0.009261%, times 5 choose 3, or 10, + a bit for being wrong 4 or 5 times -- and if the incorrect answers don't match you're still getting the right answer, so the accuracy is a bit better than that on anything but a binomial question). Repeating 15 times brings the error down to ~2%, and again, if the "wrong" answers are evenly distributed among a large number of alternatives, then the error is now a very, VERY small number, far lower than 1%. Eventually, repeated trials make the chances of error in a traditional computer from phenomena like spontaneous bit-flipping and self-interference even in binomial cases.

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239508)

Note the article - hundreds of different functions were tested, with an overall accuracy of 79%. How are you intending to build more than a trivial piece of code when you have 79% accuracy from each function, on average? The fact is, the more function calls you add, and the more functions you add, the more likely that at least one will be wrong - and then the errors will, of course, cascade, since now you already have bad data for the next fuction, and it's highly unlikely you'll get just the right error to cancel it out.

The more complex the program, the more likely that you'll never get the same answer twice over n runs ... it's still useless at this point - the only quantum computing device that has the necessary power to correct for bad inputs is your brain, and that's because it doesn't need to find "the right" answer - just one good enough to survive.

Re:79% accuracy ... (0, Offtopic)

dem0n1 (1170795) | more than 4 years ago | (#30238334)

So, according to your "go-with-the-flow" theory, the capital of the US is Minneapolis-St. Paul.

Does that mean Al Franken is the President then?

Re:79% accuracy ... (0)

Anonymous Coward | more than 4 years ago | (#30238396)

How stupid can you get?

Now imagine that the problem that this computer solves is extremely difficult, and would take billions of years to solve on a conventional computer.

Suddenly it doesn't sound so stupid anymore, eh?

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239378)

Now imagine that the problem that this computer solves is extremely difficult, and would take billions of years to solve on a conventional computer.

Suddenly it doesn't sound so stupid anymore, eh?

Problems have a way of falling down a lot quicker than you'd think. When they started sequencing the human genome, they thought it would take 100 years. Gee, how time flies - it sure didn't seem like it took 100 years.

There's almost always a better algorithm if you look at a problem long enough.

Re:79% accuracy ... (1)

Imrik (148191) | more than 4 years ago | (#30240720)

These aren't new problems like the human genome sequencing was, we've been looking at these problems for quite a while now. While we occasionally do get a slightly better algorithm it's still the same order of complexity.

Re:79% accuracy ... (4, Informative)

chhamilton (264664) | more than 4 years ago | (#30238398)

No, it's actually a perfectly reasonable idea. Consider running the device (n+m) times. The probability of it being right n times and wrong m times is given by:

P(n,m) = (n+m)!/n!/m! 0.79^n 0.21^m

Now consider the probability of it being right (majority has the right answer) out of 2n+1 trials. This is the given by:

S(n) = sum( P(n+1+i,n-i), i=0..n )

This can be simplied to a closed form using Legendre and gamma functions, but that's kind of messy and it's far easier to just plug in values and do the summation. As it turns out, doing the experiment 15 times and taking the majority (plugging 7 into S(n)) will give you the correct answer 99.4% of the time. Doing things 35 times gets you to five nines of accuracy... completely reasonable in my books.

Re:79% accuracy ... (0, Troll)

tomhudson (43916) | more than 4 years ago | (#30239204)

I want 1005 accuracy. I don't want 2+2 = 3.9999999999882 on average after 100 runs, then having it fail every time when I do an if(2+2) == 4).

Sure, I could use a delta, and then make sure it's under that, but then you have the accumulation of errors and tolerances.

Take a barrel of shit, add a cup of wine, you still have a barrel of shit.

Take a barrel of wine, add a cup of shit, you have a barrel of shit.

A failure rate of 21% is bad business. Ask Microsoft wrt the XBox RRofD

Re:79% accuracy ... (1)

Your.Master (1088569) | more than 4 years ago | (#30239456)

You can't ever have 100% accuracy, ever. Nothing you do can ever change that.

This isn't talking about " 2+2 = 3.9999999999882 on average after 100 runs". The given algorithm is 2+2 = 4, with 99.99999999% confidence, determined after 100 runs. Which is what you ALREADY get with non-quantum computers, because nothing is 100%.

Quantum computing is not like floating-point computing. It gets an exact answer, with any individual run having potentially shitty accuracy, but accuracy can be fixed. The errors and tolerances don't accumulate; it's confidence that accumulates with this sort of algorithm.

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239650)

The problem is you want to look at the accuracy of the entire system, not just one line. In a 100,000 line program, making multiple recursive calls to many functions, 21% errors in each function will mean you'll pretty much never get the same answer twice between runs, whereas conventional hardware is pretty darned deterministic.

It's not like FP arithmetic, but the errors still do accumulate, because bad output from one step becomes bad input for the next - the errors accumulate aggressively.

Re:79% accuracy ... (1)

Bloodoflethe (1058166) | more than 4 years ago | (#30240220)

You are acting like they will only make one calculation and go with it. You keep talking about this 21%, when the accuracy measurements, (until they find a way to make it more accurate) would require confidence testing on the numbers before input into as an answer into your program. Not that I think they'll be happy with doing it that way. But for now, it'll give you the accuracy necessary to get the job done right.

Re:79% accuracy ... (0)

Anonymous Coward | more than 4 years ago | (#30239750)

Still, we're not talking about a comercial device. Not yet, at least. When transistors were first conceived, you can be damn sure that no one could make a completely accurate numerical computer out of it. So it's just a matter of time.

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239858)

Still, we're not talking about a comercial device. Not yet, at least. When transistors were first conceived, you can be damn sure that no one could make a completely accurate numerical computer out of it. So it's just a matter of time.

Transistor radios were out 5 years (1952) after the transistor was invented (1947). Between 1955 and 1957 several companies were selling fully-transistorized calculators and computing devices.

I doubt we'll be seeing fully-quantized computers in 10 years.

Re:79% accuracy ... (1)

WCguru42 (1268530) | more than 4 years ago | (#30238430)

79% accurate. That's pretty useless.

Not useless at all, just have it solve the same problem 5 or 15 times and go with the answer that it gives most often.

That's TOTALLY moronic. That's like saying "get 5 or 15 people to guess your birthday and go with the answer that it gives most often."

That would actually be quite impressive, I don't know of a computer that can guess a random value, such as a birthday, with 79% accuracy. And everything else in your post, though I've heard most of it before, just makes me feel sad for the condition of the USA.

Re:79% accuracy ... (1)

roguetrick (1147853) | more than 4 years ago | (#30238896)

His entire post was based on a satire article. The fact that so many people took it seriously makes me happy I'm better than those elitists! Wait...

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239232)

My point is simple - we laugh at the American citizens who think the United States is a foreign country and can't find it on the map, but we take :quantum computing" seriously when it has equally laughable results. Until it's accurate, the "computing" part should be removed. It might be quantum, but it ain't computing, because it simply doesn't compute (pun intended :-).

Next buzzword bingo article - "Cloud quantum computing at the LHC makes baguette disappear 50% of the time! Latest theory is toast! Physicists blame the French. EU demands youtube videos be removed because they make fun of scientists!"

Re:79% accuracy ... (1)

Captain Segfault (686912) | more than 4 years ago | (#30238744)

That's TOTALLY moronic.

I've been seeing this a lot lately.

Is responding to objectively correct posts with a combination of insults and an invalid argument the current fashion in troll-land, or has slashdot been invaded by twelve year old non-nerds? In good faith I'll assume the latter, leaving me with a stupid question: how did a twelve year old get a five digit UID?

Re:79% accuracy ... (1)

roguetrick (1147853) | more than 4 years ago | (#30238908)

Your assumption is TOTALLY moronic. Creating an emotional argument has ALWAYS been the most effective tactic in trolling.

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239346)

Think about it - the posters' premise was that take a sample of 5 to 15 times, and go with the majority answer. I pointed out some of the hazards of that. There are many more, all obvious to anyone who wants to think for a few minutes.

Let's say we do a calculation, 2+2. We do it 5 times. If it's only right 79% of the time, every once in a while, we'll get a sample of 5 where the majority is not 4 ... So, if we have a condition like if (2+2 == 4), it will fail once in a while, in a non-predictable way. So now, instead of having just a 79% accuracy, you have a cascade of inaccuracies. If every line of your code has a 1 in 5 chance of failing, anything more complicated than trivial programs like "goodbye, world!" will fail more than they will succeed.

Think of it - if you have 100 lines of code, with a chance of 1% error every time any one line was run, your program will almost always give wrong output.

It's like in the old days of tube computers - sure, a tube might last 10,000 hours - but with 10,000 tubes, you'd better make sure your program didn't require a week to run - on average, at least one tube would burn out long before then.

Re:79% accuracy ... (0)

Anonymous Coward | more than 4 years ago | (#30239586)

I don't think you understand what 79 percent accuracy means.

79 percent accuracy means that 21% of the time, the answer is wrong. But if you do the same answer 5 times, then the percentage of the answer being wrong gets much smaller. This is simple probability stuff.

0.21 * 0.21 * 0.21 * 0.21 * 0.21 = 0.0004084101. That's 4 hundreths of a percent chance of it being inaccurate. This number gets hugely smaller with an increasing sample size. For example 15 tries gets you a 0.000000000068. I don't know, but that seems pretty darn good, to me.

-XcepticZP

Re:79% accuracy ... (1)

tomhudson (43916) | more than 4 years ago | (#30239722)

And if you have code that is non-trivial, then you're going to have more than one function call. Say you have code that executes a few billion function calls (not too hard to imagine - your computer does it every day just surfing the web and drawing pretty icons on-screen). Your 4/10000 error for each function call after picking the median of 5 iterations means that we can pretty much guarantee that every run of the overall program for the rest of your life will be in error. So, you say, increase the number of iterations at each step. The problem is, the number of iterations needed to keep the overall error rate down increases rapidly with each new function call because errors do accumulate for non-trivial programs.

Re:79% accuracy ... (0)

Anonymous Coward | more than 4 years ago | (#30240382)

That second link, for the huffingtonpost article. I guess you missed this at the top:

"Editor's note: This post is a satire."

This makes your accuracy 50%, still not as good as the quantum computer. Better luck next time.

Re:79% accuracy ... (2, Informative)

Frequency Domain (601421) | more than 4 years ago | (#30238592)

79% accurate. That's pretty useless.

Not useless at all, just have it solve the same problem 5 or 15 times and go with the answer that it gives most often. Plus, for some problems it's much easier to verify an answer than to come up with it -- for those problems, just pair it with a normal computer to check the answers, and keep trying until it says the answer is right.

One of the classic examples of that last one is prime factorization. In general it's very hard to come up with the two primes that were multiplied to create a very large number, but if the quantum computer coughs up a candidate it's downright trivial to check whether that's a solution.

Re:79% accuracy ... (1)

RudeIota (1131331) | more than 4 years ago | (#30238656)

There's still room for error there though, and that is simply unacceptable based upon how we use our computers today.

This means that quantum-based processor will either become useful for a certain niche (something that doesn't require precise results) or we'll find a way to make them useful for everyday stuff... like outfitting classical processor technology with quantum capabilities to solve specific types of problems more efficiently.

Re:79% accuracy ... (1)

LKM (227954) | more than 4 years ago | (#30238804)

There's still room for error there though, and that is simply unacceptable based upon how we use our computers today.

Well, no. Computers can always be wrong. Repeat the calculation often enough, and you'll be better than your average PC. Besides, as RudeIota notes, sometimes the calculation is hard, but verifying the result is trivial (that is often the case in cryptography, for example). In those cases, you can just repeat the calculation until it's correct.

Re:79% accuracy ... (1)

Timothy Brownawell (627747) | more than 4 years ago | (#30239016)

There's still room for error there though, and that is simply unacceptable based upon how we use our computers today.

This is why everybody uses only ECC memory in their desktop machines and all filesystems in common use support checksumming for data integrity.

Re:79% accuracy ... (1)

tlhIngan (30335) | more than 4 years ago | (#30240076)

There's still room for error there though, and that is simply unacceptable based upon how we use our computers today.

This is why everybody uses only ECC memory in their desktop machines and all filesystems in common use support checksumming for data integrity.

Or uses floating-point hardware. Regardless of how many bits you use, floating-point computations are always approximate (mostly because the range of numbers that can be represented is larger than the number of possible numbers a given bit length can represent).

Hell, these computers might be more accurate, since there's a number of floating point operations you can do where the precision drops sharply because of the way it works.

Re:79% accuracy ... (1)

mugurel (1424497) | more than 4 years ago | (#30238958)

So I guess in the near future we will be seeing things like:

>>> 1 + 1

2 (p < .001)

Re:79% accuracy ... (1)

Device666 (901563) | more than 4 years ago | (#30239390)

The programmable quantum computer is 100% accurate all the time, it always prints 42.

Re:79% accuracy ... (1)

volpe (58112) | more than 4 years ago | (#30240768)

Plus, for some problems it's much easier to verify an answer than to come up with it

Yes. They're called "NP Complete" problems.

Improving on the 79% accuracy (2, Funny)

jonaskoelker (922170) | more than 4 years ago | (#30238118)

79% accurate. That's pretty useless. I've got a pair of dice that can do just as badly.

You may be interested in purchasing this chip I have here. It has a very nice fdiv routine. Since we're so good friends, I'll give you a 100.00001353% discount.

Re:79% accuracy ... (0)

Anonymous Coward | more than 4 years ago | (#30238190)

What do you mean "useless". It's already surpassed slashdot.

Re:79% accuracy ... (1)

ShakaUVM (157947) | more than 4 years ago | (#30238490)

>>79% accurate. That's pretty useless. I've got a pair of dice that can do just as badly.

79% accurate? That's good enough for government work!

Re:79% accuracy ... (1)

tolkienfan (892463) | more than 4 years ago | (#30238502)

A factoring algorithm that gives the correct answer with 50% probability (in a short enough time) would be very useful.
Since you can check the answer with a single multiply, you keep trying until you have the correct answer.

This is one of a set of problems labeled "NP" - a characteristic is that you can verify an possible answer in polynomial time.
Any of these problems can be solved with a polynomial time algorithm that gives the correct answer 50% of the time.

Re:79% accuracy ... (2, Informative)

xZgf6xHx2uhoAj9D (1160707) | more than 4 years ago | (#30238768)

Actually quantum computing is, by design, probabilistic. Every specifically quantum algorithm (even Shor's infamous factoring algorithm) gives incorrect results by design for the simple reason that it's really not possible to have quantum algorithms which succeed all the time (unless you forgeo their quantum properties). So long as the probability of a correct answer is strictly greater than 0.5, however, one only has to repeat the computation a constant number of times to get the probability of success arbitrarily close to 1.

correct and incorrect? (1)

bongey (974911) | more than 4 years ago | (#30237818)

So is that 21% of the time is was both correct and incorrect ?

Re:correct and incorrect? (5, Funny)

NoYob (1630681) | more than 4 years ago | (#30237888)

So is that 21% of the time is was both correct and incorrect ?

That's correct and the other 79% of the time the cat died.

Obligatory Anchorman quote (1)

spineboy (22918) | more than 4 years ago | (#30238082)

Loosely paraphrased here
79% of the time it is 100% accurate

Re:correct and incorrect? (2, Funny)

V!NCENT (1105021) | more than 4 years ago | (#30238210)

So in the other universe 21% of the time cats die. I knew this universe was violent!

On the death of cats (1)

jonaskoelker (922170) | more than 4 years ago | (#30239594)

I knew this universe was violent!

Blame god. He goes and kills a kitten every night after he visits me to tuck me in.

Err... I mean... Forget I said anything. Yes, it's violent here. Ahem.

Re:correct and incorrect? (0)

Anonymous Coward | more than 4 years ago | (#30240144)

I don't believe a quantum computer can not operate accurately. However, it can be observed inaccurately! Perhaps they should replace the observer and try again.

Re:correct and incorrect? (1)

Bottles (1672000) | more than 4 years ago | (#30237892)

Well, yes and no.

Re:correct and incorrect? (0)

Anonymous Coward | more than 4 years ago | (#30238104)

Depends if you look at it or not

Re:correct and incorrect? (1)

electricbern (1222632) | more than 4 years ago | (#30238002)

Yes, although there is a 21% chance that my answer is wrong.

Re:correct and incorrect? (1)

daveime (1253762) | more than 4 years ago | (#30238688)

The actual state of the machine is "all possibilities at once", it is the act of observing the result that actually collapses the waveform and causes the answer to settle into a specific state.

So obviously, in the 21% cases, the operator just looked at the computer "in a funny way".

wait (1)

jaggeh (1485669) | more than 4 years ago | (#30237878)

79% of the time they work every time

Think of the cats! (1)

jeffshoaf (611794) | more than 4 years ago | (#30237884)

Were any cats harmed in the running of the programs?

Re:Think of the cats! (1)

V!NCENT (1105021) | more than 4 years ago | (#30238226)

$cat BoxInside.sh ...

Oh crap!

Could be worse... (3, Funny)

Shivinski (1053538) | more than 4 years ago | (#30237898)

On average, the quantum computer operated accurately 79 percent of the time,

Well, its better then anything Microsoft can come up with...I'll take 10!

Re:Could be worse... (0, Flamebait)

DiegoBravo (324012) | more than 4 years ago | (#30238574)

And is better than the probability of total Linux hardware support for any random pc/laptop!

Re:Could be worse... (0)

Anonymous Coward | more than 4 years ago | (#30238676)

You meant windows 7, right? Linux got far better than it in drivers lately...

Accurate only 79% of the time? (1)

Yvan256 (722131) | more than 4 years ago | (#30237952)

Since it's a Quantum Computer, shouldn't reading the results actually mess up the results? Or at least that's what I understood from that Futurama racing joke.

In Some Alternate Universe (5, Funny)

WED Fan (911325) | more than 4 years ago | (#30238030)

In some alternate universe, there's a guy who is riding a bus, a thought pops into his head, "Pick a number between 1 and 100. Now, add 3. Now, divide by 13...". 99% of the time, he does the problem in his head, 79% of the time he finishes it. 1% of the time, he says, "Screw it". 100% of the time, he wonders where the hell these things are coming from and decides to check himself into the nearest mental ward.

Quantum computing is screwing up someone's day.

Re:In Some Alternate Universe (1)

StripedCow (776465) | more than 4 years ago | (#30238436)

And that's by having only one quantum computer in a single universe... now imagine what would happen if all the other universes would start inventing such computers!

Re:In Some Alternate Universe (1)

StripedCow (776465) | more than 4 years ago | (#30238446)

By the way, who would be able to claim the invention when the universes merge? Hmm, intriguing concept, prior art in a parallel universe...

Re:In Some Alternate Universe (1)

WED Fan (911325) | more than 4 years ago | (#30239980)

I've already patented "A Quantum Method for Parralel Copyright, Trademark, and Patent Registration".

(Note: I assert that this comment is now prior art in all Universes and proof of my ownership of said patent, including Universes that contain no processes or concepts of copyright, trademark, or patent.)

Re:In Some Alternate Universe (0)

Anonymous Coward | more than 4 years ago | (#30240078)

By the way, who would be able to claim the invention when the universes merge? Hmm, intriguing concept, prior art in a parallel universe...

Oh, just get the other guy's patent lawyer declared Anathem [wikipedia.org] :)

How do they know? (2, Insightful)

jpmorgan (517966) | more than 4 years ago | (#30238150)

I'm curious how they could possibly know that it operated correctly 79% of the time, since the underlying quantum state isn't observable. You could say it produced the 'correct' results 79% of the time, but that's not the same as saying it operated correctly 79% of the time; it's very possible for a quantum computer to operate incorrectly and still produce the right result, through sheer random chance.

I suppose I could read the paper.

Re:How do they know? (5, Funny)

palegray.net (1195047) | more than 4 years ago | (#30238206)

I suppose I could read the paper.

I think you might be on to something here.

Re:How do they know? (0)

Anonymous Coward | more than 4 years ago | (#30240128)

I suppose I could read the paper.

I think you might be on to something here.

Dude, that kind of speak could undermine the entire slashdot-commenting community.

Re:How do they know? (0)

Anonymous Coward | more than 4 years ago | (#30238580)

It's possible, but I'd bet that the odds of getting the correct answer after a failure are negligible (millions to one?) and so wouldn't significantly alter their claim that it was working correctly 79% of the time.

Re:How do they know? (1)

FarFromUnique (1452027) | more than 4 years ago | (#30238638)

+5 Accurate! If only I had actual mod points...

Ha ha (2, Insightful)

cefek (148764) | more than 4 years ago | (#30238174)

Can you imagine the accuracy of a Beowulf cluster of that?

Re:Ha ha (1)

OricAtmos48K (979353) | more than 4 years ago | (#30238200)

Again 79%. size does not matter

Why is the result Right or Wrong? (1)

WED Fan (911325) | more than 4 years ago | (#30238310)

Or, you get more combinations of right, wrong, and other as answers. Now, what happens when one unit in the cluster suddenly starts throw the right answer 100%?

Or, goes 100% wrong?

Or, goes 100% OTHER?

What if it taps something we cannot comprehend?

What if it hits "other" just once. And as a result, somewhere in the timeless Eternity, God freezes, bends over, and monkeys fly out of His ass?

Re:Ha ha (1, Informative)

Anonymous Coward | more than 4 years ago | (#30238354)

not if they are parallel. computations that are done on each node where the majority of the answer is the right answer (as long as it's accurate past 50%). won't increase speed but will increase accuracy.

Re:Ha ha (3, Funny)

dem0n1 (1170795) | more than 4 years ago | (#30238378)

Again 79%. size does not matter

That's what she sighed as she patted him on the knee and then walked out of his life never to be seen again.

Re:Ha ha (1)

Sulphur (1548251) | more than 4 years ago | (#30238522)

21% of the time Beowulf accidentally shakes Grendel's hand.

Bye-bye encryption? (1)

orkysoft (93727) | more than 4 years ago | (#30238386)

How long until they get it to factor huge numbers?

Re:Bye-bye encryption? (1)

u38cg (607297) | more than 4 years ago | (#30238718)

Conditioning on the NSA? A negative number, I'd suspect.

Bring it on, save the nation (1)

hwyhobo (1420503) | more than 4 years ago | (#30238470)

Experimental physicist Boris Blinov says that one of the most exciting things about the new study is that the quantum computer may be scaled up. “What’s most impressive and important is that they did it in the way that can be applied to a larger-scale system,” says Blinov, of the University of Washington in Seattle. “The very same techniques they’ve used for two qubits can be applied to much larger systems.”

Pretty soon they will be able to calculate the US budget with accuracy heretofore unmatched by any recent administration.

Re:Bring it on, save the nation (1)

daveime (1253762) | more than 4 years ago | (#30238716)

You don't need two quantum states for that, one will suffice.

In The Red, until the end of the universe (where I hear there's a very nice restaurant).

Re:Bring it on, save the nation (1)

hwyhobo (1420503) | more than 4 years ago | (#30239974)

You don't need two quantum states for that, one will suffice.

Funny +1

In The Red, until the end of the universe

Insightful +1

Too bad I cannot moderate in the same thread I post in.

Make more and check correlation (0)

Anonymous Coward | more than 4 years ago | (#30238512)

Put them all in a cold vacuum chamber and check whether there is any correlation in errors. Maybe you could detect some wobbles in space time.

First infinite loop.... (4, Funny)

Temujin_12 (832986) | more than 4 years ago | (#30238608)

do {
    solveProblem();
} until (getPhotonPosition() && getPhotonVelocity());

Re:First infinite loop.... (0)

Anonymous Coward | more than 4 years ago | (#30239314)

Something tells me that it might know the photon's velocity...

Ahh... (1)

Cytlid (95255) | more than 4 years ago | (#30238780)

The old 80-20 rule. The other 21% of failures caused the first 79% to be correct.

Well (1)

mewsenews (251487) | more than 4 years ago | (#30238830)

You know what they say... 79% of the time, it's correct every time.

Who cares? (1)

drej (1663541) | more than 4 years ago | (#30238946)

That's all well and good, but the important thing is: Will it be able to run Crysis 2?

the 21% it was also correct (0)

Anonymous Coward | more than 4 years ago | (#30239036)

but on a different quantum space, of course.

79% is the best you can expect in the Slow Zone. (1)

jeffb (2.718) (1189693) | more than 4 years ago | (#30239134)

Get out into the Beyond [wikipedia.org] , and you can reasonably expect 100% efficiency out of your quantum computers. Keep going into the Transcend, and you can reasonably expect better than 100% efficiency -- or at least that's what it looks like to merely-human minds.

Just don't open any unsigned JAR files.

Yeah, but... (1)

Seriousity (1441391) | more than 4 years ago | (#30239332)

Can it run Linux?

Re:Yeah, but... (1)

md65536 (670240) | more than 4 years ago | (#30239840)

I think a machine like that is better suited for Windows, because it can offer an improvement. Users found that it would only crash reliably about 79% as often as expected.

Anonymous Coward (0)

Anonymous Coward | more than 4 years ago | (#30240684)

79 per cent of the time it works every time

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