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Will Quantum Computing Make It Out of the Lab?
alphadogg writes "Researchers have been working on quantum systems for more than a decade, in the hopes of developing super-tiny, super-powerful computers. And while there is still plenty of excitement surrounding quantum computing, significant roadblocks are causing some to question whether quantum computing will ever make it out of the lab. 'Artur Ekert, professor of Quantum Physics, Mathematical Institute at the University of Oxford, says physicists today can only control a handful of quantum bits, which is adequate for quantum communication and quantum cryptography, but nothing more. He notes that it will take a few more domesticated qubits to produce quantum repeaters and quantum memories, and even more to protect and correct quantum data. "Add still a few more qubits, and we should be able to run quantum simulations of some quantum phenomena and so forth. But when this process arrives to 'a practical quantum computer' is very much a question of defining what 'a practical quantum computer' really is. The best outcome of our research in this field would be to discover that we cannot build a quantum computer for some very fundamental reason, then maybe we would learn something new and something profound about the laws of nature," Ekert says.'"
*Shakes the magic 8-electron*
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With just a few more qubits, I could have entangled first post.
Once some lab figures out how to do it it will seem so easy in hindsight.
To offset political mods, replace Flamebait with Insightful.
Quantum Computing isn't going to work immediately, it's just life. It's going to make small progressions over time. Eventually there will be advancements that will make them practical for a given purpose. They will follow something like a "Moore's Law" of Quantum computing. Then some intelligent person will utter "I think there is a world market for maybe five Quantum computers"!!!
The current state of the field is advancing. The real problem as discussed in TFA is scaling quantum computers in a useful way that can still do error correction. Shore's algorithm which allows you to quickly factor numbers using a quantum computer requires on the order of n qbits to factor an n bit number. So if one wants to factor say a 300 digit number used in some public key crypto system you would need to control around 300 qbits. The technology for that is clearly very far. There's been recent work using superconducting systems and using quantum dots for qbits both of which look more promising than previous systems. (The first experiments were done with NMR systems which are clearly not very scalable).
From a strictly theoretical compsci perspective, the set of things it seems that quantum computers can do seems to be growing larger. Recent work by Scott Aaronson and others suggest that BQP (the set of problems which can be easily solved by a quantum computer with a low probability of error) may not lie in the polynomial hierarchy at all. http://arxiv.org/abs/0910.4698. This is a much stronger claim then the claim that BQP doesn't lie in NP. This raises the hope that there may be some problems thought of as extremely difficult that lie in NP. However, trying to actually prove any strong results at this point is likely going to be really tough. At this point although many suspect that BPP (the classical analog of BQP) is equal to P, at this point we can't even prove that BPP lies in NP. In many ways theoretical comp sci is still very much in its infancy.
Maybe; maybe not.
Welcome to the Panopticon. Used to be a prison, now it's your home.
When high frequency trading finds a way to use this to make more money, you better believe they will make it work.
That'll be fun. You won't even know whether you own a stock until you open the box and look.
1) We have built qbits
2) We have entangled qbits
3) We have implemented the CNOT which is the universal gate for quantum computing (similar to NAND/NOR universal gates in classical computing)
The question is scaling up number of qbits, increasing coherence times (and possibly using coding solutions to reduce decoherence problems).
We have a number of quantum algorithms waiting to be implemented, and even have quantum programming languages that you can run simulations on at home today. And there is even a LinkedIn Group on quantum information science.
But I must admit that it could end up like fusion. We have all the basic theoretical knowledge of how to do fusion, and we can do a bit of fusion in the lab, what we lack is the engineering knowledge to achieve enough fusion on a large enough scale to make it practical.
The answer is both Yes and No.
It is a superposition of skates.
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Apple: partner with no one, sue everyone.
I'll see your senator, and I'll raise you two judges.
the history of the PC. How many decades did it take for us to get where we are? The first PC was some 50 years in the making and by today's standards was downright laughable in its capabilities. The first computers weren't Von Neumann machines either. You had to have a team of dedicated operators reconfigure patch cables between between outputs and inputs for each an every calculation! To be so pessimistic so early in the life of quantum computing is insulting to the progress we've made so far which is considerably outstripping the pace of development of the modern computer.
Two of my imaginary friends reproduced once
Maybe they could arrange with their pals in the stock exchange to entangle things so that no matter what happens, they win :).
Depends on the flavor of cat.
It is not so much of "will it" as opposed to "when will it." And to what degree of success & usefulness. I'll give the timeline roughly around the same time as fusion.
Vote monkeys into Congress. They are cheaper and more trustworthy.
We're talking internet right here. The problem faced with long-distance quantum stuff is that the bigger the lenght of the channel, the higher the probability of error.
So how do you implement this? You make a shitload of entangled particle pairs in such a way that it works like an error-correction-protocol (computers, hmkey? They proces, duh) and then send the result by means of more entagled particle pairs to the next repeater, or until the package has reached its destination.
You could have Googled that, you know...
Here be signatures
Two qubits should be enough for anyone.
Oh c'mon, somebody had to say it. Might as well save some budding tech CEO from being cursed with that quote for all time.
Returned Peace Corps IT Volunteer
Didn't all of these things take 30+ years to develop?
Lockheed-Martin already bought one. It's made by D-Wave Systems and is called the D-Wave One. It is known as the first commercial quantum super computer. It has 128 qbits and has been out for about a year already.
source?
schizophrenia
It has to be able to run Doom. And Barney Doom.
And, obviously, Linux. OpenBSD would be the Big Win.
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While I'm highly skeptical about building a useful general-purpose quantum computer, I think that there may be great value in incorporating that tech into traditional computers. In other words, a four-qubit computer may be nearly useless except for very specific problems; but if it was part of your desktop computer, it would give it a large boost in all sorts of power.
For instance, encryption is highly related to compression. I believe that a quantum computer would be highly efficient at compressing and decompressing data... which is a task CPUs (and GPUs) do a lot.
can it run crisis 2 at full speed with at least 60fps at full detail?
Quantum computing was dying, or it wasn't. Then Netcraft confirmed it and collapsed the state to dead.
I imagine quantum computers will be possible, but only after a fundamental change in how we think about and design things. Sort of like how future technology was imagined in the 30's and 40's. It took the invention of the transistor and other solid state devices to get people to re-think how things could be designed.
Proverbs 21:19
No.
* Carthago Delenda Est *
that's not a quantum system... that's what the internet is now.
No shit, Sherlock. But it's not quantum based. How else do you want to make a fully working quantum computer, if you can't have a quantum based network 'card'?
PS: Google starting English sentences with capitals...
Here be signatures
Yep, I remember that, like yesterday. The catch-phrase was something like "To big to fail".
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
The quantum summary quantumly mentions many quantum uses of the word quantum.
And for some filler, maybe they'll make a quantum grill to quantum barbecue quantum burgers and quantum hot dogs.
William of Ockham had no beard. The most likely explanation is that it was chewed off by squirrels every morning.
Uh. Don't feed the trolls. This guy is one of the more obvious ones.
which is totally what she said
And the world STILL sucks. We do not live under an uber-American world totality where we all sing the National Anthem at breakfast and those of the wrong skin color, temperament, or with irritable bowel syndrome have been quietly taken out back and shot.
Fat lot of good that super-secret quantum supercomputer in the hands of a secretive US government agency did
Here's to hot beer, cold women, and Glaswegian kisses for all.
We struggle to keep quantum computer IN lab!
This sig is not paradoxical or ironic.
You can't build a quantum computer here because we're a simulation already running in another quantum computer and there isn't enough resolution in the simulation's space time manifold to support the necessary function of another quantum computer. Duh!
All theoretical physicists should be hung by the chalk covered thumbs. Shouldn't we maybe......oh I don't know......INVENT SOMETHING!!!!!!!! What happened to all the scientists that actually experimented with real world problems and solutions that are within our grasp rather than take a hit of acid and calculate PI to a million digits. Especially seeing as how most of the field is based on the great moron's (einstein) postulate that NOTHING can travel faster than light. IT WAS A THEORY!!!!! STOP INVENTING FACTS BASED ON INVENTED FACTS AND INVENT A FREAKING TOASTER THAT DOESN'T BURN MY MUFFINS!!!! AND BTW, STOP TEACHING YOUR BULLSHIT THEORIES AS IF THEY WERE PROVEN FACTS. IT STIFLES FREE THINKING AND INNOVATION. Sorry for that but these chalkboard surfing morons have spent the last 50-75 years speculating on the speculation of the speculation of the speculation of.... I understand that you have to start somewhere but there comes a time when you have to start proving or disproving your theories and move on to the next, you can watch your Star Trek reruns tomorrow. The planet is running out of juice, literally, and we need real scientists to solve very real problems. A bunch of bouncing balls on a canvas is not a parallel universe IT"S A BUNCH OF BALLS ON A CANVAS YOU MORONS! I know this was about Quantum computing, but somebody mentioned physicists and they just piss me off
-- L8R, guitardood
I thought this was about quantum computing not quantum thinking.
-- L8R, guitardood
I, for one, am putting my bets on neutrino computing.
Using neutrinos faster than the speed of light, it will be possible to send messages back in time, thereby enabling any kind of brute force algorithm. Just do a brute force search, and instantly receive a message from the future containing the answer to your problem.
If Pandora's box is destined to be opened, *I* want to be the one to open it.
Because of the impact of Q.C. on crypto systems, I think it unlikely that the announcement will rapidly follow a real practical breakthrough development. Unless there is a very strong willed stinker on the development team, who can resist the bribes and threats, the policy is going to be to keep it under wraps as long as possible. The news will throw the financial community into a panic as no electronic encryption or signature systems will be considered reliable. There is too much money at risk for a product announcement to come out within years of the development.
Not to mention that the spies of the world would all love to be the only ones with the technology. Let the bad guys on the other side think that their kilo-bit keys are secure so they keep using them. Enigma was the biggest secret of WW2, and mad a real difference to winning the war. Had the Germans known their codes were insecure we might be karate chopping birds for salutes today.
With the threats and bribes available, it is a secret that can be kept a long time.
BTW, if there is a reason it isn't feasible, that would be almost as big a secret. Just slightly different motives.
Paranoia
Well, the problem with the NSA's super-secret quantum computer is that they can't tell other agencies the result of decrypting any message unless they can think of some plausible way of decrypting it without needing a quantum computer. If they did, the world would know that they had a quantum computer and that RSA and related algorithms were totally compromised, and they'd switch to using something else.
Well, maybe not, but the same situation did occur in the second world war - Churchill didn't allow civilians to be warned of German bombing raids, because doing so would have let the Germans know that Enigma was broken.
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There has been an exponential increase in the number of qubits under control since the first serious experiments started almost two decades ago. If the current trend continues, we will have usable quantum computers between 2020 and 2023.
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Yes. it will. the time frame for QC leaving the lab is something from 15 years to 50years. If it doesn't work in the next 50years it means we understand something about quantum mechanics significantly wrong (or we figured QC is useless for some reason).
There are several milestones:
1) implementing single qubits (done in many systems) and high fidelity readout (done on a few systems)
2) high fidelity operations on single qubits (done on some systems)
3) controllable coupling of qubits (done on some systems) witn good on-off ratio (done on a few systems) in a decent architecture (only very few experiments AFAIU) with a demonstration of simple QIP algorithms (done)
4) scalability in the production yield for solid state systems (NOT done, by far not) or in the resource usage for other systems (atom chips are promising)
5) Quantum media conversion between solid state and optics (done) with decent fidelity (far, far away) for using QIP in Quantum communication as local processors
6) Error correcting schemes to lower the threshold for 2) to a doable value for building a scalable computer (that is, a computer which gains computational power when ressources are added): theroretical (done) and experimental (far away)
7) Theoretical understanding of QIP Architecture (not done)
6, which implies 1-4 (and depending on the scheme also 5) have been solved is the criterion for building an arbitrary powerful QC for arbitrary money. The more you exceed the absolute thresholds imposed onto 2) and 4) the more power you will gain by adding resources (it could be 10 or 10000 physical qubits needed for 1 logical qubit). The question is: when will it be economical to build it? I cant answer this, but the first thing where it may pay off is for protein folding simulations. We are looking at replacing a 100MW input power classical computer by a some MW input power quantum computer (condensing helium). We may look at power cost savings of 10 to 100million of dollars per year runtime of the QC. Currently the schemes which are predicted to scale with current HW (on the rather optimistic end, i.e. the best experiments ever done) may require roughly a 100Million - 1billion Dollar investment into Hardware alone per QC (hand waving approximation), obviously unacceptable. However if the price goes down by a facto of 10 to 100 (which could happen in the next 20 years if better material or schemes are found), then it would be economical.
"Will Quantum Computing Make It Out of the Lab?" Is an interesting but isn't asking it result in changing the outcome?
...steampunk a quantum pyewta?
Does anyone remember the Quantum hard drive company? What was in them hard drives?
I'll try to answer this, even though it's a little late, and I don't know if you'll ever read this. Be warned that I'm not a physicist -- but I've studied quite a bit of quantum computing, and I asked the same kinds of questions you're asking.
The thing is, a superposition of 2 states (or actually any finite number of states) is not really that interesting or weird, unless you're also talking about entanglement. Unfortunately, quantum computers really need entanglement to work. [Note that when you're talking about position, momentum, energy or time (and many other things), the number of states is infinite, so things become even weirder.]
The way to measure an electron spin (I'll stick to this example) is to apply around the electron a strong magnetic field in the "up" direction (whatever you decide that to be) and wait a little. The amount of time you have to wait depends on the strength of the field you applied -- the stronger the field, the less time you have to wait. If the spin of the electron is already "up", nothing will happen. If the spin of the electron is "down", the electron will emit a photon and its spin will change to "up". This means that if you detect a photon after you applied the magnetic field, you "measured" the spin to be "down", and if there was no photon, you "measured" it to be "up". After the measurement, the original spin is ruined: it's always up, because the magnetic field forces it to become that way.
A superposition of "50%up and 50%down" with no entanglement with anything else can be encoded as an electron with spin pointing to the "left" (or any direction perpendicular to the up/down axis, really). To read it, you would apply the same strong magnetic field pointing up and wait for the photon. You get the same thing as the non-superposition states: a photon means you measured "down", no photon means "up". You can only know the probability (in this case "up" and "down" are both 50%) if you repeat the whole thing from the start (i.e., make the spin point left, and then apply the field and wait for the photon) many times. You can change the amounts in the superposition by varying the angle between the spin and the "up" direction. That is: if the spin is almost, but not quite, in the "up" direction, you would get, say, "95%up and 5%down", and so on.
The problem is: if someone hands you an electron and doesn't tell you which direction its spin is pointing, there's really nothing better you can do to find the direction of the spin than what I described: the best you can get is an "up"/"down" answer relative to a direction of your choosing. Now, the important thing is: when you're talking about an electron that is not entangled, the spin is always pointing in a determinate direction, even though you might not know what it is. That means that there's always a measurement you could make (if you knew which direction to measure) that would give a deterministic answer. That is, if you apply the magnetic field in the direction the electron spin is already pointing, you will always read "up", i.e., no photon.
Things start to become weird when you allow the spins of two (or more) electrons to interact (and become entangled). If you put two electrons close to each other and far from anything else (and free from any magnetic field), after a while their spins will become "maximally entangled", which is a weird state in which the nice property I described above (having a determinate spin direction) is no longer true. That is, there's no direction that you could make a measurement that would give a deterministic answer. For any direction, you'd have 50% of probability of reading up and 50% of down. That remains true even if you separate the electrons, until you (or something else) measures the spin and forces it to be determinate again. You have to note that to measure a spin, any magnetic field is sufficient (although a very weak field would take a relatively long time to measure it), so it's very hard to maintain this entangled state. What i
I don't believe it will. Quantum bits just don't scale as well as normal bits, because they must be entangled. That's the problem.
If I have a working n (normal) bits, it's quite easy to make 2*n bits (just produce the same thing twice and add some circuitry). But with quantum bits, if you have n qubits working, even n+1 qubits is an engineering challenge and 2*n qubits is a major research effort.
And because it scales so badly, it won't become practical. So, your quantum computer broke the crypto on 300 bits? No problem - we just double the number on conventional computer (which is easy) and you're screwed.