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A "Photon Machine Gun" For Quantum Computers
An anonymous reader writes "Generating entangled photons in a reliable way is impossible right now, stalling the development of the optical quantum computers that would use entangled photons as quantum bits (qubits). Because entangled photons can only be produced at random — which takes time — the most powerful optical quantum computing device use only 6 qubits. UK and Israeli quantum physicists have designed a blueprint for a 'quantum machine gun' that fires out barrages of entangled photons on demand. They think within a few years this device will be built, and could lead to quantum computing using 20 to 30 qubits. Every additional qubit doubles the computing power, so these quantum computers could outperform any existing classical computer, the researchers say. The quantum machine gun is described as 'one of the most exciting theoretical proposals I've read in five years' by a leading quantum physicist." The research was published in Physical Review Letters earlier this month.
Every additional qubit doubles the computing power, so these quantum computers could outperform any existing classical computer, the researchers say.
But only for probabilistic algorithms. It's not going to be faster at everything.
Every additional qubit doubles the computing power, so these quantum computers could outperform any existing classical computer, the researchers say.
I thought that the "power doubling" was not in a traditional sense.. the qubit is fantastic at pattern matching and search functions, but no better than a classical computer for something like, say, a video game requiring finite mathematical calculations. I'd state this as a fact, because I've read this in at least a couple places, but seeing as how quantum physicists haunt this forum, I can't say I know as well as them. But this power is only useful in very specific circumstances, AFAIK.
If you can read this... 01110101 01110010 00100000 01100001 00100000 01100111 01100101 01100101 01101011
Israeli quantum physicists have designed a blueprint for a 'quantum machine gun'
In other news, Palestinian quantum physicists have designed shoulder-mounted quantum launchers and quantum vests in response.
Civilians are hopeful for peace and terrified for escalation of hostilities.
I thought that the "power doubling" was not in a traditional sense.. the qubit is fantastic at pattern matching and search functions
Which is all that really matters for breaking encryption, and is the whole reason we have computers in the first place.
So my question is how many bits of encryption do I need to keep a 20~30 qbit computer out of my truecrypt partition?
[Fuck Beta]
o0t!
Again, Trek predicts the future.
Table-ized A.I.
On the other hand, some problems like collision testing are really just pattern matching or search functions, and that has a huge amount of applicability to game design. There are many other similar problems that, at first blush, sound easy, but turn out to be quite difficult, and I've yet to see a modern game with physics that doesn't somehow manage to get objects stuck in floors or falling through levels.
It's going to be faster at everything.
Certainly, the Europeans dominate the winners of Noble Prizes in science.
Germans invented the jet aircraft, the guided missile, the computer, calculus, etc. The English invented calculus. The French developed the metric system. Also, the Japanese have done quite well. They invented the blue light-emitting diode, hybrid engines for cars, process technologies for cost effectively producing large LCD screens, etc.
The one group that is missing from this arena of technical accomplishments is Africans and African-Americans. Why are they absent?
We know that African IQ is small than Japanese/European IQ by about 20 points. Can this large difference in IQ explain the gross failure of all societies dominated by Africans?
Even for traditional computers, adding 1 bit of memory doubles the size of problems you can tackle with a log-space algorithm. There's nothing magic about it.
That when this technology is finally put to practical use, i.e. home computers, the cost of hardware is going to go up? Isn't there an implied health risk involving high speed protons, such as in the form of radiation? Granted, it would be on a very weak level, alpha particles, but consistent exposure to said particles over time would have an impact on ones health. I suppose that could be stopped by the case though... Just a thought.
"Chance favors only the prepared mind." -Archimedes
imagine a Beowulf cluster of... NO! NONONO!
Operation Guillotine is in effect.
say hello to my little friend... (Please try to keep minds out of the gutter if possible)
Deja Moo: The feeling you've heard this bullsh*t before.
With what I can tell... 256 or 512 should keep you safe from that.
Ok, so on this site bursting with intelligent, educated folk, the following question(s) might make me look like a village idiot, but what the hell. It's damn interesting stuff and I want to know!
Exactly how does quantum computing work? I have a fleeting grip the basic stuff; qubits existing with states 0, 1 and "superposition" (i.e. all possible states) and that by actively measuring it's state (sending a photon or whatever bumping into it) you collapse it, and it's entangled mate, into a "classical state". If I place a shot glass in a dark room and tell you it could be empty, full or anything in between but the only way for you to find out is to A) Take the shot, or B) dump another 4cc of Tequila into the glass and see if it spills over, is the shot glass a cubit? To you, it is in a "superstate" until you actively measure it, an act that in itself makes the glass full or empty.
How does this equate to computing? I might just have spent too much time with Proteus fiddling about with gates and stuff trying to make a very basic functional computing device, but isn't some sort of computing device needed to compute something? Even with Quantum Gates, 30 qubits seem like a very insignificant amount of building blocks to compute anything..
Lastly, how would/will qubits be used to revolutionize storage? I get the allure of storing bits on a subatomic level but if the whole hype is about storage density, it sort of kills the magic for me.
It's called a "Strobe Light", stupid.
I know.....bad joke.....
Knowing Google's lust for data collection, the Soviet Union is still alive and well inside the psyche of Sergey Brin....
Alright, here's how it works: A quantum computer can efficiently execute algorithms the class BQP, which means "Bounded error, quantum, polynomial time". Since all quantum algorithms are probabilistic, "bounded error" means just that - that you can, basically speaking, run the algorithm as many times as you want to get the error as low as you want. Polynomial time means the time you have to wait increases relatively slowly with respect to the size of the input[1].
What the previous comments seem to be talking about here is either EXPTIME (things that take exponential time, period, like solving chess when the input to the problem is the size of the board), or NP (puzzles where, if someone gives you a potential solution, you can check whether it's right rather quickly). Let's be clear, ahead of all: BQP is not EXPTIME. Whether BQP contains NP is an unsolved question, but so is whether P == NP (that is, whether you can use an ordinary computer to solve puzzles where you can recognize a solution quickly, for any sort of such puzzle).
The short of it is: for some algorithms, like Shor's algorithm (which cracks certain types of public key cryptography), there will be an exponential speedup. Quantum computers can break RSA. However, this does not mean that quantum computers will be of much help in breaking AES[2]. Some public key algorithms may also be resistant to cracking by quantum computers - the Lamport signature definitely is (but can be only used once, or a finite number of times in a tree configuration), while other candidates without this finite-use limit include McEliece and NTRU.
[1] Yes, I know about how 1.0001^n is, in practice, efficient, while n^10000 is not, but you'll rarely happen upon such algorithms.
[2] Grover's algorithm means you have to double the number of bits in your key to get the same security given the same power, but I find it very unlikely that we're going to see quantum computers as fast as the quickest deterministic code cracking machines (no quantum Deep Crack yet), so this most likely isn't a threat.
If you are very unfortunate, n qubits can map 2^n -1 bits. -1 because 2^0 = 1, and that'd just be weird.
If this is the case, then a 6 qubit machine maps 63 bits, but 20 would map 1,048,575 bits (1 Mbit of information) and 30 would map 1 Gbit of information.
That doesn't sound right to me. Do you have a citation? Or did you just make that up?
Yeah, seems wrong to me too. I bet he's wrong.
the whole thing about quantum computers is that they should be able to factor numbers extremely fast, so no matter how many bits of encryption you choose, you'll still be screwed.
I've heard that there are now new encryption algorithms which should be able to withstand quantum computers. I don't know anything about them, so maybe someone else could explain.
Say flashlight.
Random
Traditional computer's performance doubles too, so we don't care!
Correctly implemented symmetric encryption with 512 to 1024 bit keys should remain safe for some time. Public key encryption will be broken entirely, regardless of the key size because decryption without key will not be significantly enough slower than encryption with key.
The Moslems!
Loud and arrogant and self-righteous and completely void of all logical ability, and... did I mention loud?
I know what you're thinking: "Did he flip six qbits or only five?" Well, to tell you the truth, in all this excitement I kind of lost track myself. But being as this is a Photon Machine Gun, the most powerful quantum entanglement source in the world, and would blow your head clean off, you've got to ask yourself one question: Is the cat dead or alive ? Well, is it, punk ?
Squirrel!
Uh, how many states can no bits exist in? I would've said 1, myself.
For how long?
Build a Man a Fire, and He'll Be Warm for a Day. Set a Man on Fire, and He'll Be Warm for the Rest of His Life.
Uh, how many states can no bits exist in? I would've said 1, myself.
Return type void is always the same.
Why is this modded troll? The poster has stated a legitimate argument and I'd mod him up if I could but I'm on a public computer and can't remember my password.
The quantum machine gun is described as 'one of the most exciting theoretical proposals I've read in five years' by a leading quantum physicist.
The long winter nights must just fly by.
Finally had enough. Come see us over at https://soylentnews.org/
The quantum algorithm for factoring does not just divide repeatedly "in parallel." Shor's algorithm really describes a specially built machine for factoring (which converts factoring to period finding, and a fourier analysis is forced and sampled).
In fact, I first studied Shor's algorithm in order to understand why good programmers weren't looking at it, generalizing it, and writing a million more algorithms. I was disappointed to learn that we are not far enough along to describe a universal quantum computer and are still in the mode of building special-purpose machines. Like the early bomb dropping "computers" of WW2, results are still being generated but without a concept of universality.
We don't have the math for universal quantum computation since it is still unknown what they are capable of (what their universe consists of). Until the math arrives, we're stuck with this scatter-shot approach.
I honestly haven't a clue. I just figured that 2^n would give you an exponential power gain to the point where 20-30 qubits would be enough to brute force most types of encryptions.
If you have a device that can brute force a 1 Mbit to 1 Gbit key in a single step, your regular encryption types are dead.
But I haven't a clue how it maps from qubit to bit. The maths shown on the Wiki page and on quantum computer is way above my head. The last one notes: "For example, a 300-qubit quantum computer has a state described by 2^300 (approximately 10^90) complex numbers, more than the number of atoms in the observable universe."
But - no clue. I wasn't aiming for informative, I was hoping for interesting (as in, that's an interesting thought, let's see what the experts say).
So... Is "photon machine gun" another would for a light bulb?
why not just factor encryption keys in like base 7 or something? All the keys I've heard discussed so far seem to be base 2 based...
"Freedom in the USA is not the ability to do what you want. It is the ability to stop others from doing what THEY want"
cp /dev/random ~/unencryptableMessage.txt
On a serious note, I haven't heard of such algorithms. Are Quantum computers good with cracking all encryptions, or just many of the methods used for such?
I read TFA and all I got was this lousy cookie
...And maybe a few years after that we'll have 32-qubit machines, so we can start factoring unsigned ints.
For now, we're just going to stick to factoring 15 though.
I checked the patent in your link. It was re-examined in 2003, and all claims canceled. Whew, my kids are safe.
"Uh... yeah, Brain, but where are we going to find rubber pants our size?" --Pinky
Even if you were right, I'm sure there's plenty of searching and pattern matching in video games. Especially searching.
Regardless, video games are not nearly as interesting an encryption.
Then you're getting into 'security through obscurity' -- you're secure as long as nobody knows what weird algorithm you're using to encrypt your data. That's not real security. One leak and everything you've ever encrypted is plain text.
Entanglement is described as 'spooky action at a distance'. What if the entangled particles are actually close to each other in a higher or lower dimension? In that case they could be arbitrarily far from each other in our dimension, while still being tightly wound in the other dimension. All the problems faced with regards to consistency of production and "random" disentanglement are therefore a result of not being able to see into and track movements in this higher or lower dimension.
Hence, for example, in the case of entangled electrons, both of them might be in the same spot in the other dimension while they move in ours. As long as they stick together they might also be required to have opposite values for their properties. In that case, measuring one would cause a change in spin of the other. When they stop sticking together, that no longer applies.
I vote for 2D universe with holographic interface.
I wonder if this is inherent in the universe representing some absolute barrier to doing Quantum Entanglement computations, 'Yes the universe will do your computation instantly, but not until you provide umpteen zillion entangled qbits. The universe will take 10^100 years to aquire sufficient randomness, please use /dev/urandom for quicker testing.
...
3.999794!
A prime number is prime in any base. You can't gain any complexity by using another base like you suggest.
Now where am I going to find a quantum Bikini Girl to fire my quantum machine gun?
IA Quantum Uzi's for sale, free with a new car.....
I would like to know because if it gets tied into the main deflector array it could cause a metreon cascade in the warp core's plasma injectors.
Tsukasa: All I really want, is to be left alone...
but no better than a classical computer for something like, say, a video game requiring finite mathematical calculations.
What about Q-Bert?
And as an additional note, for every ten afterward, you would multiply by roughly a thousand. I.E.
2^10 = 1,024 b = 1kb
2^20 = 1,048,576 b = 1mb
2^30 = 1,073,741,824 b = 1gb
2^40 = 1,099,511,627,776 b = 1tb
I suspect this is nothing new to you, but, there are other people who might find it helpful to know.
How good would quantum computers be for raytracing (particularly of the hard-core globally illuminated variety) ?
Why OpalCalc is the best Windows calc
That is wrong.
That is all.
Pattern matching and searching power will come in very handy for the task of creating a stronger Go-playing computer program. The "exploding" size of the search tree in Go is just too much for classical computer systems. If that tree could be trimmed with an intelligent pattern matching routine, solving Go could finally take less time than what the universe has existed. http://en.wikipedia.org/wiki/Computer_Go
$ q_dec ~/unencryptableMessage.txt
0011100
0100010
1000001
1000001
1000001
0100010
0011100
`echo $[0x853204FA81]|tr 0-9 ionbsdeaml`@gmail.com
Infinity qubits would be needed if you one time pad your information (essentially doubling the disk space required to encrypt of course).
Disclaimer: I am not god.
We may not be created equal
But we can be treated equal.