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New Idea Could Lead to Quantum RAM
KentuckyFC writes to tell us that scientists in Italy and the US have designed a new method of retrieving information from quantum memory that could allow them to create "Quantum RAM". "Giovannetti's idea is to send the address down the branching tree of connections in such a way that it only affects one switch at a time. The first address qubit sets a switch at the first branching point to go one way or the other; the second qubit is sent that way and sets the switch at the next branching point, and so on. The total number of entangled quantum systems is smaller, and they are not so susceptible to interference, allowing information to be retrieved from memory intact."
atomic-scale memory would create huge waves.
It also could help out on the heat issues as well.
I mean, think about how many atoms are in a normal piece of memory.... yeouch that's a lot of RAM!
Karma Whoring for Fun and Profit.
could this be used to implement extremely efficient binary trees? the structure sounds ideal to be but im hardly an expert.
Well, it's got the word quantum in it, so it's gotta be good... right?
What are the odds that we see this in the next 15 years? 20?
I am not an expert. If I am misled in something, please correct me.
Talk about it if you must, but DO something else instead.
It is all so irrelevant and immaterial as to be immprobable to matter to anyone but you.
Here- I'll just clear all these out of the way:
In Soviet Russia, do our Quantum Ram overlords welcome me, for one, while running a beowulf cluster of linux boxes?
Okay, now we can carry on with the real discussion. Those that feel that all such "obligatory" comments must be made on *every* article can rest appeased, while the rest of us carry on with the real discussion.
[Guy 1] Hey, I had porn loaded into memory
[Guy 2] You changed it by looking at it!
I know I don't really^H^H^H^H^H understand quantum computer, but don't their output rely on some random effects to quickly generate statistics that would take ages with regular brute force computing? So would a quantum RAM provide the stored value only X% of the time?
How else will be I be able to add it to my gaming rig. Do you think this memory has lights on it? I hope so, and that'd look great through my case's side-windows.
Nothing in this really sounds like a new idea except that using this method would have some benefit on the quantum level. It's just a balanced binary decision tree implemented as a (quantum, in this case) circuit such that leaf nodes are stored data and addresses are qbit streams. Am I missing something?
Worse is time incoherency or noise that malforms the data long transit. Imagine the as8k lskcc; fifif88*&&2/213k djc
---- Teach Peace. It's Cheaper Than War.
I don't understand quantum computing..
Unfortunately, with Quantum Leap RAM, the contents are impaired with random bits erased, in a swiss cheese fashion.
Part of the hardcore faithful who believed in Apple long before it was cool again to do so
The last thing I need when attempting to invade my enemies' nano-castles is to have the ram start exhibiting quantum effects and tunneling through the gates!
I mean, isn't every existing quantum computing process a simulation of what might happen if we could actually build something?
Or, to put it another way, isn't quantum computing a mix of wild theories, vaporware, simulation, and experiments that are years away from any marketable product?
It's an honest question, I've never seen any real physical quantum computers and nobody I know has ever seen one either. I am skeptical, but ready to be enlightened if anybody's got some real-world quantum computers out there that can (for example) run a simple 12-million item sort routine.
...3D Realms has announced that Duke Nukem Forever will require installation of quantum RAM.
Proud member of the Weirdo-American community.
Oh boy!
that scientists in Italy have had the idea and a scientist in the US has commented on it?
That's what it looks like from TFA. Of course, it could just be the usual requirement to mention the US because, as we all know, nothing technical happens unless the US has done it.
Quantum computers are a real possibility. They just cease to exist if you try to observe them.
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
I'll bet quantum computers are listed on http://snopes.com/!
Like nanotech, QC still has many high theoretical and practical hurdles before the very first Nanite or quantum gate makes it to market. Lots of wild theorizing, but darn little actual hardware.
In particular, a quantum gate or quantum computer is only capable of probabilistic answers. That is, each gate only has a slight predisposition to give the right answer. How you'd use unreliable gates to do say a 32-bit address decode is a bit of a brain-teaser. Without huge amounts of error-detection and correction, there's only a 1 in 2^32 chance it will access the right memory cell. We need like 1 error in 10^10, a 10^19 shortfall in reliability. I'm loath to slough off nineteen orders of magnitude.
I wonder what it would take to get these things study enough for use, One bump could send your quantum bit for a visit with its neighbor.
Oh BTW, the lights will be way to small to see...
does that mean that the memory contains everything possible at the same time?
Get over it, and just accept it already.
Yes. Quantum computers simply don't exist right now. The theory is arguably around 8 years old. Also, quantum ram at this point would serve almost no purpose, as quantum computing at the cpu level is all that really matters. To others who asked about the efficiency of searching a binary tree, this ram idea would not speed it up in the least. The algorithm for the binary search would be on a square root of two faster in the CPU, but nothing in memroy would really effect it. We're relying on the cancelation of superpositions to get these better algorithms, memory isn't going to change anything. I don't see why so many people are jumping on this bandwagon. Quantum computing is very limited in what it can improve. It's not the end all to solving infinite problems, and contrary to popular belief, its not even going to produce smaller computers with better heat spreading. I mean, seriously, go look at a real research paper on quantum computing and quit listening to what all the reporters are saying. Everyone knows reporters aren't scientists. And before someone says D-Corp (or whatever the name is, I can't remember right now) has claimed to have a commercial quantum computer, remember that they still haven't shown any proof whatsoever, and haven't even released research showing how they have gotten around some of the inherent deadends of quantum computing.
Or at least you will not know whether your program has crashed until it dumps core?
This physicist sounds like he should start a dot.com company!
Whats next? Quantum Hard Drives?
What? Yes, they exist, so far not with much memory though. One was used in '04 to implement Shor's Algorithm to factor the integer 15 (or 2^4-1). I know, baby steps, but sometimes I forget the factors of 15 :-/
Apology to Ubuntu forum.
Small (4-5 bit) quantum computers have been built and experiments have been performed with them.
A theorem of quantum mechanics is that you can't perfectly copy a quantum state as that would allow you to measure the energy of one copy and the time of the other, thus violating the uncertainty principle. In practise what happens is that the two systems become entangled so that a measurement on one of them will instantly disrupt the state of the other. Thus your quantum UNIX would have the 'ln' command but not 'cp' ( 'cp -l' is ok ). Even more amusing is that this mandates that the disruption is non-deterministic. If it wasn't you could use it to transmit information and energy quicker than the speed of light, which is prohibited by relativity. So, if you thought lawmakers had trouble understanding how computers work, just wait until they get to deal with the question of who is liable for causing the de-coherence of a quantum system ( hint: you can't prove it unless you caused it ). Bring on the lawyers :P
now, everytime you try to measure the release date, it will change!
A goal is a dream with a deadline
Patent it for step 3 profit!
The main roadblock to keeping the gates unitary (i.e. keep the error rate low) is to have the switching occur faster than the decoherence time (the timescale over which the delicate superposition decoheres into a random probabilistic mixture). This is certainly a difficult issue to solve, but in principle it is possible. The small-scale quantum computers that have been built to date were able to solve small problems deterministically.
As a practical point, it may turn out to be very difficult to build a quantum computer... but as far as I know the intended designs of quantum computers are not to yield probabilistic answers and then to average them, but to maintain coherence long enough that the final answer is deterministic, with an acceptably small error rate.
...patents pending.
Bill Gates was heard that 64 qubites should be enough for everybody. However, the sentence changed to "640 qubites could be enough for somebody" immediately after being heard, following the uncertainity principle. We'll try to monitor the matter. Moreover, new Windows 2008 core was reported to be optimized and based on 64 qubit memory. This memory is based on elements with low halflife, thus the Windows 2008 codename, Un(vi)stable.
Don't worry, it will become entangled at some point. Or it might not. You can't really win.
which is totally what she said
How the hell would you error-check the data stored in qRAM? As soon as you read it to compare it to the ECC bit, it'd change! You'd end up with the most amazing computer ever, and it wouldn't be able to do anything useful for you, aside from giving you the wrong bloody answer all the time!
Quantum Storage? Every time you loaded a file, it'd change the contents. Even checking "Read Only" would irreversibly damage the contents... and think about the implications for Swapfiles!
The fundamentally probabilistic aspect in quantum mechanics is only in measurement (and even there, there are situations where measurement results are completely non-probabilistic; especially it's completely possible to emulate a classical computer on a quantum computer). For typical quantum algorithms, the only time you do a measurement, you do it at the very end. Especially this quantum RAM proposal does not in any way contain any measurement, therefore on an ideal quantum computer, it works completely deterministic. Especially, if your qubit pattern really adresses only one memory cell, it will be reliably fetched. But in general, your qubits will address a superposition of memory cells, and will therefore cause reading a superposition of values (there's still no randomness in here; only if you were to measure that stuff, you'd get randomness in; but even then, in the general case it's not a 50% chance to get the bit right; if that would the case, not only quantum computing, but any meaningful prediction in the quantum world would be completely impossible even from the start).
Now, in the real world, there are random influences besides the fundamental randomness in measurement (simply because you cannot completely isolate the system from the environment), and those influences are indeed a big problem of quantum computing. Now that's exactly the point of what the authors did: From what they claim, their scheme is more robust against those influences because there are less gates interacting with the qubits, i.e. less ways for the environment to mess with the system.
BTW, they also claim their memory adressing scheme could give energy savings on classical computers (since classical computers provably can be built, their work could be useful even if there will never be a single quantum computer of more than a few qubits).
Yeah, but it's really going to suck trying to explain to my parents why this quantum memory doesn't keep that photo if something goes terribly wrong.
Every time I start to have faith in humanity, I ruin it by driving to work between 7 and 8 am.
User: My box seems to not want to boot, I think it's this new ram.
Tech Help: Your ram may, or may not, be dead. We will not know until you open the box, at which point in time it will be decided.
User: Thanks captain obvious.
I do not respond to cowards. Especially anonymous ones.
Okay, so how fast is it? Is it faster than the current RAM we use, at the size we use it? I mean, this may SEEM like a dumb question, but my understanding is that reading the response from a "quantum query" is non-trivial. Does anyone know?
Tech-geek 1 : How much ram have you got in that rig?
Tech-geek 2 : I'm not sure...
Would this solve the memory-cpu bottleneck we currently have?
i mean,you can access any part of the Tree at any time instead of rolling by the entire tree?
if not,it should be called quantum tape or quantum stream or something like that,as there NO random access
I, for one, welcome our atomic-scale quantam overlords...
So, the cat isn't dead after all!
factor 966971: 966971
> would it be up or down?????
:-)
Neither and both, until we observe it
There was a time when movies had plots. So you knew who's ass it was, and why it was farting.
-Not Sure
Quantum porn will never catch on, since it swings both ways until you look at it. Whilst alright for bisexuals, this could result in some potentially fatal lower whiplash for the unprepared.
If the cat gets elektrocuted, he may or may not be dead.
Knowledge is power. Knowledge shared is power lost.
Yes, but how long until we can build Asimov's dream of a positronic robot? Seriously... surely that's the end aim of this: a few million tiny interconnected quantum processors to create a cool robot. Of course, we'd have to ensure that it respected human life:)
Actually, I have one right here if you'd care to take a look...
Any probabilistic computation device can be duplicated to get a better probability of a correct result. Think majority voting systems. Conventional computers already have a very high probability of getting the correct result, because of sheer number of particles being shuffled around per bit - Any quantum effects are swamped by the overall system.