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Two-Photon Walk a Giant Leap For Quantum Computing
ElectricSteve writes "Research conducted at the University of Bristol means a number of quantum computing algorithms may soon be able to execute calculations of a complexity far beyond what today's computers allow us to do. The breakthrough involves the use of a specially designed optical chip to perform what's known as a 'quantum walk' with two particles ... and it suggests the era of quantum computing may be approaching faster than the scientific establishment had predicted. A random walk – a mathematical concept with useful applications in computer science – is the trajectory of an object taking successive steps in a random direction, be it over a line (with only two possible directions) or over a multi-dimensional space. A quantum walk is the same concept, but translated to the world of quantum computing, a field in which randomness plays a central role. Quantum walks form an essential part of many of the algorithms that make this new kind of computation so promising, including search algorithms that will perform exponentially faster than the ones we use today."
We soon need to certify in quantum-mechanical logic to write software?
Any good resources?
I think we can keep recursing like this until someone returns 1
into a bar... wait... where am I?
Unless they perfect a neural interface I'm pretty sure you won't be getting completely immersive games... But I'd be interested in seeing what kind of crazy fractal-based graphics and random world maps they can make with this tech.
I do not respond to cowards. Especially anonymous ones.
Here's how it looks under a microscope
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According to the quantum computing video from a while ago (I think it was 90 minutes or something, I just watched 20), a quantum computer is designed for the problem it solves- they aren't general purpose like the processors in use today. As far as I understood from the video*, quantum computers are mostly just useful for doing calculations related to quantum physics.
*If I'm wrong/misleading, please correct me.
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Well, it seems there is no article yet to be read, and I couldn't understand anything from the press release. What does it mean a "one photon quantum walk", and what is the difference from any other kind of transformation that happens on a photon? Also, what is the difference of "two-photon quantum walk" and normal interference?
Or, in other words, what did they actualy do?
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Better search should help with fun at home
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
Unless they perfect a neural interface.
I believe you mean until they perfect the neural interface. If the story is true, the neural interface seemed a lot closer to reality than practical quantum computing until about 3 mins ago.
I don't know how many years on this Earth I got left. I'm going to get real weird with it. - Frank Reynolds
Screw immersive gaming. How is this going to help me watch porn in the interweb.
Because people always get it wrong every time a QC article hits slashdot, here's a link to my previous, highly-modded (upwards) post on QC:
http://slashdot.org/comments.pl?sid=1285849&cid=28520061
Quantum computers can do some cool things, but mostly solve problems no one cares much about (except a few of us mathematicians)
Summary is wrong. Quantum algorithms cannot provide "exponential" speedup of any problem. If they could, we would be able to [probably] solve NP-complete problems with quantum computers, and that hasn't been proven yet. The best they can do is "super-polynomial" speedup of classical algorithms.
Google "quantum algorithm zoo" to see all the known algorithms and their speedups (and how unexciting most of them are).
Seams like it about time to start putting 5 years of real world quantum programming experence on the old resume.
I believe the technical jargon makes it sound much more complicated than it is. Understanding what the scientists did requires knowing about 'random walks' and their significance. Think of a typical processor working on a problem that involves random walk sequences. Now imagine if that was replaced by getting 2 photons to calculate the 'random walk' part of the problem -- speed is massively increased, and quantum superpositions are now hopefully being utilized. The problem, in many cases, may have just become exponentially easier and faster.
Just another "small step" out of thousands we are blessed with being able to witness. Patience is a virtue.
Peter Gibbons: What would you do if you had a million dollars?
Lawrence: I'll tell you what I'd do, man: two photons at the same time, man.
Been waiting for this for over 20 years. Though I'll be sure to skip rev. 1.
Come on, Scott Bakula was taking random quantum walks back in the late 80s, get with the times people!
Monstar L
Grover's search algorithm gives only a quadratic speedup.
Based on this article, I would count on quantum computing having a big impact on computer graphics. A quantum algorithm that can crunch matrices exponentially faster than current techniques would be as important for graphics (and many other fields) as a quantum computer's ability to quickly factor large numbers would be for cryptography.
I'm glad you've asked that question, here's how it works:
First you have to rub one off, then by the Magic of Quantum(TM) the girl inside the video gets a bunch of milk products on some part of her body right afterwards. So it's like being there, but the technology scales simultaneously to millions of web surfers in their parents basement!
The probability of a result being incorrect is always nonzero, quantum computing or not.
... the neural interface seemed a lot closer to reality than practical quantum computing until about 3 mins ago.
So what you're saying is that we couldn't know where we were until we opened our eyes?
Two photons walk into a bar, orders a round of IPA and asks "How much do we owe?"
The barkeep says "For you? No charge."
Finally we'll be able to run bogosort efficiently
Let me provide some context. This research group specializes in manufacturing arbitrary waveguide structures on chips, then coupling particular quantum states of light into them. The idea is to turn a large optical table worth of mirrors into a tiny chip. What they have done here, is allowed a two photon input state to interfere with itself in the waveguide structure.
While interesting technically, it isn't exactly a huge leap forward because the interaction is linear. What's needed for deterministic quantum computation with light is a very non-linear process. The waveguide structure can replace a large number of mirrors and compact the optics into a tiny space but, at the end of the day, mirrors aren't all that interesting for quantum computation. It is, however, worthwhile because of the impressive miniaturization and the technical challenge of working with quantum light in such tiny structures. A strong non-linear component will be needed for true optical quantum computation, but chips like these show a lot of promise for handling a lot of state preparation and measurement.
So if this is the future...where's my jet pack?
With your eyes open or closed, you're still in your parent's basement.
I tried to think of a good sig, and this wasn't it.
"It's safe to turn of the universe now" -Windows, no wait, Wormhole 2095.
"General Protection Fault?!?! You- You.... AAAAAAAAAAAAAAAAAHHHHH!!!!!"
Here be signatures
Two photons walk into a bar...
Wait, didn't Brian Greene already tell this joke?
Don't do it! I've tried one of those newfangled Quantum Consoles and ended up in this Universe. Can I get out now? Please?
So far, claims from quantum computing researchers hungry for funding resemble that of some other areas that have consistently not delivered for the last 50 years or so. All these isolated demonstrations mean nothing for quantum computing, because different from normal computers, you cannot build them up from parts you understand. A quantum computer is always only one unit, there are no modules or sub-components. Compare that with a traditional computer and it becomes obvious that the only proof of scalability for a quantum computer is to build the size you claim you can. And until that is done, everything else is basically wishful thinking. This also means that at this time, it is quite possible that quantum computers of meaningful power are fundamentally infeasible in this universe.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.