Two-photon walk a giant stride for quantum computing

[imadaman]

[img]http://images.gizmag.com/hero/gizmag-podcast-4.png[/img]
[url=http://www.gizmag.com/two-photon-walk-quantum-computing/16394/]Source[/url]
[release][img]http://images.gizmag.com/hero/two_photon_quantum_walk-1.jpg[/img]
The photonic chip next to a UK penny. The chip contains micrometer and sub-micrometer features and guide light using a network of waveguides. The output of this network can be seen on the surface of the chip.

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.

For their experiments, the researchers designed a network of optical circuits in a silicon chip, and then managed to make two photons perform a quantum walk along the network at the same time. Other researchers had previously achieved quantum walk for a single photon, but this was the first time that a quantum walk was achieved with two photons.

The task was challenging because, in order for the algorithm to perform correctly, the two particles need to be exactly identical and the researchers needed to account for how the two particles would interfere with each other as they moved throughout the circuits. Going from two to more photons, however, should be relatively straightforward as the same principles would apply.

But why go through all this trouble just to add a few more particles? The answer is that with every photon added to the system, the number of outcomes increases exponentially. So, if a single-photon quantum walk has 10 possible outcomes, a two-photon walk will have 100 possible outcomes, and so on. This allows the researchers to simulate highly complex situations that are currently outside of the number-crunching possibilities of today's fastest supercomputers.

The team is planning to apply their results to develop new and more sophisticated simulation tools, by increasing both the number of photons in the system and by using larger circuits. In the long run, a multi-photon quantum walk could be used to reliably simulate and thus better understand physical phenomena governed by the laws of quantum mechanics where photons are involved, such as photosynthesis and photon absorption in solar cells, as well as to develop exponentially faster search engines.

"Using our new technique, a quantum computer could, in less than ten years, be performing calculations that are outside the capabilities of conventional computers," commented Professor Jeremy O'Brien, Director of the Centre for Quantum Photonics. The research will be published in tomorrow's issue of the journal Science.[/release]

[BlueChameleon]

I'm starting a physics degree at the University of Bristol next month. They have a whole centre for quantum research similar to that.

Can't wait to contribute to stuff like this!

[thirty9th]

[quote="article]...as well as to develop exponentially faster search engines.[/quote]

5 years from now; Google Quantum.

[bobsmit]

Science makes me giddy.

[Mr. Scorpio]

Here it comes, the positronic brain.

[Redcow17]

[QUOTE=thirty9th;24890075]5 years from now; Google Quantum.[/QUOTE]

Even though it only takes a fraction of a second now..

[DarkSpider]

This is the scary bit. Quantum computing AFAIK can pretty much allow virtually infinite amounts of computing power if i'm not mistaken.

[MrOwn1]

[QUOTE=DarkSpider;24890282]This is the scary bit. Quantum computing AFAIK can pretty much allow virtually infinite amounts of computing power if i'm not mistaken.[/QUOTE]

:psyboom:

[GodKing]

"Ready quantum tohpedoes.."

[img]http://cortexmeltdown.files.wordpress.com/2009/04/picard.gif?w=384&h=256[/img]

"Fiyah!"

Had to make a Star Trek reference. Article reminds me of it so much.

[Pythagoras]

[QUOTE=DarkSpider;24890282]This is the scary bit. Quantum computing AFAIK can pretty much allow virtually infinite amounts of computing power if i'm not mistaken.[/QUOTE]

Scary isn't the right word at all.

Try incredible.

[smallpants]

[QUOTE=thirty9th;24890075]5 years from now; Google Quantum.[/QUOTE]

it knows what your about to search before you even open your browser

[GodKing]

[QUOTE=xgman236x;24890954]it knows what your about to search before you even open your browser[/QUOTE]

It turns your computer on and displays the results for you before you even think about searching and getting up to go do it.

[DarkSpider]

But in the wrong hands dude. War games

[Biotoxsin]

[QUOTE=DarkSpider;24890282]This is the scary bit. Quantum computing AFAIK can pretty much allow virtually infinite amounts of computing power if i'm not mistaken.[/QUOTE]

The problem with 'virtually unlimited' is theres no such thing.

Think about calculating pi. If rather than calculating lets say, 500,000 digits a second, you calculate 5x10^15 digits a second, the leap is great, but still not as good as it could be. You could always go farther, faster. (values are completely for example)

Other example: Physics simulation. I'd like to simulate the movement every particle in a virtual universe. Not possible, you present the problem of light having a max speed.

I'd imagine if you were to go back to 1965 with your computer, they'd refer to it as having 'Virtually infinite' information processing capabilities.

[smallpants]

[QUOTE=GodKing;24890978]It turns your computer on and displays the results for you before you even think about searching and getting up to go do it.[/QUOTE]

it reminds you to breath, and poop, and piss, and jack off, and make a mediocre FP post.

[advancedlamb]

[QUOTE=Biotoxsin;24891024]The problem with 'virtually unlimited' is theres no such thing.

Think about calculating pi. If rather than calculating lets say, 500,000 digits a second, you calculate 5x10^15 digits a second, the leap is great, but still not as good as it could be. You could always go farther, faster. (values are completely for example)

Other example: Physics simulation. I'd like to simulate the movement every particle in a virtual universe. Not possible, you present the problem of light having a max speed.

I'd imagine if you were to go back to 1965 with your computer, they'd refer to it as having 'Virtually infinite' information processing capabilities.[/QUOTE]

Infinite computing power would mean it would take no time at all to do something, like it would calculate pi...before...you...start calculating it?

[DarkSpider]

[QUOTE=Biotoxsin;24891024]The problem with 'virtually unlimited' is theres no such thing.

Think about calculating pi. If rather than calculating lets say, 500,000 digits a second, you calculate 5x10^15 digits a second, the leap is great, but still not as good as it could be. You could always go farther, faster. (values are completely for example)

Other example: Physics simulation. I'd like to simulate the movement every particle in a virtual universe. Not possible, you present the problem of light having a max speed.

I'd imagine if you were to go back to 1965 with your computer, they'd refer to it as having 'Virtually infinite' information processing capabilities.[/QUOTE]

True, but this is leaps and bounds beyond the increase from the 60's to the present decade. It's like going from 10 to 100, then 1000 to 1,000,000. Now imagine 1,000,000 going to 1,000,000,000,000,000,000,000+

It's a very large difference if you consider the first 40 years we went from 10 to 1,000,000, and then jumped to 1,000,000,000,000,000,000,000+

[catoffun]

[URL]http://news.techworld.com/operating-systems/3477/moores-law-is-dead-says-gordon-moore/[/URL]

[QUOTE]"In terms of size [of transistor] you can see that we're approaching the size of atoms which is a fundamental barrier,
but it'll be two or three generations before we get that far - but that's as far out as we've ever been able to see.
We have another 10 to 20 years before we reach a fundamental limit. By then they'll be able to make bigger chips and have transistor budgets in the billions."[/QUOTE]Think about combining those calculating capabilities, paired with human interface devices, on the biological level.

Matrix, Inception, Geek's ultamate fantasy type stuff.

[ironman17]

[QUOTE=DarkSpider;24890282]This is the scary bit. Quantum computing AFAIK can pretty much allow virtually infinite amounts of computing power if i'm not mistaken.[/QUOTE]
Does it mean I could run multiple instances of Crysis on Very High graphics with a couple of these chips?

[Paravin]

[QUOTE=ironman17;24894023]Does it mean I could run multiple instances of Crysis on Very High graphics with a couple of these chips?[/QUOTE]

Only one.

[Master117]

Two photons walk into a bar. The bartender sees them and says, "who's bright idea was this?"

[DSG]

I wonder if they'll become available to the public soon too

[Kab2tract]

Great, now AM from "I have No Mouth, and I must Scream" may become a reality.

[noctune9]

[QUOTE=Tetracycline;24891055]Infinite computing power would mean it would take no time at all to do something, like it would calculate pi...before...you...start calculating it?[/QUOTE]

So if you had a computer with infinite computing power, would it be able to finish a infinite loop? :v:

[DeanWinchester]

So when exactly do I get to be a biotic god?

[Ickylevel]

[QUOTE=Biotoxsin;24891024]The problem with 'virtually unlimited' is theres no such thing.

Think about calculating pi. If rather than calculating lets say, 500,000 digits a second, you calculate 5x10^15 digits a second, the leap is great, but still not as good as it could be. You could always go farther, faster. (values are completely for example)

Other example: Physics simulation. I'd like to simulate the movement every particle in a virtual universe. Not possible, you present the problem of light having a max speed.

I'd imagine if you were to go back to 1965 with your computer, they'd refer to it as having 'Virtually infinite' information processing capabilities.[/QUOTE]

Virtually unlimited means that you can calculate what you want as fast as you want. You could simulate the behavior of the universe using a precise enought model, but since the universe has probably some infinity in it , you couldn't simulate it completely. But it wouldn't matter. It would be good enought.

[editline]02:13PM[/editline]

Having a computer like this would be a bigger event than the return of Jesus Christ.

[Sickle]

FINALLY!

I'll be able to run Crysis on medium.

[DokVis]

[QUOTE=Sickle;24896381]FINALLY!

I'll be able to run Crysis on medium.[/QUOTE]

Pff, you dream too much, it will be on low.

[Number-41]

[QUOTE=BLUchameleon;24889588]I'm starting a physics degree at the University of Bristol next month. They have a whole centre for quantum research similar to that.

Can't wait to contribute to stuff like this![/QUOTE]

I'm also starting physics, but quantum stuff only starts next year for me.First gotta learn the basics

[joost1120]

I expected a joke. Two photons walk into a bar...