How close are practical quantum computers really?

[Anaxagoras]

Why the age of quantum computing is nearer than you think

Tech-buffs, investors, IT industrialists, and boffins alike eagerly await the day when the science of quantum computing yields practical technology. Physicists of the Max Planck Institute of Quantum Optics (MPQ), recently published research that, they believe, has brought that pivotal day closer.

For many years, physicists have sought to create an information network far superior to today's by exploiting quantum phenomena. The team of German researchers have constructed the first vital component of such a network: a link between two atomic nodes over which information can be received, sent, and stored using a single photon. Successful exchanges of information recently took place in Garching, Germany, between two MPQ labs connected by a 60-meter fiber-optic cable. Though only a prototype, this rudimentary network could be scaled up to more complex and distanced quantum networks. The team reports their research in Nature.

The idea of quantum computing was introduced by the physicist Richard Feynman in 1982. The essential unit of classical computing, the bit, is binary. Like a light switch, it's either on or off, 1 or 0. The quantum bit, by contrast, can be 1, 0, or a mix of both states – this last state being like a flipped coin that's still spinning in the air.

The usefulness of this extra dimension seems, at first pass, more confusing than anything else, but it actually creates an new opportunity to represent data. Whereas a trillion classical bits can hold 2⁴³ on/off values, a mere 200 quantum bit, or qubits, as they are known, could represent 2²⁰⁰ values. This new capacity would allow future computers to do involved calculations at nearly unthinkable speeds, and solve problems that are currently unsolvable. The technological implications are too many to list, which suggests why there's such excitement surrounding the field.

[Doctor X]

It is difficult to determine. . . .

--J.D.

[Anaxagoras]

:lol:

[Rob Lister]

And for the skeptical component

http://www.dwavesys.com/en/dw_homepage.html

I don't have it in me to research them. Mostly because I don't have it in me to 'get' quantum computing. There's some level of fundamental understanding I'm either missing or not.

http://tph.tuwien.ac.at/~oemer/doc/structquprog.pdf

Above if you have a fundamental want for a fundamental understanding. Good luck.

[Cool Hand]

Schrödinger's Mac? It's awesome and it sucks because Steve Jobs was an egomaniac at the same time until you turn it on. Then you find out you should have saved the Apple tax and just gotten a cheap PC instead.

CH

[DrMatt]

I'm still hoping for a graphene-based system without all the weird stuff and heat loss.

[Anaxagoras]

Researchers claim quantum breakthrough

Researchers say they have designed a tiny crystal that acts like a quantum computer so powerful it would take a computer the size of the known universe to match it.

Details of the crystal, which is made up of just 300 atoms, are published today in the journal Nature.

Wow.

And he adds that there is still plenty of work to be done before quantum computers start appearing on desks in homes and offices.

"The central element is something like a millimetre in diameter, 300 atoms that are suspended in space," says Biercuk.

"But of course everything depends on a huge amount of technical infrastructure around it. There are vacuum chambers and pumps and lasers, and all of that takes up something like a room."

[Doctor X]

Your new laptop:

http://timecheapskate.files.wordpress.c ... .jpg?w=576





We hope to have it in Technicolor [Tm.--Ed.] soon. . . .

--J.D.

[DrMatt]

Your new laptop might be a dumb terminal to something like that.

[Anaxagoras]

Another advance

http://m.tgdaily.com/trendwatch-feature ... it-created

Sorry for the mobile link.

[DrMatt]

Right, that's me driving: Auto-Matt...

[ed]

Pillory is holding out for an alcohol based computing system. :D

[Anaxagoras]

Some recent news on the quantum computer front:

http://www.techradar.com/news/computing ... rd-1326213

And this:

http://www.livescience.com/55642-reprog ... eated.html

I don't know if this means practical quantum computers are just around the corner or if I'll be bumping this thread again in 4 years with another story about the latest 'breakthrough' published in Nature.

[Tez]

I don't know if this means practical quantum computers are just around the corner or if I'll be bumping this thread again in 4 years with another story about the latest 'breakthrough' published in Nature.

you will be bumping this thread in 4 years (if you still care). I invest a lot of time (and other peoples money) in trying to build one and its a serious engineering challenge as well as a basic physics research opportunity.

Hopefully you do still care - having a QC will let us solve problems we don't even bother contemplating trying to simulate on a classical computer at present (eg problems in biochem/quantum chemistry/material science) and so the potential for these computers is difficult to quantify. It really is presently difficult to quantify what the upside is. I guess the same was true of regular computing at an early stage.

[Dragline]

Thread is filled with men who got their mind right.

[Witness]

And AC will want a 16-quantum-core machine. :shock:

[Anaxagoras]

CES: IBM announces Q System One, a quantum computer in a 9ft cube

https://d3w2mpp70f6o8z.cloudfront.net/m ... th-880.jpg

I guess this means we're at the Eniac stage of quantum computing. A 9-foot cube. Still, the thing exists. Like the early computers, it's not at the stage where you or I can afford one. Nor would I have the faintest idea what to do with it if I did have one. But I'm happy that they exist and that presumably somebody will know how to use them.

[Doctor X]

Nor would I have the faintest idea what to do with it if I did have one.

What you and all men do: look for tentacle porn.

--J.D.

[Nyarlathotep]

They are only about 6 inches away, but very very small

[Witness]

https://d3w2mpp70f6o8z.cloudfront.net/m ... th-880.jpg

Does it brew good espresso? :P

[Anaxagoras]

Interesting analysis from an actual scientist:



The video description has links to some of the articles and resources mentioned in the video.

The quantum hype cycle, revisited (physicsworld)

The quantum computing bubble (Financial Times)

Quantum Computing Hype is Bad for Science (Professor Victor Galitski via Linkedin)

Crazy headlines abound: "quantum computing will change life as we know it," "quantum computing will solve global warming," "Quantum computing will revolutionize science and industry," etc etc. These statements are not based on any research or reality at all, they are not even wishful thinking. The number of known quantum algorithms, which promise advantage over classical computation, is just a few (and none of them will "solve global warming" for sure). More importantly, exactly zero such algorithms have been demonstrated in practice so far and the gap between what’s needed to realize them and the currently available hardware is huge, and it's not just a question of numbers. There are qualitative challenges with scaling up, which will likely take decades to resolve (if ever).

[Anaxagoras]

I don't know if this means practical quantum computers are just around the corner or if I'll be bumping this thread again in 4 years with another story about the latest 'breakthrough' published in Nature.

This thread is now over 10 years old, and it's pretty clear by now that "practical quantum computers" are still a long way away. A bit like fusion energy. Probably decades, not years away.

Anywho, here's the latest 'breakthrough' published in Nature. It has to do with a way to reduce or compensate for the error rate in q-bits, which is one of the main problems facing the technology.

Suppressing quantum errors by scaling a surface code logical qubit Published: 22 February 2023

Practical quantum computing will require error rates well below those achievable with physical qubits. Quantum error correction1,2 offers a path to algorithmically relevant error rates by encoding logical qubits within many physical qubits, for which increasing the number of physical qubits enhances protection against physical errors. However, introducing more qubits also increases the number of error sources, so the density of errors must be sufficiently low for logical performance to improve with increasing code size. Here we report the measurement of logical qubit performance scaling across several code sizes, and demonstrate that our system of superconducting qubits has sufficient performance to overcome the additional errors from increasing qubit number.

A normal computer would be completely unusable if it had even a small "error rate" in the ones and zeros that tell it what to do and record information to be reproduced.

[ed]

The implications for AI render these errors irrelevant.

That is the future of this stuff.

You could also have some arbitrary large number of computers working on the same problem and passing the consensus answer on.

It is also a model for diversity hiring. If you simply increase the number of unqualified people working on a problem then take the consensus you might approximate truth. Which is government now I suppose.

[Pyrrho]

Yeah we need quantum computers so that we can create utter crap in higher volume in less time.

[ed]

You ever see Simone? With Pacino.

Simone is short for Simulation One, an AI entity. Worth a peek.

I have thought for the longest time that he future of gaming/entertainment would be the creation of realities that you could manipulate (and be in if you weren't lazy). And that entertainers, in this world, would not have contracts, they would be copyrighted assets of the production companies, ie. code.

You see Married a First Sight? Couples paired based on research. You could create a character in just the same way. Eesy peesy.

This would replace everythnig.

The guy who was the head of network at my old agency digs would introduce the new TV season to us and show the newest shows. Folks would moan at My Mother the Car or somesuch dreck. He said something that has stuck with me for decades:

There will never be dead air

[sparks]

Oh but there will be ed.

Takes idiots like me to keep them on the air. And they're just stupid enough to resist bringing up any new idiots.

Shooting themselves in the feet.

Greedy fuckers.

[Ben Trovado]

I don't know if this means practical quantum computers are just around the corner or if I'll be bumping this thread again in 4 years with another story about the latest 'breakthrough' published in Nature.

This thread is now over 10 years old, and it's pretty clear by now that "practical quantum computers" are still a long way away. A bit like fusion energy. Probably decades, not years away.

I had the same thought - it is like fusion power, which is (always) 5-10 years away.

[Doctor X]

I don't know if this means practical quantum computers are just around the corner or if I'll be bumping this thread again in 4 years with another story about the latest 'breakthrough' published in Nature.

This thread is now over 10 years old, and it's pretty clear by now that "practical quantum computers" are still a long way away. A bit like fusion energy. Probably decades, not years away.

I had the same thought - it is like fusion power, which is (always) 5-10 years away.

With my flying car.

– J.D.