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D-Wave Defies World of Critics With ‘First Quantum Cloud’

wired.com

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Re: D-Wave Defies World of Critics With ‘First Quantum Cloud’

#11

Post by onemoreact »

dljsjr wrote: post #7
julian37 wrote: post #5

The classic example is figuring out the most efficient route for a traveling salesman going to multiple destinations. [...] For example, if you have six destinations, there are 64 possible combinations. If you have 20 destinations, there are 1,048,576 possible combinations. That's incorrect, the number of combinations for N destinations is N!, not 2^N. So for 6 destinations there are 720 combinations and for 20 there…

Only using naive algorithms. You can get it down to 2^n time complexity by increasing the space complexity and applying dynamic programming techniques. https://en.wikipedia.org/wiki/Travelling_salesman_problem#Ex...

I always find it funny when 2^n is viewed as 'good news'. I realize it's better than the other options, but it still feels like a doctor saying great news you've got cancer!

Re: D-Wave Defies World of Critics With ‘First Quantum Cloud’

#14

Post by Tossrock »

adrianN wrote: post #2

This article is full of bullshit claims about the power of quantum computers. There are no known quantum algorithms for NP-complete problems like the travelling salesman problem mentioned in the article that run faster than exponential time. Quantum computers in general don't consider an exponential number of possible solutions, or if they do, you can't extract the true solution from the quantum state.

There seems to be a general misunderstanding of what quantum computers are capable of in the public mind, or at least that slice of it that is even aware of quantum computers' existence. I was just reading Hominids by Robert J Sawyer and it involves a quantum computer. He describes how it 'checks every possible answer simultaneously' to find the prime factors of a number instantaneously...which of course is not how Shor's algorithm actually works.

Re: D-Wave Defies World of Critics With ‘First Quantum Cloud’

#15

Post by davorak »

> On some level, Rose understands the criticism. “It’s the same basic human reaction that everybody has to something that someone says that sounds outrageous,”

I think it less about it being outrageous and more about the fact that he and the company's press releases sound more like infomercials then technological descriptions. Which historically seems to happen with pseudoscience based companies.

Re: D-Wave Defies World of Critics With ‘First Quantum Cloud’

#17

Post by loboman »

dustingetz wrote: post #8

> That same month, mega defense contractor Lockheed Martin bought a D-Wave quantum computer and a support contract for $10 million. lol, i used to work at LM advanced research, LM consistently blows 10 mil over 3 ears on stupid dead end projects and nobody even blinks. This is not a criticism of LM so much as it gives us insight into the size of budget and scope of projects the work with. they did 45bn revenue in 201…

Are you saying that Lockheed had 45bn revenue in 2011 from wikipedia? how does that work?

Re: D-Wave Defies World of Critics With ‘First Quantum Cloud’

#18

Post by pcvarmint »

"The great mathematician and founding figure of computer science, Alan Turing, showed that it is impossible to eliminate all errors from software."

Oh? I thought he only proved that it's impossible for an algorithm to determine whether an arbitrary program will halt -- not whether all errors can be eliminated from software.

Re: D-Wave Defies World of Critics With ‘First Quantum Cloud’

#19

Post by brimpa »

It seems that every time I read articles about quantum computing, the increase in computing power is described with gaping hole:

1. Qubits can be 1 and 0 at the same time

2. ...

3. Solve hard problems!

Can someone provide a link that fills in the middle somewhat? Preferably, aimed at an audience with something closer to undergrad engineering degree and than a PhD?

Re: D-Wave Defies World of Critics With ‘First Quantum Cloud’

#20

Post by aaronblohowiak »

loboman wrote: post #17
dustingetz wrote: post #8

> That same month, mega defense contractor Lockheed Martin bought a D-Wave quantum computer and a support contract for $10 million. lol, i used to work at LM advanced research, LM consistently blows 10 mil over 3 ears on stupid dead end projects and nobody even blinks. This is not a criticism of LM so much as it gives us insight into the size of budget and scope of projects the work with. they did 45bn revenue in 201…

Are you saying that Lockheed had 45bn revenue in 2011 from wikipedia? how does that work?

The parent is citing wikipedia. Saying "per wikipedia" is using "per" to mean "according to", not using it to mean "for each"

http://en.wikipedia.org/wiki/Lockheed_martin

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