6 ms·

What is possible on these kind of processors at the minute?

hulitu 5y ago
We cannot know because if we check this will influence the result of the calculation.
freemint 5y ago
Even when facing specialized quantum circuits classical supercomputers are still more cost effective. Quantum computers can't solve any problems of sizes that occur in industry. There are huge problems with scaling up quantum computers and there are some reasons to doubt that we will ever be able to scale it up as much to break crypto or solve industrial problems.
- throwaways885 5y ago
  How cost effective were microprocessors in the 60s?
  - pverghese 5y ago
    Than you. Somebody speaks with some common sense. All major breakthroughs start small and are not cost effectvie immediately. People should be way more enthused that this is possible rather than talking about all the negatives.
    - spywaregorilla 5y ago
      I don't think it's true that all major breakthroughs start small, but more importantly, you have no basis for assuming this is a major breakthrough. The issues stated here are not just cost problems of scaling up, but theoretical problems of what this technology can accomplish.
  - wongarsu 5y ago
    They might have stayed cost prohibitive for a lot longer if it weren't for the Apollo program buying up everything they could get
  - Comevius 5y ago
    They became cost effective in a few years. The average price per integrated circuit dropped from $50 in 1962 to $2 in 1967. By then Moore's Law was established. At the end of the decade we had hundreds of transistors on a chip. At the early 70s we already had general-purpose microprocessors with thousands of transistors. Quantum computing is being researched since the 1980s without a theoretical understanding whether they can be built at a practical scale.
  - dekhn 5y ago
    As pointed out by others, they were very cost effective. And they replaced vacuum tubes, which were fragile. But, the most important thing is that they immediately solved a problem (ballistic trajectory calculations in missiles) and therefore had an industrial use which led to a virtuous cycle of improvement. Quantum computers aren't useful; they're still searching for a use.
    - vbezhenar 5y ago
      I think that NSA and similar organizations would be interested in breaking encryption algorithms. Imagine some old archive encrypted by RSA which contains useful data. Also that means that encrypting anything valuable with quantum-unresistant algorithm and storing it in an unsafe place is not wise even today.
      - dekhn 5y ago
        We can assume that NSA maintains a hardware portfolio and that quantum computers would be a tiny part of that. I'm sure NSA has been able to decrypt RSA for a while. https://www.reuters.com/article/us-usa-security-nsa-rsa/exclusive-nsa-infiltrated-rsa-security-more-deeply-than-thought-study-idUSBREA2U0TY20140331 https://www.reuters.com/article/us-usa-security-nsa-rsa/excl... and https://en.wikipedia.org/wiki/Bullrun_(decryption_program) https://en.wikipedia.org/wiki/Bullrun_(decryption_program) and https://www.pcworld.com/article/2064960/google-strengthens-its-ssl-configuration-against-possible-attacks.html https://www.pcworld.com/article/2064960/google-strengthens-i... The history of decryption hardware is fascinating and filled with practical solutions, which QC is not.
  - _hl_ 5y ago
    The two aren't really related. It's a bit like saying "we were able to build computers, surely we can also build <insert arbitrary tech thing>". Still waiting for that high-temperature superconductor. As far as I understand it, the biggest problem is getting the manufacturing precision good enough. The more you scale, the more precise the manufacturing needs to be, which was never really a problem with microprocessors.
FartyMcFarter 5y ago
At the moment I believe they can only solve toy problems (like factoring the number 15 - it's apparently 3 * 5 with high probability) and/or ones that are specifically contrived to show quantum supremacy.
- nradov 5y ago
  What is the probability that 15=2*7?
  - FartyMcFarter 5y ago
    Slightly lower :)
  - amelius 5y ago
    Exactly 1, for large values of 2.
    - rbanffy 5y ago
      Or low values of 15. We must consider that other possibility.
    - Frost1x 5y ago
      I'd say exactly 1 for very moderate or average values of 2. The very large values might converge on 21 but I'll have to flip a coin on it.
  - Razengan 5y ago
    What is 2? What is 7?
    - ohhhhhh 5y ago
      now youre asking the right questions lol
      - Razengan 5y ago
regularfry 5y ago
If you want a transistor-count analogy, it's low double-digits. Think 74-series logic.
sebzim4500 5y ago
It will be a while before anything of value can be done on a quantum processor. For now, all that will be done are increasingly convincing demonstrations of 'Quantum Supremacy'. This means that the quantum processor will solve a problem that is believed to be intractable on a classical computer. These problems are very contrived though, no one will actually care about the results of the computations.

We cannot know because if we check this will influence the result of the calculation.

Even when facing specialized quantum circuits classical supercomputers are still more cost effective. Quantum computers can't solve any problems of sizes that occur in industry. There are huge problems with scaling up quantum computers and there are some reasons to doubt that we will ever be able to scale it up as much to break crypto or solve industrial problems.

throwaways885 5y ago
How cost effective were microprocessors in the 60s?
- pverghese 5y ago
  Than you. Somebody speaks with some common sense. All major breakthroughs start small and are not cost effectvie immediately. People should be way more enthused that this is possible rather than talking about all the negatives.
  - spywaregorilla 5y ago
    I don't think it's true that all major breakthroughs start small, but more importantly, you have no basis for assuming this is a major breakthrough. The issues stated here are not just cost problems of scaling up, but theoretical problems of what this technology can accomplish.
- wongarsu 5y ago
  They might have stayed cost prohibitive for a lot longer if it weren't for the Apollo program buying up everything they could get
- Comevius 5y ago
  They became cost effective in a few years. The average price per integrated circuit dropped from $50 in 1962 to $2 in 1967. By then Moore's Law was established. At the end of the decade we had hundreds of transistors on a chip. At the early 70s we already had general-purpose microprocessors with thousands of transistors. Quantum computing is being researched since the 1980s without a theoretical understanding whether they can be built at a practical scale.
- dekhn 5y ago
  As pointed out by others, they were very cost effective. And they replaced vacuum tubes, which were fragile. But, the most important thing is that they immediately solved a problem (ballistic trajectory calculations in missiles) and therefore had an industrial use which led to a virtuous cycle of improvement. Quantum computers aren't useful; they're still searching for a use.
  - vbezhenar 5y ago
    I think that NSA and similar organizations would be interested in breaking encryption algorithms. Imagine some old archive encrypted by RSA which contains useful data. Also that means that encrypting anything valuable with quantum-unresistant algorithm and storing it in an unsafe place is not wise even today.
    - dekhn 5y ago
      We can assume that NSA maintains a hardware portfolio and that quantum computers would be a tiny part of that. I'm sure NSA has been able to decrypt RSA for a while. https://www.reuters.com/article/us-usa-security-nsa-rsa/exclusive-nsa-infiltrated-rsa-security-more-deeply-than-thought-study-idUSBREA2U0TY20140331 https://www.reuters.com/article/us-usa-security-nsa-rsa/excl... and https://en.wikipedia.org/wiki/Bullrun_(decryption_program) https://en.wikipedia.org/wiki/Bullrun_(decryption_program) and https://www.pcworld.com/article/2064960/google-strengthens-its-ssl-configuration-against-possible-attacks.html https://www.pcworld.com/article/2064960/google-strengthens-i... The history of decryption hardware is fascinating and filled with practical solutions, which QC is not.
- _hl_ 5y ago
  The two aren't really related. It's a bit like saying "we were able to build computers, surely we can also build <insert arbitrary tech thing>". Still waiting for that high-temperature superconductor. As far as I understand it, the biggest problem is getting the manufacturing precision good enough. The more you scale, the more precise the manufacturing needs to be, which was never really a problem with microprocessors.

FartyMcFarter 5y ago

At the moment I believe they can only solve toy problems (like factoring the number 15 - it's apparently 3 * 5 with high probability) and/or ones that are specifically contrived to show quantum supremacy.

nradov 5y ago
What is the probability that 15=2*7?
- FartyMcFarter 5y ago
  Slightly lower :)
- amelius 5y ago
  Exactly 1, for large values of 2.
  - rbanffy 5y ago
    Or low values of 15. We must consider that other possibility.
  - Frost1x 5y ago
    I'd say exactly 1 for very moderate or average values of 2. The very large values might converge on 21 but I'll have to flip a coin on it.
- Razengan 5y ago
  What is 2? What is 7?
  - ohhhhhh 5y ago
    now youre asking the right questions lol
    - Razengan 5y ago

regularfry 5y ago

If you want a transistor-count analogy, it's low double-digits. Think 74-series logic.

sebzim4500 5y ago

It will be a while before anything of value can be done on a quantum processor. For now, all that will be done are increasingly convincing demonstrations of 'Quantum Supremacy'. This means that the quantum processor will solve a problem that is believed to be intractable on a classical computer. These problems are very contrived though, no one will actually care about the results of the computations.