They have. Well - 0.5 isn't both on and off. It's just 0.5. But if it's an ordinary mechanical computer you can't expect the quantum superposition of states of an analogue computer.
This is a somewhat forgotten episode of computing.
If you used the word "computer" in 1950, this is what they would think you are talking about. It's not a programmed Babbage type mechanical computer - rather - is an analogue machine, doesn't use numbers internally at all. Skip to 1.26 to see the computer in action. Just a minute or two of it.
See also my answer Robert Walker's answer to Is it possible that an alien civilization has completely different mathematics than ours? Is mathematics absolute? - rather long but I ask at one point if ET mathematicians might develop with no idea of number as we have it, and use analogue computers instead of digital ones.
Or, you might mean, Fuzzy logic which is used a fair bit, but can be simulated adequately on an ordinary digital computer.
The thing that makes a quantum computer special is that it can explore qbits that can be in multiple states at once - entangled with other qbits.
In principle this could make it much faster at some problems, e.g. factorizing numbers. The results so far aren't that impressive, the record is 143, and then 56153, that last one used a special trick that only works for very few numbers. Shor's algorithm - New largest number factored on a quantum device is 56,153.
But in principle a quantum computer could hugely outperform any classical computer for this problem, factorizing a number in seconds that you might need entire lifetime of the universe and still not factorize by ordinary methods.
A Hitchhikers Guide to Quantum Computing
This is a somewhat forgotten episode of computing.
If you used the word "computer" in 1950, this is what they would think you are talking about. It's not a programmed Babbage type mechanical computer - rather - is an analogue machine, doesn't use numbers internally at all. Skip to 1.26 to see the computer in action. Just a minute or two of it.
At 1:45 "If you look inside a computer, you find an impressive assembly of basic mechanisms. Some of them are duplicated many times in one computer"
Wikipedia article about it, range keeper.
See also my answer Robert Walker's answer to Is it possible that an alien civilization has completely different mathematics than ours? Is mathematics absolute? - rather long but I ask at one point if ET mathematicians might develop with no idea of number as we have it, and use analogue computers instead of digital ones.
Or, you might mean, Fuzzy logic which is used a fair bit, but can be simulated adequately on an ordinary digital computer.
The thing that makes a quantum computer special is that it can explore qbits that can be in multiple states at once - entangled with other qbits.
In principle this could make it much faster at some problems, e.g. factorizing numbers. The results so far aren't that impressive, the record is 143, and then 56153, that last one used a special trick that only works for very few numbers. Shor's algorithm - New largest number factored on a quantum device is 56,153.
But in principle a quantum computer could hugely outperform any classical computer for this problem, factorizing a number in seconds that you might need entire lifetime of the universe and still not factorize by ordinary methods.
A Hitchhikers Guide to Quantum Computing
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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