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Comment by FrojoS | Hacker News Reader

> By definition, a computer is a machine that processes and stores data as ones and zeroes.

No, of course thats only true for digital computers. Otherwise, what would be the point of the headline? Not a great article but interesting news.

I could imagine specialized computer for artificial neural networks (ANN) being commercially successful in the future. Not sure if this is what the people in this DARPA project are working on. As far as I can tell, there are a lot of breakthroughs in ANN's at the moment, especially in the realms of pattern (e.g. image) recognition: Ng: http://www.youtube.com/watch?v=ZmNOAtZIgIk Hinton: http://news.ycombinator.com/item?id=4403662

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> No, of course thats only true for digital computers.

Not even that. Computers with ternary instead of binary logic are possible:

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

Quote:

"The only modern, electronic ternary computer Setun was built in the late 1950s in the Soviet Union at the Moscow State University by Nikolay Brusentsov […] IBM also reports infrequently on ternary computing topics (in its papers), but it is not actively engaged in it."

Which brings up a question I've always had. If a Quantum computer uses bits that are on, off, and both, can't this be simulated with a Ternary computer?

You need more classical resources to model a qubit in generality. This is because a qubit can be in the "0" state, the "1" state, or in any superposition between them. For a single qubit, you can describe an arbitrary superposition by two angles [1], each of which is a continuous real number. While you can't extract both of these parameters from a single measurement, a classical computer has to know both angles to simulate that qubit. Thus, it's more like that you need two floats to simulate a single qubit.

When you have more than one qubit, the requirements get much worse, as you can have superpositions over all of the possible classical states. When you work through the math, you find that you need a vector of 2^n - 1 complex floats to model a register of n qubits in full generality. Going from a classical bit to a classical trit does nothing to help with that exponential scaling.

[1]: http://en.wikipedia.org/wiki/Bloch_sphere

It's not just "both" it's 1 and 0 in any proportion. 97% 1 and 3% 0, 23% 1 and 77% 0, etc.

Many pre-digital computers are really interesting.

http://www.youtube.com/watch?v=rVOhYROKeu4

http://www.youtube.com/watch?v=T_xhMykK5Hw

http://www.youtube.com/watch?feature=endscreen&NR=1&...

> I could imagine specialized computer for artificial neural networks (ANN) being commercially successful in the future.

There are a few companies already commercializing this, CogniMem[0] is one that comes to mind. However, I haven't heard of any commercial scale "success" stories despite their first parts being built in 2008.

[0] http://www.cognimem.com/index.html

That was a really weak line to open with. I actually groaned and closed the tab as soon as I read it.

I had a similar issue. Some bit of my head just started swearing and shouting stuff about op-amps before I could get any further. That happens sometimes.

And it isn't even true of digital computers. Binary data can be interpreted as ones and zeroes, but it isn't inherently numerical.

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