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First Von Neumann Architecture Quantum Computer
holy_calamity writes "The first computers with a von Neumann architecture, where a processor has access to RAM, appeared in the 1940s. Now the first quantum computing system with a von Neumann design has been made, at University of California Santa Barbara. Their quantum processor made up of two superconducting quantum bits can use a 2-bit "quantum RAM" to save entangled bit values into."
I don't know, but someone will try to run Doom on it.
To be considered a Von Neumann architecture, the program code needs to be stored in the same ram as the working data. That's the whole point of it. Otherwise, it's a Harvard architecture.
Given that the total ram capacity seems to be 2 bits (though, in all fairness, the bits are qu), it seems implausible that a useful program could fit in it.
Though I have not actually read TFA, I'd say to be skeptical about this. What they probably meant is "It has RAM." Unfortunately they used the completely wrong term for this.
The term Von Neumann architecture has a variety of different meanings. One common meaning of the term is one in which instructions and data retrieval share a common bus. The original meaning was a bit more specific referring to a system that had a CPU, a separate memory for data and instructions, and input/output capability. Originally the real step forward was storing data and instructions together and treating them in some sense the same way which in many ways allowed a lot more flexibility in programming. Treating data and instructions the same way is something that still creates issues; SQL injection attacks are essentially just this: adding data that is formatted to look like instructions. But the upshot is that this use of the term- to use Von Neumann architecture to mean just having a working memory is a less common use of the term.
Moving on from there, the system in question uses superconductors to control qubits. This is one of a variety of different systems being proposed. For example, the most recent quantum computing article on Slashdot ahref=http://hardware.slashdot.org/story/11/08/31/1844252/Record-Low-Error-Rate-For-Qubit-Processorrel=url2html-5998http://hardware.slashdot.org/story/11/08/31/1844252/Record-Low-Error-Rate-For-Qubit-Processor> used ion traps. It is important to realize that different systems cannot be used together in any meaningful way. This means that improvements on any one type don't really carry over to the others. This is important if one is thinking in terms of when all this research will come together. A really good example of this is how early quantum computing used NMR systems http://en.wikipedia.org/wiki/Nuclear_magnetic_resonance_quantum_computer which was then abandoned due to scaling and other issues. A lot of what was learned with NMR systems could not be applied to later quantum computers.
Well at least I got a 'sir' out of it.
When the foot seeks the place of the head, the line is crossed. Know your place. Keep your place. Be a shoe.
May be a lot? Try it yourself.. 2 times 2.
which is totally what she said
is that because copying is stealing?
That's what this computer is good for.
... which may be a lot but still it seems pretty useless at this point.
There was a time when people struggled to put 10 transistors on a chip. Valve-based computers of that era ran rings around the puny and useless transistorized systems. You have to start somewhere ...
How do you know what you can and can't do with this type of architecture if you don't make an attempt to turn whiteboard theories into real world proof? They are not building this thing to run Windows it is a research tool.
That's one small step forwards, backwards, both or neither for electrons and one indeterminate state for quantumkind.
Anons need not reply. Questions end with a question mark.
You can copy it, but it copies both a one and a zero. You don't know which it is until you look.
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