A Simple Experimental Challenge?

Commenter Michael J. Biercuk asks about D-wave’s machine:

What is the fundamental experimental test which would demonstrate the system is not simply undergoing a classical, incoherent process?

Of course there are answers to this question which involve some technically fairly challenging experiments (proving that a quantum computer is quantum computing is something which many experimentalists have struggled over, for far smaller systems than D-wave’s system.) But there is a much simpler experiment which I haven’t seen answered in any of the press on D-wave, and which, for the life of me, I don’t understand why it hasn’t been done and publicized.
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D-Wave Talk

So did anyone at MIT go to this talk and care to comment:

Mohammad Amin (D-Wave)
Adiabatic Quantum Computation with Noisy Qubits
Adiabatic quantum computation (AQC) is an attractive model of quantum computation as it may naturally possess some degree of fault tolerance. Nonetheless, any practical quantum circuit is noisy and one must answer important questions regarding what level of noise can be tolerated. Gate model quantum computation relies on three important quantum resources: superposition, entanglement, and phase coherence. In this presentation, I will discuss the role of these three resources and the effect of environment upon them with respect to AQC. I will also show a close relation between open AQC and incoherent tunneling processes as in a double-well potential. At a more microscopic level, I will present a non-Markovian theory for macroscopic resonant tunneling, together with recent experimental results on superconducting flux qubits which demonstrate excellent agreement with the theory and may shed light on the microscopic origin of flux noise in these devices. Finally, I will discuss the effect of low and high frequency noise on practical AQC processors and compare AQC with thermal annealing.

Update (11/21/07): Geordie Rose has put the slides of the talk online at this blog post. I’ll have to look at them while eating Turkey.

Life-Size Quantum Computers

D-wave systems, whose paracomputer, err, I mean quantum-maybe computer, which sparked quite a bit of controversy earlier this year, is back in the news. This time D-wave is at the big superconducting conference (SC07) being held in Reno, Nevada and is demonstrating a 28-qubit quantum-maybe computer. Paint me an ivory tower skeptic, but I don’t think their system will work as they expect it to. Of course, this being, D-wave, the news article makes for some entertaining reading.
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The Purpose of This Blog

Oftentimes I’ve been asked what the purpose of this blog is. As if everything in life must have a purpose:pfft, I say! But because an answer is required, what I usually answer is that the purpose of my blog is to slow down my fellow researchers. I mean sheesh, the people in quantum computing are the modern polyglots of science, speaking physics, computer science, and mathematics with ease. And they’re universally a brainy crowd. So what better purpose can this blog serve that to slow these readers down by offering them great opportunities to surf the intertubes and procrastinate.
Along those lines…
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