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Getting the World Quantum Ready

36 points| zaphod_ibm | 8 years ago |ibm.com | reply

13 comments

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[+] ivansavz|8 years ago|reply
> What if everyone in the 1960s had a decade to prepare for PCs [...] while they were still prototypes? In hindsight, we can all see that jumping in early would have been the right call.

This is an interesting hypothetical based on the assumption that quantum computers will be available in 10 years time. What if the first practical quantum computers are still 50 years away? Using the same hypothetical, it would be like someone preparing for the PC age in that 1920s. That might be "jumping in" too early.

[+] extide|8 years ago|reply
Am I missing something because D-Wave has 1024 qubit machines available now and 2000 qubit ones soon.
[+] archgoon|8 years ago|reply
I'm going to repost from a year ago:

D-Wave isn't trying to build a general purpose quantum computer. As it stands, they've been trying to optimize a computer that executes a particular algorithm (and as it stands, it's not faster than optimized classical algorithms). It is an open research question if D-Wave's architecture actually utilizes any quantum effects to give it an advantage over classical architectures. D-Wave hopes that it does, and that there will be enough problems that their machine is good at that their approach will be justified.

D-Wave markets themselves as having hundreds or thousands of qubits, but these qubits aren't easily controllable or measurable in ways that would allow Shor's Algorithm to be executed on them (for example), so at the least, it seems like dishonest marketing. In order to build a general quantum computer, you need to be able to apply gates to arbitrary collections of qubits.

[+] benchaney|8 years ago|reply
D-Wave isn't a real quantum computer in the way that most people use the term, so that isn't an apples to apples comparison.
[+] omarforgotpwd|8 years ago|reply
Can I run Shors algorithm on this? If not, how many qubits would I need for that? If so, how do I short bitcoin?
[+] archgoon|8 years ago|reply
According to this paper:

https://arxiv.org/abs/quant-ph/0205095

You can implement Shor's algorithm to factor an N-bit number with just 2n+3 qubits. So the 20 qubit processor would be able to factor any 8 bit number (not necessarily faster than a classical computer could, or even a human could, mind you).