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0 pointssanxiyn6y ago0 comments

This depends on your definition of "trivial". But if we restrict it to factoring, no, there is no known path to QC factoring at the moment, none at all.

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6 comments · 2 top-level

jessriedel6y ago· 4 in thread

I don't understand. Factoring composite numbers into their primes is definitely a predicted use for QC in the future. Are you just saying the architecture of the machine powerful enough to do that is still uncertain?

sanxiynOP6y ago

I think it is analogous to fusion. Fusion definitely works (the Sun and hydrogen bomb) and power generation is a predicted use of fusion in the future. That doesn't mean we have known path to fusion for power generation.

To extend the analogy, quantum supremacy is like fusion for neutron source. There are commercial fusion devices to be used as neutron source.

ac296y ago

> That doesn't mean we have known path to fusion for power generation.

Perhaps this was just a poor example, but we absolutely have a path to fusion power generation. ITER [0][2] is under construction now, and is expected to be capable of 10x power returns. DEMO [1] should have 25x.

[0] https://en.wikipedia.org/wiki/ITER

[1] https://en.wikipedia.org/wiki/DEMOnstration_Power_Station

[2] https://media4.s-nbcnews.com/j/newscms/2017_52/2273651/17122... (worth a click)

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jessriedel6y ago

Everything hinges on what you mean by the very vague term "known path". Every technology more than a few years out requires currently unknown problems to be solved. Even, say, the next generation of processors will require many engineer-years to solve currently unsolved problems, and the generation after that is pretty opaque right now. Still, we can have confidence that they will be developed.

empath756y ago

Right but in the foreseeable future we might be able to factor numbers as large as like 24. Not 24 digits. 24 the number.

cma6y ago

Factoring has already been done. For the size number factored it did use much more energy than it would have taken on a classical device, but it did utilize quantum effects/Shor’s algorithm:

https://en.m.wikipedia.org/wiki/Integer_factorization_record...

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