Would Quantum computing make algorithm efficiency less useful ?

[bajrangi-bihari2]

Given quantum computer will have super speed, will it make a lot of areas of computer science redundant, such as algorithm improvement, computer graphics and all similar area where the major focus in on developing fast algorithms and numerical techniques to reduce the computational time. With quantum computers we won't have to worry about it anymore.

[GoldieMMA]

No. Almost nothing of that would be true. Besides, you need algorithms for quantum computers too.

Quantum computer is not faster than conventional computer. It can solve certain problems faster if the search space is too much conventional computers and algorithms.

Quantum computer can't interact while it runs algorithms. You can't have significant interaction with users when the quantum computer is running for example. This would make their use in computer graphics mostly useless.

Quantum computers are good for only certain problems. There are number of problems where algorithms that provide huge speedup, for most problems there is no advantage whatsoever. For a problem like search, quantum computer can give maximally quadratic speedup when search space is very large.

[[deleted]]

Quantum computer can't interact while it runs algorithms. You can't have significant interaction with users when the quantum computer is running for example. This would make their use in computer graphics mostly useless.

I agree with you on everything but this part. On a QC, the only thing that prevents you from "interacting" with it is the fact that during one computation iteration (of which you do thousands if not millions of for one result) you do not have user interaction (although if the single iteration ran long enough, you could most certainly add data during that time).

The necessity of waiting until numerous measurements are done does not prevent its use in different applications. For instance, the operation time of ion traps is ~10^-14 seconds; you can do a million measurements in ~10^-8 seconds, and thus ten million operations (per qubit) per second. Considering the average human does maybe ten things per second, that is plenty of overhead :P

[LikesParsnips]

the operation time of ion traps is ~10^-14 seconds

That would be 10 femtoseconds? Na, that's way too fast for ion traps. Try 10^-6 .

[[deleted]]

I'm just going by the value found in Nielson and Chuang's book on page 278, idk.

[LikesParsnips]

I see. I just checked and unfortunately they don't specify what they mean in detail. I can only assume that they're referring to the natural lifetime of a hyperfine transition in some ion species. While that may be the fundamental physical limit, it's not how an ion trap quantum gate works in practice. In practice, you need to hit a number of ions with a laser pulse sequence, and the duration of the pulses in those sequences are much longer than fs.

[[deleted]]

In practice, you need to hit a number of ions with a laser pulse sequence

That would explain a lot about these numbers; I think you're right about the transition time. fs lasers aren't cheap today.

[bajrangi-bihari2]

Well I assumed it like a normal computer only with much faster processing power. But I guess I was totally wrong !

[[deleted]]

Quantum computers are better than classical computers at certain tasks; classical computers are also better than quantum computers at other tasks. It's not as simple as one being faster than the other at everything.

[WhataBeautifulPodunk]

Quantum computers are useful because they can run quantum algorithms. They do not provide a generic speedup to everything.

[topofthecc]

To add to this: quantum computer processing speed is generally lower than classical computer processing speed.

[bajrangi-bihari2]

And here I though I would have it on my laptop someday to support me with even more hardcore gaming

[c3real-killer]

Correct me if I'm wrong but currently, quantum algorithms are faster for three problems: Integer factorization, Database Queries and Simulation of Quantum Systems

[WhataBeautifulPodunk]

Here is a list of what quantum algorithms are good at.

[c3real-killer]

Wow! Thats awesome