# Quantam supremacy?



## Splinterdog (Oct 31, 2019)

This has to be a good thing for the world, surely?
*What Is Quantum Supremacy?*


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## notb (Oct 31, 2019)

There are better places to ask this question, surely.









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## Boatvan (Oct 31, 2019)

"Quantum Supremacy" would make a great band name


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## Vya Domus (Oct 31, 2019)

Not really, "quantum supremacy" just means a quantum computer did something that couldn't be feasibly simulated with a classical computer, meaning it would take too much time or memory.

Now whether or not that "something" was actually useful is not required. Most of the research proved quantum computers can do "something" but the matter of the fact is they are still struggling to write useful software among other things.


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## R-T-B (Oct 31, 2019)

This may be an "opinion" piece, but it's still a way way better explanation than that tabloid-esque link:









						Opinion | Why Google’s Quantum Supremacy Milestone Matters (Published 2019)
					

The company says its quantum computer can complete a calculation much faster than a supercomputer. What does that mean?




					www.nytimes.com


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## DeathtoGnomes (Oct 31, 2019)

Vya Domus said:


> Not really, "quantum supremacy" just means a quantum computer did something that couldn't be feasibly simulated with a classical computer, meaning it would take too much time or memory.
> 
> Now whether or not that "something" was actually useful is not required. Most of the research proved quantum computers can do "something" but the matter of the fact is they are still struggling to write useful software among other things.


I am quantum computer cuz i can do something while any software updates still struggle to be useful.  

OH and I have supremacy over my domain, please leave your shoes at the door.


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## thesmokingman (Oct 31, 2019)

That made Jim Keller lol... keep remembering him shake his head at QC.


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## notb (Oct 31, 2019)

Vya Domus said:


> Now whether or not that "something" was actually useful is not required. Most of the research proved quantum computers can do "something" but the matter of the fact is they are still struggling to write useful software among other things.


Well, that's the case more or less. It means there's a PoC that quantum computers can do what they've been designed to do: solve problems that normal computers won't be able to for a long time (or ever).
It's a lot like an experiment confirming a theory that everyone believes to be true.

As for "usefulness": IMO some people still don't understand what quantum computing is about and this results in unrealistic expectations.

Quantum computers won't replace what we have today. We won't use them at home and it's even unlikely we will use them remotely on servers for "consumer tasks".

Moreover, solving problems that can't be solved is a nice marketing exercise (and will have some actual meaning in science), but that's not why Google or IBM invest in developing quantum computers.
There are problems in science and engineering that currently take many hours or days to be solved using supercomputers/clusters.
A quantum computer will provide the same answer in seconds.
And that's just faster and (likely) cheaper.
That's it.


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## R-T-B (Oct 31, 2019)

thesmokingman said:


> That made Jim Keller lol... keep remembering him shake his head at QC.



You say that like it's not a prophecy destined for failure.



notb said:


> That's it.



Pretty much spot on.  The biggest hurdle from them comes when they are cheaply accessible and can break existing conventional encryption...  fortunately, we are already working on some answers to that (referered to as "Quantum Hardening").


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## JohnSimpson (Dec 6, 2019)

As for me, it is the most interesting area in the Physics at all. Time Leaps, Traveling and other aspects were mysterious for all the people every time.


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## notb (Dec 6, 2019)

JohnSimpson said:


> As for me, it is the most interesting area in the Physics at all. Time Leaps, Traveling and other aspects were mysterious for all the people every time.


Sorry to bring bad news, but quantum physics is not about time travel and other stuff you've seen in movies.

It's about: hey look it's a dog shit - why does it exist at all and not decompose into free flying atoms?
Or: hey look, we've put a single photon in a tiny box. Lets make it glow green!
Or: hey, we've found a new model for dark matter and it's so cute!

Yeah, but really, QM (and all its sick children: quantum field theory, quantum electrodynamics...) is about understanding the stuff that's around us. Because most of the time we don't understand the phenomena that we observe.
And quantum computers will help for sure, but honestly, 90% of the time they'll just do complex cryptography...

The stuff that we don't observe (like time travel...) is not that interesting for physics - actually for science in general.


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## Vayra86 (Dec 6, 2019)

notb said:


> Moreover, solving problems that can't be solved is a nice marketing exercise (and will have some actual meaning in science), but that's not why Google or IBM invest in developing quantum computers.
> There are problems in science and engineering that currently take many hours or days to be solved using supercomputers/clusters.



You do glance over an important type of workload or task there: time critical ones. Encryption is one of those; the whole reason it works is because with normal computers it takes way too long to figure it out.

Its not about money, and that is why they call this 'supremacy'. Its not really a performance difference, but a difference in approach, which is a gap you'd never be able to cross with just 'more performance', because it would not be feasible and eliminates the purpose of doing it.


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## xtreemchaos (Dec 6, 2019)

it time to ask the age old question "can a Quantum computers run Crysis"   "sorry I couldn't help myself" thay proberly could and could not all at the same time if we could get one to work long enough..


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## DeathtoGnomes (Dec 7, 2019)

notb said:


> Sorry to bring bad news, but quantum physics is not about time travel and other stuff you've seen in movies.
> 
> It's about: hey look it's a dog shit - why does it exist at all and not decompose into free flying atoms?
> Or: hey look, we've put a single photon in a tiny box. Lets make it glow green!
> ...


Its that understanding of QM on how things work that puts the 'R' into the R&D of time travel, or, we can just wait for the the day and have the Vulcans just give us the technology for time travel.


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