Karma for Kovidgoyal

[Bilbo1967]

Originally Posted by kovidgoyal

Only PDF I'm afraid The quantum is referring to quantum mechanics. i.e. a computer driven by the laws of quantum rather than classical physics. Turns out to be significantly more powerful. For example, using a classical computer to search through a collection of N unsorted entries,will take, on average N/2 queries, whereas with a quantum computer it can be done in the square root of N. For very large N this can be a huge speedup.

Coincidentally, I read this on the BBC web site earlier this week.

I am certain that I don't really understand this area, but it is definately interesting.

[kovidgoyal]

Originally Posted by pshrynk

There's a story in there somewhere...

There have been quite a few SF books that try to use quantum computers, not very successfully though

[badgoodDeb]

Originally Posted by dogsballs

yes karma to Kovidgoyal i use calibre the only worry i have is his avatar it scares me

Funny -- I keep noticing how cute he is!! (but he's got a GF already )

Originally Posted by kovidgoyal

There have been quite a few SF books that try to use quantum computers, not very successfully though

So a quantum computer is only theory, or perhaps laboratory, so far?

Any relation to the ferro-electric materials mentioned in this article? (Art, in second paragraph, is my brother!)

[desertgrandma]

Look........only 218 karma points until Kovid breaks 30,000.......

C'mon people, give him a hand over!

[nekokami]

Originally Posted by kovidgoyal

Only PDF I'm afraid The quantum is referring to quantum mechanics. i.e. a computer driven by the laws of quantum rather than classical physics. Turns out to be significantly more powerful. For example, using a classical computer to search through a collection of N unsorted entries,will take, on average N/2 queries, whereas with a quantum computer it can be done in the square root of N. For very large N this can be a huge speedup.

I get the general idea (I was a physics major for 2 years with an interest in quantum mechanics), but I still haven't worked out how using quantum effects is faster. Is it faster for all sorts of calculations, or for specific tasks such as factoring (as mentioned in the BBC article above)? I know you mentioned search, which is so common that by itself it would be a help, even if regular silicon ICs were faster for other stuff. But I suspect there are broader applications. The only thing that seems analogous to me so far is that if the photons can be in multiple places at once, maybe you can do parallel processing that way?

[Harmon]

I don't know about you, but I've given him karma. That's spelled m-o-n-e-y.

You can, too!

[kennyc]

Originally Posted by Harmon

I don't know about you, but I've given him karma. That's spelled m-o-n-e-y.

You can, too!

Yep, I'm about to do that myself.

As far as I can tell calibre is the best out there.

[Wetdogeared]

Originally Posted by desertgrandma

Look........only 218 karma points until Kovid breaks 30,000.......

C'mon people, give him a hand over!

Done!

[desertgrandma]

Originally Posted by Wetdogeared

Done!

Karma to you for doing it!

I hope Kovid, you continue to get Karma, both numerically and financially, you deserve.

[kovidgoyal]

Originally Posted by badgoodDeb

Funny -- I keep noticing how cute he is!! (but he's got a GF already )

Actually, a wife, but thanks

So a quantum computer is only theory, or perhaps laboratory, so far?

Any relation to the ferro-electric materials mentioned in this article? (Art, in second paragraph, is my brother!)

There have been a few lab demos of quantum computers, but nothing of practical interest so far. My thesis actually presents a proposal for a design of a quantum computer that would actually be practical (i.e. be able to handle real world amounts of data). But a real working QC is still several years off.

And no, it's no relation to the article you quoted

[kovidgoyal]

Originally Posted by nekokami

I get the general idea (I was a physics major for 2 years with an interest in quantum mechanics), but I still haven't worked out how using quantum effects is faster. Is it faster for all sorts of calculations, or for specific tasks such as factoring (as mentioned in the BBC article above)? I know you mentioned search, which is so common that by itself it would be a help, even if regular silicon ICs were faster for other stuff. But I suspect there are broader applications. The only thing that seems analogous to me so far is that if the photons can be in multiple places at once, maybe you can do parallel processing that way?

Actually no one knows quote what makes quantum computers faster. Superposition (the mathematical name for a photon being in multiple places) definitely plays a role, as does entanglement (which allows for stronger correlations between systems than is possible in classical physics). In fact what makes quantum computers faster and just how much faster is very much an open question.

So far people have only found a handful of algorithms, factoring and search being the two most useful examples where quantum computers show a definite speedup over their classical cousins. In fact, in the case of catoring the speedup is actually exponential!

[pdurrant]

Originally Posted by kovidgoyal

[...] in the case of factoring the speedup is actually exponential [...]

... which will render all current public key encryption systems useless.

(As the public key is the product of two very large prime numbers. If you can factor the public key back into the two original prime numbers, you have obtained the private key, and the encryption is no longer useful.)

[kovidgoyal]

Originally Posted by pdurrant

... which will render all current public key encryption systems useless.

(As the public key is the product of two very large prime numbers. If you can factor the public key back into the two original prime numbers, you have obtained the private key, and the encryption is no longer useful.)

Yeah, it will

[kennyc]

Originally Posted by kovidgoyal

Yeah, it will

Ah I see, your an anarchist.

[kovidgoyal]

Originally Posted by kennyc

Ah I see, your an anarchist.

Actually quantum communication (specifically using entangled states) provides far more secure forms of authentication that large prime numbers. Hence the "communication" in my thesis title.