I kinda got my answers after GOOGLING A BIT! and asking a few diffrent ppl
I can't explain quantum physics to you here, just the general concept of "why quantum computers are so great".
A current computer can evaluate a function, say, calculate whether a number can be divided by 3. However, if you want to know which ones of the first 10100 numbers can be divided by 3, you've got to do the calculation 10100 times.
The quantum computer does the calculation once, and yields all possible results all at the same time.
Quantum computers won't take over the computer world as they have a very specific type of operation, namely calculating the same thing with a lot of different parameters very quickly; there is no real reason to use quantum computing for single calculations. However, combined with a normal computer it can solve difficult problems in very small times. Probably the most important application is factorization of large numbers, which is heavily used in modern cryptography.
To my awareness, there are only 3 algorithms known for quantum computing:
1. The Deutsch algorithm, which checks whether a function is constant. This one is pretty useless in practice, but serves well for educational purposes.
2. Searching a database (in theory)
3. Factoring numbers (they factorized 15)
As you can see, there's still a lot of work to do, factoring 15 isn't that much of a possible application yet
A binary register with N bits in the quantum computer can be in all the 2^N different states at the same time due to quantum magic.
You still need to let the different states interfere with each to get an output, so it DOES NOT automatically solve NP-complete problems.
O I DONT UNDERSTAND THIS QUANTUM MAGIC!!!!
-JETAMAY ASK YOUR BROTHER...
Last edited by Gourav2122; 02-22-2010 at 10:15 PM.