You can't access the results individually, and that's the catch. QC does not lead to an exponential speed-up because, even though the "model" says every computation is performed simultaneously, you can only access ONE of the result. As soon as you read one result all the others "collapse" to that result.
Imagine a 256 pages book containing the square root of the first 256 integers. Then the only thing you can do is randomly open the book to any page. Say you get sqrt(4)=2. Then every other page of the book holds a 2.
You can still use QC to an advantage, but you have to be tricky: waiting as long as possible to read the output and making "interference" operations to increase the probability of the desired answer to show up. That is how a QC can theoretically search an unsorted array in a time proportional to SQRT(n).
But you will get a crappy digital copy of your movie, its quantum state will be lost forever. Movies of the future are going to be so quantum. Anybody with a crappy digital HDTV will be such a looser!
This is plain wrong. It is known that the class of problems solvable in linear time on a quantum computer is included in NP, and it is believed that this is a strict inclusion. That means there does not exist an NP-complete problem for which a linear-time quantum algorithm is known. Most researcher also believes that we will not find such an algorithm.
That doesn't mean Quantum computers are useless, though. There exists problems in NP for which no classical linear-time algorithm is known and for which we found a linear-time quantum algorithm.
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You can't access the results individually, and that's the catch. QC does not lead to an exponential speed-up because, even though the "model" says every computation is performed simultaneously, you can only access ONE of the result. As soon as you read one result all the others "collapse" to that result. Imagine a 256 pages book containing the square root of the first 256 integers. Then the only thing you can do is randomly open the book to any page. Say you get sqrt(4)=2. Then every other page of the book holds a 2. You can still use QC to an advantage, but you have to be tricky: waiting as long as possible to read the output and making "interference" operations to increase the probability of the desired answer to show up. That is how a QC can theoretically search an unsorted array in a time proportional to SQRT(n).
But you will get a crappy digital copy of your movie, its quantum state will be lost forever. Movies of the future are going to be so quantum. Anybody with a crappy digital HDTV will be such a looser!
This is plain wrong. It is known that the class of problems solvable in linear time on a quantum computer is included in NP, and it is believed that this is a strict inclusion. That means there does not exist an NP-complete problem for which a linear-time quantum algorithm is known. Most researcher also believes that we will not find such an algorithm. That doesn't mean Quantum computers are useless, though. There exists problems in NP for which no classical linear-time algorithm is known and for which we found a linear-time quantum algorithm.
Real estate values in the Canadian great north up 25% while Florida retirement homes file for bankrupcy.
This is how the Montreal Keno Cheater was caught in 1994. http://en.wikipedia.org/wiki/Montreal_Casino
Maybe we're not thinking of the same Linsey Lohan, but the one I know fails to show the desired vertical and horizontal lines.