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Quantum information is the physics of knowledge. To be more \n To date, the two most promising uses for such a device are
\n specific, the field of quantum information studies the implications that quantum
\n mechanics has on the fundamental nature of information.
\n By studying this relationship between quantum theory and information,
\n it is possible to design a new type of
\n computer—a quantum computer<\/em>.
\n A largescale,
\n working quantum computer—the kind of quantum computer some
\n scientists think we might see in 50 years—would be capable
\n of performing some tasks impossibly quickly.\n<\/p>\n
\n quantum search<\/a> and
\n quantum factoring<\/a>.
\n To understand the power of a quantum
\n search, consider classically searching a phonebook for the name
\n which matches an unknown phone number.
\n If the phonebook has 10,000
\n entries, on average you’ll need to look through about half of
\n them—5,000 entries—before you get lucky. A quantum
\n search algorithm only needs to guess 100 times. With 5,000 guesses
\n a quantum computer could search through a phonebook with 25 million names.\n<\/p>\n
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