quantum computer

computer A type of computer which uses the ability of

quantum systems, such as a collection of atoms, to be in many

different states at once. In theory, such superpositions

allow the computer to perform many different computations

simultaneously. This capability is combined with interference

among the states to produce answers to some problems, such as

factoring integers, much more rapidly than is possible with

conventional computers. In practice, such machines have not

yet been built due to their extreme sensitivity to noise.

Oxford University ,

Stanford University .

A quantum search algorithm for

constraint satisfaction problems exhibits the phase

transition for NP-complete problems.

(1997-02-11)