quantum computerA quantum computer is a machine, as-yethypothetical, that performs calculations based on the behavior of particles at the sub-atomic level. Such a computer will be, if it is ever developed, capable of executing far more millions of instructions per second ( MIPS ) than any previous computer. Such an exponential advance in processing capability would be due to the fact that the data units in a quantum computer, unlike those in a binary computer, can exist inmore than one state at a time. In a sense, the machine "thinks" several "thoughts" simultaneously, each "thought" being independent of theothers even though they all arise from the same set of particles. Engineers have coined the term qubit (pronounced KYEW-bit) to denote the fundamental data unit in a quantum computer. A qubit is essentially a bit (binary digit)that can take on several, or many, values simultaneously. The theory behind this isas bizarre as the theory of quantum mechanics, in which individual particlesappear to exist in multiple locations. One way to think of how a qubit can exist inmultiple states is to imagine it as having two or more aspects or dimensions, each ofwhich can be high (logic 1) or low (logic 0). Thus if a qubit has two aspects, itcan have four simultaneous, independent states (00, 01, 10, and 11); if it has threeaspects, there are eight possible states, binary 000 through 111, and so on. Quantum computers might prove especially useful inthe following applications: - Breaking ciphers
- Statistical analysis
- Factoring large numbers
- Solving problems in theoretical physics
- Solving optimization problems in many variables
The main difficulty that theresearch-and-development engineers have encountered is the fact that it is extremelydifficult to get particles to behave in the proper way for a significant length of time. The slightest disturbance will cause the machine to cease working in quantumfashion and revert to "single-thought" mode like a conventional computer. Stray electromagnetic fields, physicalmovement, or a tiny electrical discharge can disrupt the process.
|
| Read more about it at:
| |
|
|
| Last updated on:
Sep 21, 2005 |
|
Are you a Know-IT-All?
What was the first computer virus to spread in the wild?
Answer
|
|
|
|
|
