The Potential of Quantum Computers

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Quantum computing, a thing most people have never heard of, is becoming a reality. In a traditional computer, information is represented by a sequence of bits representing either 0 or 1 and are managed by logic gates. In a quantum computer, information is represented by qubits and is handled by quantum gates. A quantum computer uses the strange quantum mechanic laws to process this information in a new way. Each qubit can be in many different states represented by a vector based on its spin and direction. A qubit can be either in the position 0 or 1, or in any position between them, representing 0 and 1 at the same time. This may seem strange, but it obeys the quantum mechanic laws. The state of each qubit can be changed by a pulse of a wave, and can change just one qubit, or up to every qubit in the system. For example, our computers now have 2⁶⁴ different states on a 64 bit machine. In a quantum computer we could change all 2⁶⁴ states in one clock cycle with a pulse of a wave, exponentially faster than we can on a regular computer, and even faster than a supercomputer.
 Peter Shor, a graduate of Berkeley and current faculty member at MIT, developed the algorithm known as "Shor's algorithm". This algorithm, given an integer, finds it's prime factors on a quantum computer. Because it is on a quantum computer, it is much faster than the most efficient known traditional factoring algorithm. While current technology has limited testing this algorithm to only finding the factor of 21, hopefully soon a quantum computer will be built and could be used to break almost any cryptography keys that are based on factoring large numbers.

-Mark Stumpf

References
http://www.cs.rice.edu/~taha/teaching/05F/210/news/2005_09_16.htm
http://yaledailynews.com/blog/2013/01/29/physicists-observe-quantum-computing/
http://en.wikipedia.org/wiki/Peter_Shor