- Found a good news article at

http://www.nist.gov/public_affairs/releases/fourier.htm

part of which is below. The whole article goes into more detail

regarding how the quantum Fourier transform works.

Mark

May 12, 2005

Boulder, Colo.A crucial step in a procedure that could enable future

quantum computers to break today's most commonly used encryption

codes has been demonstrated by physicists at the U.S. Commerce

Department's National Institute of Standards and Technology (NIST).

As reported in the May 13 issue of the journal Science,* the NIST

team showed that it is possible to identify repeating patterns in

quantum information stored in ions (charged atoms). The NIST work

used three ions as quantum bits (qubits) to represent 1s or 0sor,

under the unusual rules of quantum physics, both 1 and 0 at the same

time. Scientists believe that much larger arrays of such ions could

process data in a powerful quantum computer. Previous demonstrations

of similar processes were performed with qubits made of molecules in

a liquid, a system that cannot be expanded to large numbers of qubits.

"Our demonstration is important, because it helps pave the way toward

building a large-scale quantum computer," says John Chiaverini, lead

author of the paper. "Our approach also requires fewer steps and is

more efficient than those demonstrated previously."

The NIST team used electromagnetically trapped beryllium ions as

qubits to demonstrate a quantum version of the "Fourier transform"

process, a widely used method for finding repeating patterns in data.

The quantum version is the crucial final step in Shor's algorithm, a

series of steps for finding the "prime factors" of large numbersthe

prime numbers that when multiplied together produce a given number.

Developed by Peter Shor of Bell Labs in 1994, the factoring algorithm

sparked burgeoning interest in quantum computing. Modern cryptography

techniques, which rely on the fact that even the fastest

supercomputers require very long times to factor large numbers, are

used to encode everything from military communications to bank

transactions. But a quantum computer using Shor's algorithm could

factor a number several hundred digits long in a reasonably short

time. This algorithm made code breaking the most important

application for quantum computing - hi,

Shoup presents us with a polynomial time factoring

algorithm using quantum computers. Its still not known

if such a powerful computer can be made but NIST's

announcement points out this may be possible. You may

be interested in looking at this.

http://arxiv.org/abs/quant-ph/0010034

Sarad.

--- Mark Underwood <mark.underwood@...>

wrote:> Found a good news article at

http://www.nist.gov/public_affairs/releases/fourier.htm

>

>

>

__________________________________

> part of which is below. The whole article goes into

> more detail

> regarding how the quantum Fourier transform works.

>

> Mark

>

>

>

Discover Yahoo!

Have fun online with music videos, cool games, IM and more. Check it out!

http://discover.yahoo.com/online.html - Its Shor and not Shoup.

My bad.

__________________________________

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