Robotics Reference
In-Depth Information
switch at the rate of ten billion times per second). Researchers at the
University of Rochester believe that their work could lead to a computer
more than a billion times faster than the supercomputers at the start of
the twenty-first century. The plethora of state-of-the-art research estab-
lishments that are investigating optical computing presages an exponen-
tial growth in this particular area of computing technology.
The DNA Computer
In 1994, Leonard Adelman
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introduced the idea of using DNA to solve
complex mathematical problems. DNA (or, to give it its full name, De-
oxyriboNucleic Acid) is the material our genes are made of—molecules
that carry huge amounts of genetic information. This information is
necessary for the organization and functioning of most living cells and
controls the way that characteristics are inherited from one generation
to the next. Adelman came to the conclusion that DNA is very sim-
ilar to a computer's disk drive in how it stores permanent information
about our genes. And he realized that DNA can not only carry huge
amounts of information, it can also process huge amounts of informa-
tion and therefore has the potential to perform calculations many times
faster than the world's most powerful man-made computers. Adelman's
article in a 1994 issue of the journal
Science
outlined how to use DNA
to solve a well-known mathematical problem known as the Travelling
Salesman problem at a phenomenal speed. The goal of the problem is
to find the shortest route a salesman can take, visiting each of a num-
ber of cities once and only once. As more cities are added, the problem
becomes much more difficult and more time consuming to solve. The
beauty of DNA computing is that it allows the examination of all possi-
ble solutions to a problem in parallel. The difficulty with problems such
as the Travelling Salesman is that the optimal solution must satisfy several
different conditions simultaneously, so every aspect of a possible solution
must be verified. Performing all the verification tasks at once speeds up
the solution process dramatically.
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Prior to 1994 Adelman, a computer scientist at the University of Southern California, was best
known for his role in devising the RSA encryption algorithm, the most powerful method known for
encrypting confidential information to keep it from prying eyes. (The other inventors of RSA were
Ron Rivest and Adi Shamir.)
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Just three years after Adelman's original experiment, researchers at the University of Rochester
developed logic gates made of DNA.
