What is Molecular Computing ?

hello friends,

I want to know what is the concept of molecular computing ? Can anybody provide me the detailed information about this concept ?

thanks...

Molecular computing

Molecular computing is a generic term for any computational scheme which uses individual atoms or molecules as a means of solving computational problems.
Molecular computing is most frequently associated with DNA computing, because that has made the most progress, but it can also refer to quantum computing or molecular logic gates.
All forms of molecular computing are currently in their infancy, but in the long run are likely to replace traditional silicon computers, which suffer barriers to higher levels of performance.

Molecular computers are massively parallel computers taking advantage of the computational power of molecules (specifically biological).

Molectronics specifically refers to the sub-field of physics which addresses the computational potential of atomic arrangements.

Different proposals for molecular computers vary in the principles of their operation.

In DNA computing, DNA serves as the software whereas enzymes serve as the hardware. Custom-synthesized DNA strands are combined with enzymes in a test tube, and depending on the length of the resulting output strand, a solution can be derived. DNA computation is extremely powerful in its potential, but suffers from major drawbacks. DNA computation is non-universal, meaning that there are problems it cannot, even in principle, solve. It can only return yes-or-no answers to computational problems. In 2002, researchers in Israel created a DNA computer which could perform 330 trillion operations per second, more than 100,000 times faster than the speed of the fastest PC at the time.

Another proposal for molecular computing is quantum computing. Quantum computing takes advantage of quantum effects to perform computation, and the details are complicated. Quantum computing depends upon supercooled atoms locked in entangled states with one another. A major challenge is that as the number of computational elements (qubits) increases, it becomes progressively more difficult to insulate the quantum computer from matter on the outside, causing it to decohere, eliminating quantum effects and restoring the computer to a classical state. This ruins the calculation. Quantum computing may yet be developed into practical applications, but many physicists and computer scientists remain skeptical.

Advantage of Molecular Computing -
How does molecular computing can make a difference -

A single kilogram of carbon contains 5 x 10(raise to 25) atoms. Imagine if we could use only 100 atoms to store a single bit or perform a computational operation.
Using massive parallelism, a molecular computing weighing just a kilogram could process more than 10(raise to 27) operations per second, more than a billion times faster than today’s best supercomputer, which operates at about 10(raise to 17) operations per second. With so much greater computational power, we could achieve feats of calculation and simulation unimaginable to us today.