Abstract - Quantum Computers are widely acclaimed as the future computers. There is so much research being done in this field of Quantum Computers that one would rightly feel that the advent of Quantum Computers for everyday use is not far off. But at a time when Global Warming has become a real threat to our very existence, the question we need to responsibly ask ourselves before take on this new invention is whether it will in any way ruin our existence. This paper evaluates the two main approaches to Quantum Computer Systems that are being researched at present from the light of the Green Computing approach. The central thrust of this paper is to avoid a technological advancement that could cause more harm than good in the future. Keywords-Green Computin, Photonics; Spintronics; Quantum Computers
―For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.‖ —Richard P. Feynman (1986) There is nothing more real than the fact that humanity today is heading towards total annihilation if we do not do something to stop Global Warming. Steps have been taken constantly by Governments and public at large to reduce the rate of the Global Warming process and Green Computing is one major step in this direction considering the fact that computers are one big source of the warming process. But this initiative can only extend life by a few more years. The real cure lies in drying up the source rather than slowing it down. The twentieth century has, no doubt, been the century of computers. Beginning with machines as big as a building, we have reached sizes below which it would be too inconvenient to handle. But just as everything comes to end, Gordon Moore’s law on the shrinking of computer chip is also nearing its end. The twenty-first century has something different in store. Just as over the time, the rules of classical physics are being replaced by Quantum Mechanics in the building of
computers. And when this happens, the computers on our desks will be replaced by systems that work on an entirely different principle. That day is not very far off. While a lot of effort and money is being utilised in ensuring that this happens at the earliest, one basic reality that should be kept in mind is the reality of Global Warming. If the replacing computers still keep producing heat, we have not achieved much in the sense of drying up the source of Global Warming caused by the use of computers. Whether or not heat produced can be totally stopped will be a matter of debate in thermodynamics but to what extended can it be made insignificant to global warming depends on how we advance in the technology of Quantum Computers. The first part of the paper establishes the problem in our present technology. Here the various problems in the classical computer are presented in the light of Green computing. The second part introduces the Quantum Computing technology that is bound to replace the present technology in the near future. The third and fourth part of the paper deals with two different architectures that are commonly researched for use in Quantum Computers. Due to limitations of this paper, these architectures are not dealt with in detail. Only their advantages and disadvantages are discussed. II. GREEN COMPUTING
Green Computing has been the effort in the direction of using computer resources more efficiently without causing much harm to the environment. While on one hand, the need for reducing the harm being done is acknowledged, Green Computing is also an acknowledgement that the present technology is defective by its very nature. Some of the major drawbacks of this technology are : A. Scalability limitation
Classical computer chips are limited in their ability to increase in density and speed. The size of a computer’s chip had been...