From: Dominic Ashfield 3/02/99 11:21:55 Subject: Quantum Computers post id: 120 Hello, my name is Dominic Ashfield. I was wondering where on the net to go for information on Quantum Computer development? This is a new kind of computer that is being developed. It will be much faster than the fastest computers today due to its use of electrons instead of "1's" and "0's". There are many different kinds of electrons and it is thought that if a computer can be fed these instead of ones and zeros it could complete calculations much faster. The reason for this is that instead of having a mere two digits that must be given to the computer in an almost morse code type fashion you can feed it any number of the different electrons, thus creating a computer alphabet. Having this alphabet is more useful because the computer does not have to convert and wait for enough morse to be pumped in to get the programmers command across. Any sites on this or information would be great. Thanks, Dominic Ashfield From: Dr. Ed G (Avatar) 3/02/99 12:38:09 Subject: re: Quantum Computers post id: 127 There is actually a bit more to quantum computing than using single electrons to store information. It is in fact truer to say that a quantum computer is any device that uses correlated quantum mechanical systems (which could be anything from an array of quantum dots defined on the surface of a semiconductor, to low temperature electron solids [mostly quite esoteric stuff]). Unfortunately, quantum computing is very much in its early infancy of development. It is mostly theoretical at this stage, and as I am aware, experimentally no-one has yet gone beyond a single solitary logic gate (in fact the only demonstration I've seen is of a NOT gate, a single input single output device which gives you a 0 if you input a 1, and 1 if you input a 0). Furthermore, it is only expected to be better than standard computers at doing things like searching large data sets, and cryptography, which is hugely important for big business and intelligence organisations such as the CIA, but not of much direct use for the rest of us. For more information the Centre for Quantum Computing can be found at http://www.qubit.org/ Soupie twist, Ed G. From: Chris (Avatar) 3/02/99 17:40:08 Subject: re: Quantum Computers post id: 155 Quantum processing… Quantum processing works on the many worlds interpretation of quantum theory, and also on parallel processing developed by Thinking Machines of Massachusetts in 1980. A simple model quantum processor might be an electron in an atom. We could let the ground or normal state of the electron be represented by 0 and the excited state by 1. This is referred to as a quantum dot (as mentioned by Dr Ed). Now we bombard the electron with photons sufficiently long enough so that a superposition of states occurs. In this sense the electron is both unexcited and excited at the same time until the state is resolved by observation, much the same as the famous Schroedinger's cat thought experiment. Only no observation is made! According to the many worlds interpretation there are now two "virtual electrons" in virtual parallel universes, one excited, one not excited. Extending this enormously, we might imagine thousands of electrons in separate "universes" working on a single problem, which is where the parallel processing comes in. Peter Shor of AT&T Bell Labs showed that this principle would in theory allow such a processor to work out complex problems in cryptography. Most "uncrackable" codes these days are based on multiplying extremely high prime numbers together to obtain even larger numbers. Shor showed that different electrons in parallel universes could guess at potential factors, the solution being shown as the constructive interference pattern of all states added together. The added bonus is that incorrect guesses disappear in destructive interference. The solution can be achieved very quickly, Shor showed that with the processing power of an early 1990s PC he could solve in minutes what a classical computing code cracker might take months or years to achieve. As Ed says, however, the practical everyday applications are at this stage somewhat limited, and little actual production has been developed. Hope this helps! Chris This forum is un-moderated. The views and opinions expressed are those of the individual poster and not the ABC. The ABC reserves the right to remove offensive or inappropriate messages.