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Physics Utilizing Computer Technology or Computer Technology Utilizing Physics? (Part 2)

by Clarissa Lee for hackinthebox.org

This being the holiday season, I felt incline to just laze about and read all the old stories that I’d not touched in a long while just to reminisce about the past. But as I’d promised in the previous installation that I would be back to initiate you into the worlds of computer physics, it will be done.

In the previous installation, we were talking about how computer technology has been one of the backbones for quantum leap (pun intended) in physics. Neither would computers have gotten very far without the discoveries made which helped in its evolution. Incidentally, this year’s Nobel Prize for physics had been awarded to three men that had help to break the boundaries of computing technology more than 30 years ago, ZHORES I. ALFEROV, and HERBERT KROEMER for developing semiconductor heterostructures used in high-speed and opto-electronics, such technologies that had developed the radio-link satellites and mobile phones, even the now ubiquitous bar-code readers and your CD players. The other half of the Nobel Prize was awarded to JACK ST. CLAIR KILBY for his part in the invention of the integrated circuit that revolutionized personal computing and allowed computers to pass megabits of information through and fro in the computer’s IO system at a speed that you are used to now. If you are interested, you can read more about the background history at http://nobel.sdsc.edu/announcement/2000/phyen.html

Since we’d touched on the subject of semiconductors, and I’m sure most of you already know what it means, but just to give you the details subject itself would require more than one article. Basically, it’s semi-metallic crystals that have been doped with impurities, which create excesses of holes, that being the positive charge and electrons, the negative charge. It’s the manipulation of the molecular structure of the semiconductors that is the basis of the innovation made with semiconductors and where we get things from transformers, transistors, integrated circuits and opto-electronic devices. To truly understand the principles of semiconductors is not to merely study it’s electronic history but to understand the statistical mechanical workings of the system. In future installations, I will touch a bit on what I know about stastistical physics and give you references from the experts to look up. In the meantime, you might like to try out this cute site http://britneyspears.ac/basics.htm . Believe it or not, it does give you the fundamentals of semiconductors.

What is superconductivity? In other words, it’s conductivity at zero resistance and with 100% efficiency. When metal is cooled below a sharply defined temperature of T, of which depends on the external magnetic field H where the metal is located, the direct current electrical resistance of the metal falls abruptly to zero. Meanwhile, the current are set-up in the metal in such a way so that the magnetic induction B vanishes inside the metal (B=0) irrespective of the applied field H. Therefore, the superconducting state of the metal continues as long as the temperature is sufficiently low and the applied field is sufficiently small. Even though superconductivity was discovered in 1911 by Kammerlingh Onnes, it was only in 1957 that a successful microscopic theory of this phenomena was finally proposed. There’s a quantum-mechanical correlated motion of very many particles obeying Fermi-Dirac statistics in the microscopic theory.

Quantum computing came about with the application of Feynman’s probabilistic theory that incorporates the classical channel of communication utilizing Bayesian probability and Laplace’s rule of insufficient reason. To grasp what quantum computing can do, one must first grasp the workings of the Uncertainty principle and quantum entanglement that I will devote an article on before giving you the more technical references. There’s still another story on quantum teleportation (and it has nothing to do with Star Trek) but has a lot to do how information might be transported over the Internet not in one bit but in ebit (don’t you wonder?). I will not be going straight into what quantum computing can do for us now or in the future or its function but will begin with the foundations that led to its development. For the time being, do read up for some idea on it at http://www.sciam.com/explorations/091696explorations.html.

The development of lasers has also been instrumental in providing cutting-edge way of reading and writing information on to optical storage devices like CDs and in providing fibre optics link like the one we are having in Cyberjaya. As I’d already touched on holography that is related to lasers, I will not go into the details here. For those with no prior knowledge as to what lasers is, I’ll recommend going to http://members.aol.com/WSRNet/tut/ut1.htm to find out more.

In the next installation, I will be going into depth on each of the topics that I’d mentioned in this two-part article. After that, I will go on to topics in physics that might not have direct link with computing yet is important to its development. Then I might touch a little on the mathematics that is utilized in physics and computing. Until then, have a Happy New Year!

Copyrighted to Clarissa Lee, November 2000. First published in http://www.hackinthebox.org HITB issue 12