ABSTRACT
At the atomic level, we have new kinds of forces, new kinds of possibilities and new kinds of eects.
RICHARD FEYNMAN
4.1 INTRODUCTION On the subject of physics, Albert Einstein once said: “If you can’t explain it simply, you don’t understand it well enough. It should be possible to explain the laws of physics to a barmaid.” It is hoped that this chapter will be understood by barmaids, because the mathematics will be kept at a low level. We are reminded of a quote from Richard Feynman: “I love only nature, and I hate mathematics.” (Space and Motion). is chapter will mainly emphasize the physical concepts and their meaning.
