21st Century Physics
an Online Book
by
Isaac M. Gray, III

Copyright 1999 Physics Concepts - All rights reserved.

Part I - Of Past Model Structures
Introduction

We observe the universe around us and might marvel at the structure of it. Become inspired by it's complexities, its harmony, simplicity and chaos. Is the universe all of these things at once? Or is it none of the above? Does it all depend on our point of view? Or is there really an inherent structure deep below everything that we see with our natural senses? Is there something that binds it all together? These are questions that students have asked at least since the ancient Egyptian and Greek civilizations. But our purpose is not to get philosophical in the disciplined sense of the word. Our curiosity simply begins with the question, "How does it all work?" "It" being the universe, then moves on to "Why does it work the way it does?" Occasionally or quite often we might ask the question, "What made it work? Or WHO made it work?"

The last two questions we will leave outside the scope of these volumes and instead will focus on How does it all work? and Why does it work the way it does? From the earliest times of pre-recorded history, when intelligent life came about on our earth the questions have streamed forth. They continue now as we press on for answers. The units used in this book are in SI units and our answers will be calculated to three significant figures unless otherwise specified.

Also, most of the mathematical formulas are embedded in the html script and use the new xml standard under development by the W3C Consortium. Your browser may ask if you want the EZmath plug-in. Simply click to download the plug-in. This is a rather new development (last 2 years) to standardize the mathematical operators within the html environment, and a welcomed one at that. Directions for the plug-in can be found under Physics News on the homepage.

Embedded in the text is a little symbol, . When a calculation may need to be performed, there is a physics computer for calculations on the web - which is linked to a Java Script "Pocket Physics Computer". For its use, I would like to thank the Department de Physique Facultés Universitaires Notre-Dame de la Paix de Namur, used with the permission of Jean-Pol Vigneron. A special thanks to The Royal Swedish Academy of Sciences for their permission to use a graphic covering, Leptons, Quarks and Force Carriers. Thanks to Eva Krutmeijer for all her help. To Jonathan Bower, thanks for your tireless hours rendering graphics to pictorially capture physical concepts.