Physics Bootcamp

Welcome to physics! The laws of physics summarize our current understanding of the nature, from subatomic particles to the entire universe. The physics of large structures such as the image of the oldest recorded supernova RW86 observed by Chinese in 185 A.D. and seen in the sky as a bright star for eight month, shown in Fig. Figure 1.1 are, of course, very fascinating. So are the hexagonal carbon ring structures clearly visible in electron micrographs in Fig. Figure 1.2.

Over the past several centuries physicists have discovered some laws that have universal applicability and some that are applicable in specific situations. In this book and other books in this series, we will study both types of laws of physics and how to use them.

Required Mathematics. Laws of physics are usually written down in mathematical language. This allows one to further investigate and deduce their implications more fully. Consequently,to appreciate and understand physics, a student must have a solid training in mathematics. For our purposes, you must know algebra, plane geometry, elementary functions, and trigonometry. Some familiarity with Calculus will go a long way.

Emperical Science. Laws of physics are not necessarily infallible. They are always tested against reproducible experiments or observations. This makes physics an empirical science, although physicists do spend much time developing models and theories. In physics, experiments and theories complement one another, and together, they are very powerful for unlocking mysteries of nature.

Theories to Laws. Theories in physics range from the empirical to the abstract. Often a theory is simply a model or a mental image that helps grasp the experimental observations better. Theories may also suggest new experiments to render the physical situation clearer. Physicists also explore theories that seek to unearth the abstract principles that can explain a number of phenomena. Although the words - theory and model - are often used interchangeably, theories are usually understood to mean more general ideas while models usually refer to a particular phenomenon.

When many predictions of a general theory have been tested and found to be correct, the theory gains the status of a law of physics. There is a self-propelled process in the testing process. The testing of predictions of laws of physics is usually limited by development in technology, which itself is guided by a progress in physics, and/or the human ingenuity. With increased precision, or an access to some previously inaccessible physical conditions, or some hitherto unimagined experiment, the old accepted laws are often tested in new ways.

Sometimes, new tests show flaws in the accepted laws. Since many such exciting discoveries have been made in the past, physicists keep an open mind about their subject and treat the presently accepted laws as tentative. If a law is inconsistent with reliable observations, then either the law is modified or a new theory is invented to replace the old one. In this sense, physics is quite dynamic, changing continuously as our understanding of the world improves. Whether this process of correcting and replacing the old laws with new ones will ever end up with the eventual discovery of “the final laws” is unclear at this time since we do not know if such immutable final laws even exist.