What is Physics?

Physics is the search for the fundamental laws that describe how everything in the universe works. (A law is said to be fundamental if it cannot be explained in terms of anything more basic.) Physicists have divided the subject into branches. Some of the branches (areas of study) of Physics are: Mechanics, Thermodynamics, Waves, Acoustics, Electricity, Magnetism, Electromagnetism, Electric Circuits, Electronics, Electromagnetic Waves, Light and Optics, Atomic Physics, Nuclear Physics, Elementary Particle Physics, Relativity, Quantum Mechanics, Statistical Mechanics, Solid State Physics, Condensed Matter Physics, to name a few.

Since Physics tries to explain how everything in the universe works, Physics is the foundation upon which all other sciences are built. As such, Physics is the basis for Astronomy, Biology, Chemistry, Geology, Meteorology, Oceanography, etc. Physics is also the foundation for Engineering. Engineers take the fundamental laws of Physics, and use them to make useful devises and structures. Where does new technology come from? New technology comes from new discoveries in Physics. Engineers and inventors take these new discoveries, and make new applications. Some of the discoveries of Physics that have lead to new technologies include the transistor, the laser, x-rays, nuclear magnetic resonance, and radioactivity, to name just a few. The transistor has revolutionized the electronic industry, giving us cell phones, pagers, hand held calculators, and computers. Even the World Wide Web was developed by physicists. For a very interesting article on how these have affected society, read Contributions of Physics to The Information Age by Ian P. Bindloss from UCLA. Nuclear Magnetic Resonance has lead to Magnetic Resonance Imaging (MRI). MRI gives none invasive means to explore inside soft living tissue, practically eliminating the need for exploratory surgery. The same is true of x-rays for solid tissue, like bone. The use of radioactivity has provided a way to kill cancer cells, in order to prolong life.

What can you do with physics?

When asked this question, I usually turn it around and ask "What can't you do with physics?" Physics is involved in every area of science and technology. A degree in physics will allow you to explore a great variety of careers. Physicists work for automobile companies, aerospace companies, electronics and computer companies, communication companies, NASA, and even hospitals. If you are interested in science or technology, physics will provide you with deep understanding and technical versatility.

Consider the comments from John Sunderland, Technical Operations Director and Medical Physicist, Biomedical Research Foundation of Northwest Louisiana:

"...In the year 2000 I work at a medical isotope facility. In school I 'learned physics.' Nobody said why I needed to know physics, or if they did, I did not hear them. Today I 'live physics.' I must know physics to help save lives...
"X-rays, CT scan, and Magnetic Resonance Imaging techniques give anatomical images, such as broken bones or the presence of tumors. Positron Emission Tomography (PET) gives biochemical images, where you can see whether an organ is working as it's supposed to.
"PET uses radioactive fluorine-18, which has a half-life of 18 minutes, in cancer detection. The fluorine is bonded, for instance, to a glucose molecule, where it can enter the metabolic processes. "The fluorine-18 beta decays, emitting a positron. That positron annihilates with an electron, to produce two 5-keV gamma rays. An array of 12,000 scintillator detectors detect the two gamma rays in coincidence. From these measurements one reconstructs the sites of glucose metabolism...
"...In my work on PET imaging, I have used virtually everything I ever learned in physics, from crystallography to the photoelectric and Compton effects; from particle trajectories to imaging..."
The Physics Department Reveille, Summer 2001

Careers in Physics

Study the career wheel below to see other career opportunities that are open to you with a physics degree.

Career Wheel courtesy of the American Institute of Physics

All portions of these materials are copyright 2007 Armstrong Atlantic State University and AASU Physics.