If individuals have a greater interest in the science of non-living systems, they may want to continue their physical science studies at the graduate level. Subjects in this area include, but are not limited to, astronomy, atmospheric science and meteorology, chemistry, earth science, geochemistry, geology, metallurgy, nuclear science and physics. While each discipline has its own unique courses, students who pursue a Doctor of Philosophy in Physics may focus on topics such as applied physics and kinetics and go on to work as an astrophysicist or professor. Those who choose to study chemistry at the doctoral level learn about quantum mechanics and physical biochemistry and may work as general or forensic chemists.