ABSTRACT

One of the oldest problems in physics-and in all of science-is the question of what everything is made of. ere’s a natural curiosity about this that children express and that is seen throughout world cultures. e approach we have followed for many centuries is to try to understand matter by breaking it into smaller and smaller pieces, looking for fundamental building blocks. is search has led to our understanding of the atomic nature of matter. at is, all matter we normally see or encounter is made up of atoms, with the wide variety of matter explained by different combinations of atoms. More in-depth study of atoms has shown that they are not solid bodies, but instead are made up of a small atomic nucleus plus electrons. In the last century, research on the nucleus has led to a deeper understanding of its nature and a variety of applicationssome useful and others terrifying. In this chapter we’ll address some of the fundamental ideas about atoms and nuclei.