Philosophers began speculating about matter more than 2,000 years ago, but it was not until the early 1800s that John Dalton proposed the first atomic theory based on experimental evidence. Since then, scientists have made amazing strides in uncovering the mysteries of these tiny particles. Further research has revealed that the atom is not the smallest particle, but is, in fact, made up of smaller "building blocks," leading to the development of particle physics. In Atomic Structure, explore the history of atomic research, the discovery of subatomic and subatomic particles, and the ways scientists hope their work will lead them to a deeper understanding of the Big Bang.