What is particle physics?

Particle physics is the study of the fundamental building blocks of matter, called elementary particles. Particle physicists try to find out what particles exist, what their properties are, and how they interact with each other.

The smallest and the largest scales of the universe are connected in interesting ways. The evolution of the universe, from its formation to the present day, depends on what particles are present in it and how they behave. Particle physics experiments and theories have a large impact on cosmology, the study of the universe as a whole.