Zooming In to Fundamental Particles

S1, E2: After touring the universe on a macro scale in the previous episode, now zoom in on the microcosmos - advancing by powers of ten into the realm of molecules, atoms, and nuclei. Learn why elementary particles are just as central to astrophysics as stars and galaxies. Then review the four fundamental forces of nature and perform a calculation that explains why atoms have to be the size they are.