Particle Physics and Cosmology in Physics

This topic asks the smallest question and the largest one at the same time. What is matter made of, and how did it get here. The answers turn out to be connected, because the conditions in the first moments of the universe were energetic enough to produce every kind of particle, and the account of that early history is tested against the particles that exist today. Along the way physics had to give up on some comfortable ideas, since protons and neutrons are not fundamental, quarks cannot be pulled out on their own, and ordinary matter turns out to be a small minority of what the universe contains. The blocks give the four forces and how the carrier mass sets their range, the annihilation and pair production relations, the classification of particles with the conservation laws that govern them, the quark picture, and the cosmic results that follow from an expanding universe.