Astrophysics for People in a Hurry (Astrophysics for People in a Hurry Series)

This tepid universe was no longer hot enough or dense enough to cook quarks, and so they all grabbed dance partners, creating a permanent new family of heavy particles called hadrons (from the Greek hadros, meaning “thick”). That quark-to-hadron transition soon resulted in the emergence of protons and neutrons as well as other, less familiar heavy

Astrophysicists apply the tenets and tools of general relativity and quantum mechanics to very different classes of problems.