- They undergo an enormous Universe-wide phase transformation where all of the quarks and gluons in the Universe become confined together inside mesons such as the pi meson and baryons such as the proton and neutron.
- In particular, we know that the number of baryons (protons and neutrons) exceeds the number of anti-baryons.
- They're usually found in twos (as particles called mesons) and threes (as particles called baryons, such as protons and neutrons).
- The strong force is mediated by the gluon (which comes in eight flavors), which binds quarks together to form baryons and mesons and protons and neutrons together to form nuclei.
- The proton and the neutron are baryons; the electron, the muon, and the neutrino are leptons; whilst the pions are mesons.