Nucleosynthesis is the process of creating new atomic nuclei from pre-existing nucleons (protons and neutrons). It is thought that the primordial nucleons themselves were formed from the quark-gluon plasma from the Big Bang as it cooled below two trillion degrees. A few minutes afterward, starting with only protons and neutrons, nuclei up to lithium and beryllium (both with mass number 7) were formed, but only in relatively small amounts. Then the fusion process essentially shut down due to dro… (More on Nucleosynthesis)