"[H]igh energy laboratories can produce particles with energies similar to those that prevailed in the [very early] Universe... allows us to model the primordial production of small nuclei from collisions starting with s and s, long before stars began to form. Because we know... what energies are required for collisions to take apart... light elements [ less than 11] into... protons and neutrons, we can identify... the time at which the Universe became cold enough that this destruction practically ceased, and... production of elements started in earnest."