1) In quantum physics, Heisenberg's uncertainty principle says that matter and antimatter can appear spontaneously in empty space and annihilate 2) At the beginning, all the energy in the universe was in the form of neutrinos 3) By t = 1 sec, the U contained about 25 % He nuclei and the rest H nuclei 4) By t = 15 min, the Universe had cooled enough that nucleosynthesis ended 5) Our U contains mass because for every 109 + 1 matter particles there were 109 antimatter particles 6) It will never be possible to measure all properties of a particle with perfect accuracy even if our technology increases. Explain. 7) Production of particle-antiparticle pairs ended because gamma ray energy increased as the U expanded. Explain. 8) In a top-down scenario with Cold Dark Matter, large structure like galaxy clusters form first. Explain.