How did the temperature of the early universe compare to the current density of the universe?
How might the temperature and density in the early universe create different reactions than those observed in the current universe?
Describe the stellar, galactic, and atomic epochs in the Matter Era. How long did each of these epochs last and what were the major events in each stage?
What happened in the Nuclear Epoch in the Radiation Era?
Most of the Helium in the universe was formed during primordial nucleosynthesis. Why weren't heavier elements like iron formed at this time?
What is the flatness problem? What is the horizon problem?
How does the Inflation Model solve the flatness problem and the horizon problem?
What are Grand Unified Theories?
What observations can be used to test models of the Big Bang? How can measurements of Helium and Lithium abundance be used to constrain models of the big bang?