Pick any 3 topics and explain in your own words , max 100 words each topic.
Describe how we estimate the age of the universe.
Explain how changes in the rate of expansion over time affect estimates of the age of the universe.
Describe the evidence that dark energy exists and that the rate of expansion is currently accelerating.
Describe some independent evidence for the age of the universe that is consistent with the age estimate based on the rate of expansion.
Explain how the rate of expansion of the universe affects its evolution.
Describe four possibilities for the evolution of the universe.
Explain what is expanding when we say that the universe is expanding.
Define critical density and the evidence that matter alone in the universe is much smaller than the critical density.
Describe what the observations say about the likely long-term future of the universe.
Describe what the universe was like during the first few minutes after it began to expand.
Explain how the first new elements were formed during the first few minutes after the Big Bang.
Describe how the contents of the universe change as the temperature of the universe decreases.
Explain why we can observe the afterglow of the hot, early universe.
Discuss the properties of this afterglow as we see it today, including its average temperature and the size of its temperature fluctuations.
Describe open, flat, and curved universes and explain which type of universe is supported by observations.
Summarize our current knowledge of the basic properties of the universe including its age and contents.
Specify what fraction of the density of the universe is contributed by stars and galaxies and how much ordinary matter (such as hydrogen, helium, and other elements we are familiar with here on Earth) makes up the overall density.
Describe how ideas about the contents of the universe have changed over the last 50 years.
Explain why it is so difficult to determine what dark matter really is.
Explain why dark matter helped galaxies form quickly in the early universe.
Summarize the evolution of the universe from the time the CMB was emitted to the present day.
Describe two important properties of the universe that the simple Big Bang model cannot explain.
Explain why these two characteristics of the universe can be accounted for if there was a period of rapid expansion (inflation) of the universe just after the Big Bang.
Name the four forces that control all physical processes in the universe.
Name some properties of the universe that, if different, would have precluded the development of humans.