Use these questions to test your understanding. If you get them wrong, you will be linked back to the relevant part of the notes.
Be sure you study them thoroughly (don't just get a quick fix for your mistake) so your overall understanding is improved.
1. To a physicist studying the early Universe, unification is
a. a political movement to discredit unpopular theories
b. the concept that the fundamental forces of physics unified under extreme conditions
c. a theory combining aspects of biology and physics
d. a merger of observational and theoretical results to get a consistent picture of the early Universe
e. a process for combining different theories in a computer code
2. The period of very rapid inflation in the early Universe solves the mystery of
a. why the Universe is so uniform
b. why the Universe is expanding
c. why balloons are sometimes used to illustrate the expansion
d. why there is so much empty space
e. how the ratio of hydrogen to helium is what it is
3. Understanding how subatomic particles like quarks behave is critical to understanding
a. why the cosmic background radiation is so uniform
b. the fate of Earth in the cosmos
c. conditions in the early Universe
d. why the cosmic background is in the microwave wave spectral region
e. the structure on the cosmic background
4. The "flatness problem" refers to
a. why space-time is not curved
b. how the Universe came out just at the density that balances its gravity
c. how spiral galaxies can maintain such flat disks
d. the extreme uniformity of the cosmic background radiation
e. why we do not see peaks in mass due to matter coming from other Universes
5. You are made of
a. antimatter
b. nonbaryonic matter
c. baryonic matter
d. neutrinos
e. neutral matter
6. We know that the Universe is only about 6% protons and neutrons - baryons - because
a. if there were more, the Universe would be closed