Multiple Choice
Why is flatness a problem in cosmology?
A) The total amount of known matter (even if dark matter is included) is not enough to make the universe flat.
B) The universe appears to be flat to within observational error, yet the universe is expanding, and it is impossible for an expanding universe to be flat.
C) The universe appears to have a hyperbolic geometry to within observational error, yet the universe is expanding, and expanding universes have to be flat.
D) Matter is known to create bumps in the geometry of spacetime; therefore, the universe cannot be flat.
Correct Answer:

Verified
Correct Answer:
Verified
Q206: What makes gravity the main force determining
Q207: What kind of curvature (geometry of space)
Q208: If the cosmic microwave background radiation is
Q209: Approximately when did the inflationary period begin?<br>A)
Q210: What kind of curvature (geometry of space)
Q212: Suppose H<sub>0</sub> = 71 km/s/Mpc. What is
Q213: At what times during the Big Bang
Q214: What designation do astronomers give to the
Q215: The symmetry breaking that led to the
Q216: What is the cosmic microwave background radiation?<br>A)