Astronomy Ch. 17
According to the age of the standard Big Bang theory (neglecting any effects of cosmic acceleration), what is the maximum possible age of the universe if H0=50km/s/Mpc? 70km/s/Mpc? 80km/s/Mpc?
20, 14, 12 billion years
Why isn't it correct to say that the expansion of the universe involves galaxies flying outward into empty space?
Because the space isn't empty.
Explain how an accurate measure of Hubble's constant can lead to an estimate of the age of the universe.
By dividing the distance traveled by galaxies by the rate (H0), one can determine time (age)
Hubble's law implies that the universe will expand forever.
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If the universe had an edge that fact would violate the assumption of isotropy in the cosmological principle.
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Observations suggest that the density of the universe is made up of mostly dark matter.
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Why are the observations of distant supernovae so important to cosmology?
Indicate acceleration of universal expansion, possibly via dark energy/cosmological constant.
How does the cosmological redshift relate to the expansion of the universe?
It is the measure of a photon wave length changing with respect to the expansion of the universe.
The cosmic microwave background is the highly redshifted radiation of the early Big Bang.
T
The cosmological redshift is a direct is a direct measure of cosmic expansion.
T
What is the cosmological principle?
The term for the two assumptions of homogeneity and isotropy. There is no edge to the universe and there is no center.
The galactic distances used to measure the acceleration of the universe are determined by observations of
exploding white dwarfs.
The age of the universe is estimated to be
greater than the age of the Milky Way galaxy.
On the basis of our current best estimate of the present mass of the universe, astronomers think that
the universe is infinite in extent and will expand forever.
