Question 1

How much of the total mass of the universe is made up of hot dark matter?

Accepted Answer

A)  5 percent 
B)  25 percent 
C)  45 percent 
D)  90 percent

Question 2

Structure formation in our universe

Accepted Answer

A)  proceeds from the top down. 
B)  proceeds from the bottom and moves up. 
C)  begins on all spatial scales at the same time. 
D)  begins after clusters form.

Question 3

Our current ideas on galaxy formation suggest that the visible parts of galaxies

Accepted Answer

A)  form first and are incorporated into dark matter halos later. 
B)  form only in the densest parts of dark matter halos. 
C)  can tell you the total size of the dark matter halo. 
D)  can tell you everything about the formation history of that galaxy.

Question 4

Which is NOT an ingredient needed to build a cosmological simulation of large-scale structure formation?

Accepted Answer

A)  The spectrum of density fluctuations that quantum mechanics imprints on the early universe 
B)  The density of dark matter and luminous matter in the universe 
C)  The grand unified theory 
D)  The density of dark energy in the universe

Question 5

Even at its earliest moments,the universe had about as much structure in it as it has at the current time.

Accepted Answer

A) True 
 B)False

Question 6

We expect the kinds of galaxies that we see at a redshift of 4 (that is,when the universe was much younger)to be

Accepted Answer

A)  much like what we see today. 
B)  smaller and much more irregular looking than today. 
C)  smaller versions of what we see today. 
D)  far more numerous but with fewer spiral galaxies.

Question 7

What process is most responsible for shaping the large-scale structure of the universe?

Accepted Answer

A)  Supernovae from the first generation of stars 
B)  Gravity 
C)  Matter/antimatter annihilation 
D)  Magnetic fields

Question 8

Current numerical models suggest that most of the universe is composed of hot dark matter.

Accepted Answer

A) True 
 B)False

Question 9

Explain why there could be an infinite number of multiverses inside our own universe.Are they likely to be similar or different than our own universe?

Accepted Answer

The answer of Explain why there could be an infinite...

Question 10

Describe the large-scale structure of the universe.

Accepted Answer

The answer of Describe the large-scale structure of the universe....

Question 11

The Local Group is a part of the Virgo Supercluster.

Accepted Answer

A) True 
 B)False

Question 12

In a massive cluster of galaxies,the most common type of galaxy is

Accepted Answer

A)  a spiral. 
B)  a giant elliptical. 
C)  an elliptical. 
D)  an irregular.

Question 13

Which component makes up the largest amount of mass in a typical large cluster of galaxies?

Accepted Answer

A)  Supermassive black holes 
B)  Stars 
C)  Cold gas 
D)  Hot gas

Question 14

The most common type of galaxy found in a galaxy cluster is a

Accepted Answer

A)  spiral. 
B)  giant elliptical. 
C)  giant irregular. 
D)  dwarf.

Question 15

What is the fundamental difference between the two basic types of dark matter? List an example of each type.

Accepted Answer

The answer of What is the fundamental difference between the...

Question 16

What do astronomers believe will be the final state of our universe?

Accepted Answer

A)  A "Big Crunch" in which everything collapses back in on itself 
B)  An ever-expanding universe filled with nothing but hydrogen and helium gas 
C)  A universe that stops expanding and is filled with nothing but white dwarfs,neutron stars,and black holes 
D)  An ever-expanding universe filled with photons and elementary particles

Question 17

As structure formed in the universe,galaxy-sized objects formed before cluster-sized objects.

Accepted Answer

A) True 
 B)False

Question 18

In the early universe,why were inhomogeneities in the distribution of normal matter much smaller than the inhomogeneities in the dark matter?

Accepted Answer

A)  Radiation pressure affected normal matter but not dark matter. 
B)  Magnetic fields smoothed the distribution of charged particles in the normal matter but not in dark matter. 
C)  Dark matter particles were more massive and cooled off before normal matter,thus dark matter fluctuations had a longer time over which to grow. 
D)  Dark matter was ten times more massive than normal matter.

Question 19

Which of the following CANNOT be dark matter?

Accepted Answer

A)  Axions 
B)  Positrons 
C)  Photinos 
D)  Neutrinos

Question 20

Structure formation in the universe proceeds hierarchically,meaning that

Accepted Answer

A)  large objects collapse then fragment to form smaller objects. 
B)  large objects form at the same times as smaller objects. 
C)  small objects collapse then merge to form larger objects. 
D)  only small objects form and are stable over time.

Exam 22: The Origin of Structure

How much of the total mass of the universe is made up of hot dark matter?

Structure formation in our universe

Our current ideas on galaxy formation suggest that the visible parts of galaxies

Which is NOT an ingredient needed to build a cosmological simulation of large-scale structure formation?

Even at its earliest moments,the universe had about as much structure in it as it has at the current time.

We expect the kinds of galaxies that we see at a redshift of 4 (that is,when the universe was much younger) to be

What process is most responsible for shaping the large-scale structure of the universe?

Current numerical models suggest that most of the universe is composed of hot dark matter.

Explain why there could be an infinite number of multiverses inside our own universe.Are they likely to be similar or different than our own universe?

Describe the large-scale structure of the universe.

The Local Group is a part of the Virgo Supercluster.

In a massive cluster of galaxies,the most common type of galaxy is

Which component makes up the largest amount of mass in a typical large cluster of galaxies?

The most common type of galaxy found in a galaxy cluster is a

What is the fundamental difference between the two basic types of dark matter? List an example of each type.

What do astronomers believe will be the final state of our universe?

As structure formed in the universe,galaxy-sized objects formed before cluster-sized objects.

In the early universe,why were inhomogeneities in the distribution of normal matter much smaller than the inhomogeneities in the dark matter?

Which of the following CANNOT be dark matter?

Structure formation in the universe proceeds hierarchically,meaning that