Deck 29: The Big Bang

Question 1

When do astronomers now think that the "dark energy" began to accelerate the expansion of the universe?

A) right after the Big Bang (after the first three minutes or so)
B) a few million years after the Big Bang
C) several billion years after the Big Bang
D) about ten million years ago
E) when the city of Bayonne, New Jersey was founded

Answer 1

several billion years after the Big Bang

Question 2

Which of the following is the Earth not located in?

A) the solar system
B) the universe
C) globular cluster M-13
D) the Milky Way Galaxy
E) the Earth is located in all of the above

Answer 2

globular cluster M-13

Question 3

Factoring in everything we currently know about the history of the universe, our best estimate for the age of the universe is

A) 4.6 billion years
B) about 100 billion years
C) roughly 2 million years
D) about 13.8 billion years
E) the age of the universe is infinite; there was no beginning

Answer 3

about 13.8 billion years

Question 4

Recent observations indicate that the universe is expanding faster today than it was a few billion years ago (that, in other words, the expansion of the universe is accelerating.) What kind of observations have led astronomers to this surprising conclusion?

A) the measurements of cepheid variables in the galaxies of the Local Group
B) the measurement of galaxy distances using Type Ia supernovae
C) the discovery of large amounts of dark matter in the halo of the Milky Way
D) the measurements of the amount of deuterium in the universe
E) the fact that galaxies today are getting a lot more speeding tickets than they used to
Section 29.3: The Beginning of the Universe

Question 5

In our modern view of the expansion of the universe, we understand that it is space that is stretching; individual galaxies don't speed away from each other as if they were rockets. In that case, why do galaxies show a red-shift?

A) as galaxies age, they get redder and redder
B) as space stretches, the waves of radiation in space also stretch and their wavelength increases
C) as space stretches, the presence of dark matter slows down the light between galaxies
D) as time goes on, waves in space encounter more and more dust, and get redder
E) astronomers cannot think of any good explanation for the red-shift if it's space that expands/stretches

Question 6

Which of the following statements about the early universe (as envisioned by the standard model of cosmology) is FALSE?

A) as the universe expands, its temperature decreases
B) at the beginning, the temperature was hot enough to turn energy into matter
C) at the very beginning, the energies were so great that the universe was actually contracting for a while
D) at the beginning, the universe was not transparent to electro-magnetic radiation
E) at the very beginning, anti-matter (as well as matter) was present in significant quantities

Question 7

The first scientist to propose a specific model (the primeval atom model) for the big bang was

A) Lemaitre
B) Hubble
C) Sandage
D) Peebles
E) Nobel

Question 8

After the Big Bang, in order for the universe to become transparent to light and other electro-magnetic radiation, what had to happen?

A) stars and galaxies had to form
B) the whole universe had to be hotter than the interior of a star
C) the density of the universe had to decrease (to 1000 nuclei per cubic centimeter or less)
D) the dark energy had to dominate over regular matter and energy
E) telescopes had to be invented

Question 9

The standard bulbs (standard candles) that made it possible for astronomers to discover the acceleration in the expansion of the universe were

A) globular clusters
B) Cepheid variable stars
C) the brightest irregular galaxy in a rich cluster
D) Type Ia supernovae
E) the size of a galaxy dark matter halo

Question 10

The reciprocal of the Hubble constant (1/H) is a rough measure of the:

A) the period of a typical Cepheid variable
B) the distance to the last galaxies that formed
C) the age of the universe
D) the luminosity of a type I supernova explosion
E) the cost of building a telescope in space

Question 11

Which of the following did NOT happen during the first few minutes after the Big Bang?

A) temperatures throughout the universe were hotter than the cores of stars are today
B) two or three of the simplest elements fused together
C) energy was converted to matter
D) some very massive early stars formed
E) matter and antimatter collided and turned into energy

Question 12

Today, we believe that only a small number of elements were actually formed during the Big Bang. Which of the following was NOT one of these:

A) hydrogen
B) carbon
C) lithium
D) helium
E) you can't fool me, all of the above were definitely formed during the big bang

Question 13

Which of the following is pretty good evidence that the universe began with a Big Bang?

A) the fact that galaxies collide
B) the fact that stars explode
C) the fact that all the galaxies are moving toward us
D) the existence of a double star system like Cygnus X-1
E) the 3-degree cosmic microwave background radiation

Question 14

Why did Einstein introduce the cosmological constant into the equations of his General Theory of Relativity when describing the universe?

A) Einstein did not realize that black holes would exist at the centers of galaxies and pull everything into them
B) Einstein's equations required the universe to expand or contract; he could not imagine or accept it doing either one, so he put a factor in to stop it from moving
C) Einstein talked to Hubble and learned about Hubble's observations of the expanding universe, which made him so uncomfortable that he decided to change his equations
D) Einstein had a hunch that the universe was accelerating (speeding up its expansion) back in 1918 and so introduced the constant into his equations to describe that
E) Einstein liked cups of tea in the afternoon, and his constant was a comment on that habit

Question 15

When we determine the age of the universe using the Hubble Time, what important simplifying assumption goes into our calculations?

A) that the expansion of the universe has been happening at the same rate - neither speeding up or slowing down
B) that all the galaxies are moving away from us at exactly the same speed, no matter how far away they are
C) that the cosmological principle doesn't hold: the universe is not isotropic and homogeneous
D) that we have accounted correctly for the effects of dark energy
E) that the universe is actually contracting instead of expanding

Question 16

Astronomers have measured that there is more helium in the universe than can be explained by the fusion in stars over the last 13 billion years. How do they think the extra helium got into the universe?

A) the extra helium was produced in the accretion disks of supermassive black holes
B) the extra helium was made during the first few minutes of the Big Bang, when the entire universe was hot enough for fusion to occur briefly
C) the extra helium was produced by the interaction of dark matter with the material at the edges of all galaxies
D) the extra helium was produced recently during Type Ia supernova explosions
E) the idea that there is extra helium has been shown to be in error; we were confused by the high red shifts of distant galaxies distorting their spectra
Section 29.4: The Cosmic Microwave Background

Question 17

At about 1 second after the beginning of the universe, one type of particle was able to start traveling freely through the universe. These particles are still with us, but they are extremely hard to detect. They are called:

A) photons
B) protons
C) electrons
D) neutrinos
E) college presidents

Question 18

Based on many surveys of the average density of matter in the universe (regular matter and dark matter), astronomers now conclude that the average density of the universe is

A) less than the critical density
B) exactly equal to the critical density
C) more than the critical density
D) essentially equal to zero
E) so great that the universe will experience a "big crunch" before the Sun becomes a red giant

Question 19

In the very distant future, given our best model of the accelerating universe, what will the universe look like?

A) all the galaxies will start showing blue-shifts
B) the universe will look pretty much the same as it does today
C) the entire universe will become one huge black hole
D) all the stars will die and the galaxies will be dark
E) galaxies will shine even more brightly than today from all the dark energy

Question 20

If we include the effects of deceleration in our calculations of the age of the universe, the age we get is:

A) greater than the Hubble time
B) less than the Hubble time
C) equal to the Hubble time
D) either greater or less depending on the amount of deceleration
E) you can't fool me; this question cannot be answered without knowing the exact value of the Hubble constant.
Section 29.2: A Model of the Universe

Question 21

Which of the following statements about dark matter is FALSE:

A) it is observed to be a major part of the Milky Way
B) it is observed to be present in other groups of galaxies
C) astronomers have a pretty good idea what the dark matter is made of
D) we can detect its gravity, even though we can't see it
E) it may make up even more of the universe that the matter we can see

Question 22

The first satellite (spacecraft with instruments) to measure and confirm the cosmic microwave background was the:

A) COBE (COsmic Background Explorer)
B) Hubble Space Telescope
C) Einstein
D) Voyager 1
E) Chandra

Question 23

The satellite that has given us the most precise measurements of the characteristics of the cosmic background radiation is:

A) Planck
B) Einstein
C) the Hubble Space Telescope
D) BeppoSAX
E) Io

Question 24

The two scientists who first discovered the cosmic microwave background radiation were:

A) Hubble and Humason
B) Einstein and Friedmann
C) Gamow and Alpher
D) Penzias and Wilson
E) Kirk and Spock

Question 25

Where in space did the expansion of the universe begin?

A) at the center of the Milky Way Galaxy; that's why all the other galaxies are moving away from us
B) near the center of the Virgo Supercluster of Galaxies
C) at a point so far away that only our largest telescopes can show us glimpses of it
D) everywhere at once
E) nowhere at all; new observations show that the universe is not expanding after all

Question 26

According to the models of the universe we discussed in this course, why do the galaxies move apart (why do we have Hubble's law)?

A) gravity is a repulsive force, once you get outside the Milky Way Galaxy
B) each galaxy has net charge on it, and they repel by the laws of electricity
C) supernova explosions happen more frequently on one side of each galaxy, giving the entire galaxy a push that moves it away from its neighbors
D) as a result of the Big Bang, space itself is stretching, and this stretching carries the galaxies away from each other
E) strong political and religious disagreements among the galaxies
Section 29.5: What is the Universe Really Made of?

Question 27

Scientists looking at an overview of physics today understand that there are four forces that govern all action in the universe. These four forces are the strong nuclear force, the weak nuclear force, electro-magnetism and

A) gravity
B) dark matter
C) fusion
D) inflation
E) the force that Luke learned to use in Star Wars

Question 28

One of the things that our current "standard model" of the Big Bang Theory doesn't explain is

A) why the universe is expanding
B) why there is a cosmic microwave background filling all of space
C) why the temperature of the cosmic microwave background is so uniform throughout all of space
D) why there is more helium in the universe than stars could have produced in 13.8 billion years
E) why the galaxies show a red shift

Question 29

In describing the universe using his equations of general relativity, Einstein assumed that it was isotropic (the same in all directions.) What recent observations have confirmed that the universe is isotropic on the large scale?

A) the discovery of pulsars
B) the discovery of cannibal galaxies
C) measurements of the 3-degree cosmic background radiation
D) measurements of neutrinos from Supernova 1987A
E) the discovery that there is really nothing very good on TV, no matter which way you point your dish (antenna)

Question 30

According to our modern theories, the geometry of the entire universe (all of space-time) may be curved or warped. This is a pretty bizarre notion; what other discovery in astronomy has helped us believe that space may be able to curve or warp?

A) supernova explosions and the elements they produce
B) how the light output of cepheid variables changes with time
C) the existence of dwarf elliptical galaxies
D) the properties of black holes
E) the error in the shape of the mirror on the Hubble Space Telescope

Question 31

Scientists speculate that the properties (laws) of the universe must be the way they are because if they were significantly different, we would not be here to think about them. This idea is called

A) the cosmological principle
B) the Hubble law
C) the narcissus conjecture
D) the anthropic principle
E) the inflationary self-image hypothesis

Question 32

Some scientists speculate that our universe is not the only universe that exists, but the only one we can gather evidence about. This idea is called

A) the Big Bang theory
B) the cosmological principle
C) the multiverse theory
D) Hubble's Law
E) the accretion disk hypothesis

Question 33

What is the strongest known force in the universe?

A) gravity
B) the electromagnetic force
C) the weak nuclear force
D) the strong nuclear force
E) The Dallas Cowboys [put in your favorite local sports team here]

Question 34

According to the most recent data from satellites making precise measurements of the properties of the cosmic background radiation (CBR),

A) normal matter (like the atoms in our bodies) makes up 99% of the total mass-energy of the universe
B) dark matter makes up less than 5% of the total mass-energy of the universe; it's only a minor contributor to what makes up the cosmos
C) the dark energy makes up just a little less than 70% of the density of the universe, making it the most significant constituent of the mass-energy
D) normal matter, dark matter, and dark energy each contribute about 1/3 of the total density of the universe - their contributions are almost exactly equal
E) the universe is only about 6,000 years old
Section 29.6: The Inflationary Universe

Question 35

The model of the universe that involves an enormous increase of scale during a very short time in the early universe is called:

A) the flat universe model
B) the oscillating universe model
C) the primeval atom model
D) the inflationary universe model
E) the cosmic burp model

Question 36

How does a period of extremely fast inflation very early in the history of the universe explain the observation that the geometry of the universe looks flat (not curved) to us?

A) during inflation a lot of the mass drained out of the universe, leaving its gravity much weaker
B) inflation increased the size of the universe so much that the resulting universe looks flat from any point of view
C) inflation led to the production of so much dark matter that the universe got pulled into the shape of a black hole
D) inflation caused the temperature of different parts of the universe that can't see each other still be the same
E) The universe is actually highly curved and not flat
Section 29.7: The Anthropic Principle

Question 37

If you want to check on what conditions were like in the universe a few hundred thousand years after the Big Bang, what sort of instrument would it be best to use:

A) a gamma-ray or high-energy x-ray telescope in orbit
B) a tank of chlorine deep inside the Earth
C) a small refractor (which gathers visible light) on a college campus, but pointed in just the right direction
D) an ultra-violet telescope in orbit around Jupiter
E) a satellite with infrared and microwave telescopes on board

Question 38

According to our textbook, roughly what percent of the mass and energy contents of the universe is made up of dark matter plus dark energy?

A) 5 percent
B) 10 percent
C) 50 percent
D) 95 percent
E) astronomers have no way of estimating this percentage

Question 39

At first, right after the Big Bang, the universe was too hot for nuclei and electrons to combine into the kinds of neutral atoms that are familiar to us today. How soon after the beginning did it become cool enough for neutral atoms to form?

A) 10^-43 seconds
B) 3 minutes
C) a few hundred thousand years
D) a billion years
E) only last Thursday