Question 1

In pair production,the heaviest particles are formed in reactions that have the highest temperatures.

Accepted Answer

A) True 
 B)False  True

Question 2

The ________ background radiation in fact far exceeds all the energy radiated by all the stars and galaxies that formed since then.

Accepted Answer

microwave

Question 3

Describe what occurred during the period of decoupling.

Accepted Answer

During decoupling,about 400,000 years after the Big Bang,the temperature was finally low enough (about 3,000 K)for neutral atoms to form.Before then,the universe was largely opaque to radiation since photons regularly scattered off of free electrons.When atoms formed,only photons of specific wavelengths would interact with matter,making the universe transparent to the cosmic background radiation.

Question 4

The nuclear epoch occurred during the formation of:

Accepted Answer

A)   only protons and neutrons.
B)   dark energy.
C)   deuterium and helium.
D)   all elements up to iron.
E)   all known elements.

Question 5

Which of these seems the best present answer to the horizon and flatness problems?

Accepted Answer

A)   The superforce rules creation.
B)   Dark Energy speeds the universe on out to infinity.
C)   symmetry in creation of particles and antiparticles
D)   the inflationary epoch
E)   the GUT theory

Question 6

Which of these did NOT occur at decoupling?

Accepted Answer

A)   The cosmic microwave radiation was released from matter.
B)   Neutral atoms were formed.
C)   Matter dominated radiation.
D)   Electrons began to orbit protons.
E)   The universe became transparent.

Question 7

Decoupling refers to interactions between matter and antimatter at the end of the Radiation Era.

Accepted Answer

A) True 
 B)False

Question 8

The protons,neutrons,and electrons of our atoms were made in the quark epoch.

Accepted Answer

A) True 
 B)False

Question 9

Before the decoupling,

Accepted Answer

A)   the Universe was transparent to radiation.
B)   the Universe was opaque to radiation.
C)   protons and electrons combined to form atoms.
D)   there was more helium than hydrogen.
E)   deuterium produced electrons and positrons.

Question 10

Deuterium and helium could be made only during the nuclear epoch.

Accepted Answer

A) True 
 B)False

Question 11

During the Planck Epoch,all forces were ________,and the universe was considered as a singularity.

Accepted Answer

The answer of During the Planck Epoch,all forces were ________,and...

Question 12

What key event took place during the atomic epoch?

Accepted Answer

A)   The universe expanded and cooled enough to allow the first particles to appear.
B)   The universe expanded and cooled enough for electrons to orbit protons.
C)   The neutrinos were created.
D)   Atoms in the universe collected to form stars and galaxies.
E)   The universe underwent a brief period of rapid expansion.

Question 13

Pair production is how a proton and electron are formed together from two photons,with neutrinos also given off.

Accepted Answer

A) True 
 B)False

Question 14

Cold-dark-matter models predict:

Accepted Answer

A)   large-scale filaments containing both normal matter and dark matter.
B)   no structure on a smaller scale than superclusters.
C)   the universe is less than 10 billion years old.
D)   dense regions of the early universe that led to galaxies formed after decoupling.
E)   that dark matter is the largest component of the universe's density.

Question 15

Which of these substances must be primordial?

Accepted Answer

A)   helium
B)   lithium
C)   deuterium
D)   beryllium
E)   tritium

Question 16

What happened in the atomic epoch? When was it?

Accepted Answer

The answer of What happened in the atomic epoch? When...

Question 17

Pair production can occur if:

Accepted Answer

A)   the energy of two photons is greater than the combined mass-energy of a particle-anti-particle pair.
B)   only virtual particles are produced.
C)   photons are at the event horizon of a black hole.
D)   one particle is struck by a sufficiently high energy photon that a pair of electrons is formed.
E)   the particle and antiparticle have opposite spins.

Question 18

The critical temperature for nucleosynthesis to begin was the:

Accepted Answer

A)   triple alpha reaction at 100 million K.
B)   deuterium bottleneck at about 900 million K.
C)   proton-proton cycle at 10 million K.
D)   iron production at 10 billion K.
E)   formation of lithium at 50 million K.

Question 19

Sound waves in the early universe are more technically known as ________.

Accepted Answer

The answer of Sound waves in the early universe are...

Question 20

String theories,like GUTs,explain how gravity was combined with the other fundamental forces in the very early universe.

Accepted Answer

A) True 
 B)False

Exam 27: The Early Universe: Toward the Beginning of Time

In pair production,the heaviest particles are formed in reactions that have the highest temperatures.

The ________ background radiation in fact far exceeds all the energy radiated by all the stars and galaxies that formed since then.

Describe what occurred during the period of decoupling.

The nuclear epoch occurred during the formation of:

Which of these seems the best present answer to the horizon and flatness problems?

Which of these did NOT occur at decoupling?

Decoupling refers to interactions between matter and antimatter at the end of the Radiation Era.

The protons,neutrons,and electrons of our atoms were made in the quark epoch.

Before the decoupling,

Deuterium and helium could be made only during the nuclear epoch.

During the Planck Epoch,all forces were ________,and the universe was considered as a singularity.

What key event took place during the atomic epoch?

Pair production is how a proton and electron are formed together from two photons,with neutrinos also given off.

Cold-dark-matter models predict:

Which of these substances must be primordial?

What happened in the atomic epoch? When was it?

Pair production can occur if:

The critical temperature for nucleosynthesis to begin was the:

Sound waves in the early universe are more technically known as ________.

String theories,like GUTs,explain how gravity was combined with the other fundamental forces in the very early universe.