Question 1

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

Accepted Answer

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

Question 2

When new particle pairs are being created as fast as they annihilate, it is:

Accepted Answer

A) hydrostatic equilibrium. 
B) thermal equilibrium. 
C) the threshold equilibrium. 
D) the cosmological constant. 
E) the critical density. 
A) hydrostatic equilibrium. 
B) thermal equilibrium. 
C) the threshold equilibrium. 
D) the cosmological constant. 
E) the critical density.

Question 3

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. 
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 4

The scarcity of what isotope is a critical test of the density of the present cosmos?

Accepted Answer

A) carbon 14 
B) deuterium 
C) helium 3 
D) helium 4 
E) lithium 5 
A) carbon 14 
B) deuterium 
C) helium 3 
D) helium 4 
E) lithium 5

Question 5

The Big Bang formed:

Accepted Answer

A) only hydrogen. 
B) only helium. 
C) hydrogen and helium, but nothing else. 
D) all elements up to iron. 
E) all elements found in nature now. 
A) only hydrogen. 
B) only helium. 
C) hydrogen and helium, but nothing else. 
D) all elements up to iron. 
E) all elements found in nature now.

Question 6

Describe qualitatively how the formation of deuterium and its current abundance is related tothe critical density of the universe.

Accepted Answer

Since stars tend to destroy deuterium, i

Question 7

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. 
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 8

What happened in the atomic epoch? When was it?

Accepted Answer

Neutral atoms of hydrogen and

Question 9

The one theory of the early universe before the Recombination Epoch and after the PlanckEpoch that was developed to resolve a conflict between observation and theory is:

Accepted Answer

A) the Grand Unified Theory. 
B) the theory of inflation. 
C) the theory of nucleosynthesis. 
D) the theory of recombination. 
E) the quantum quark theory. 
A) the Grand Unified Theory. 
B) the theory of inflation. 
C) the theory of nucleosynthesis. 
D) the theory of recombination. 
E) the quantum quark theory.

Question 10

Scientists are able to use the theories of physics to describe the conditions of the universeback to:

Accepted Answer

A) the moment of the Big Bang. 
B) the end of the Planck Epoch. 
C) the beginning of GUT. 
D) the end of the Radiation Era. 
E) the Recombination Epoch. 
A) the moment of the Big Bang. 
B) the end of the Planck Epoch. 
C) the beginning of GUT. 
D) the end of the Radiation Era. 
E) the Recombination Epoch.

Question 11

Relate the temperature of the Big Bang to pair production in the quark and lepton epochs.

Accepted Answer

The higher the temperature, the greater

Question 12

The redshift of the universe at decoupling was about:

Accepted Answer

A) Z = 1,000,000. 
B) Z = 400,000. 
C) Z = 1,100. 
D) Z = 10. 
E) Z = 4. 
A) Z = 1,000,000. 
B) Z = 400,000. 
C) Z = 1,100. 
D) Z = 10. 
E) Z = 4.

Question 13

In what sense is all observable deuterium "primordial"? Why is its abundance so important incosmology?

Accepted Answer

Deuterium is created in stellar cores no

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

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

When new particle pairs are being created as fast as they annihilate, it is:

What key event took place during the atomic epoch?

The scarcity of what isotope is a critical test of the density of the present cosmos?

The Big Bang formed:

Describe qualitatively how the formation of deuterium and its current abundance is related tothe critical density of the universe.

Which of these did NOT occur at decoupling?

What happened in the atomic epoch? When was it?

The one theory of the early universe before the Recombination Epoch and after the PlanckEpoch that was developed to resolve a conflict between observation and theory is:

Scientists are able to use the theories of physics to describe the conditions of the universeback to:

Relate the temperature of the Big Bang to pair production in the quark and lepton epochs.

The redshift of the universe at decoupling was about:

In what sense is all observable deuterium "primordial"? Why is its abundance so important incosmology?

Charting the Heavens: The Foundations of Astronomy

The Copernican Revolution: The Birth of Modern Science

Radiation: Information From the Cosmos

Spectroscopy: the Inner Workings of Atoms

Telescopes: The Tools of Astronomy

The Solar System: Comparative Planetology and Formation Models

Earth: Our Home in Space

The Moon and Mercury: Scorched and Battered Worlds

Venus: Earths Sister Planet

Mars: a Near Miss for Life

Jupiter: Giant of the Solar System

Saturn: Spectacular Rings and Mysterious Moons

Uranus and Neptune: The Outer Worlds of the Solar System

Solar System Debris: Keys to Our Origin

Exoplanets: Planetary Systems Beyond Our Own

The Sun: Our Parent Star

The Stars: Giants, Dwarfs, and the Main Sequence

The Interstellar Medium: Gas and Dust Among the Stars

Star Formation: a Traumatic Birth

Stellar Evolution: The Life and Death of a Star

Stellar Explosions: Novae, Supernovae, and the Formation of the Elements

Neutron Stars and Black Holes: Strange States of Matter

The Milky Way Galaxy: a Spiral in Space

Galaxies: Building Blocks of the Universe

Galaxies and Dark Matter: The Large-Scale Structure of the Cosmos

Cosmology: The Big Bang and the Fate of the Universe

Life in the Universe: Are We Alone

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