Question 1

Which of the following is not consistent with observations of the cosmic microwave background?

Accepted Answer

Observations of the cosmic microwave background suggest that the universe is roughly 13.8 billion years old, so choice D is not consistent with those observations. The other choices are consistent with observations.

Question 2

Which adjective does not necessarily describe a known feature of the early universe? (Be sure to consider the universe as a whole, not just the observable universe.)

Accepted Answer

The early universe is commonly described as dense, hot, and filled with intense radiation. However, "small" does not necessarily describe a known feature of the early universe, as the size of the universe as a whole is not well-defined or understood in the context of its early stages.

Question 3

Based on observations of the cosmic microwave background, the overall composition of the universe is ________.

Accepted Answer

The observations of the cosmic microwave background suggest that the overall composition of the universe is 4% ordinary (baryonic) matter, 23% non-ordinary (nonbaryonic) dark matter, and 73% dark energy. This is known as the Lambda-CDM model of the universe.

Question 4

The Big Bang theory seems to explain how elements were formed during the first few minutes after the Big Bang. Which hypothetical observation below (these are not real observations) would call our current theory into question?

Accepted Answer

The answer of The Big Bang theory seems to explain...

Question 5

How does the idea of inflation account for the existence of the "seeds" of density from which galaxies and other large structures formed?

Accepted Answer

Inflation theory proposes that quantum fluctuations were stretched to astronomical scales during the rapid expansion of the universe in the first moments after the Big Bang. These fluctuations provided the initial seeds of density that grew over time to form the galaxies, clusters, and superclusters we observe today.

Quiz 17: The Beginning of Time

Which of the following is not consistent with observations of the cosmic microwave background?

Which adjective does not necessarily describe a known feature of the early universe? (Be sure to consider the universe as a whole, not just the observable universe.)

Based on observations of the cosmic microwave background, the overall composition of the universe is ________.

The Big Bang theory seems to explain how elements were formed during the first few minutes after the Big Bang. Which hypothetical observation below (these are not real observations) would call our current theory into question?

How does the idea of inflation account for the existence of the "seeds" of density from which galaxies and other large structures formed?