[09] Cosmology

Question 1

What is the branch of astronomy that studies the universe as a whole?

Answer 1

Cosmology

Question 2

What does cosmology study about the universe?

Answer 2

• Birth of the universe
• Growth of the universe
• Shape of the universe
• Size of the universe
• Eventual fate of the universe

Question 3

What theory explains the birth of the universe?

Answer 3

The Big Bang Theory

Question 4

What is Dark Matter?

Answer 4

An unseen substance that makes up about 27% of the universe; it influences the formation and structure of galaxies.

Question 5

What is Dark Energy?

Answer 5

A hypothetical form of energy that makes up about 68% of the universe; it is believed to be responsible for the accelerating expansion of the universe.

Question 6

What event is believed to be the “birth” of the universe in cosmology?

Answer 6

The Big Bang

Question 7

How does cosmology study the growth of the universe?

Answer 7

Through observations of galaxies, star formation, and cosmic microwave background radiation

Question 8

What is the current understanding of the shape of the universe in cosmology?

Answer 8

It is considered to be flat, based on data from the cosmic microwave background radiation

Question 9

How does cosmology estimate the size of the universe?

Answer 9

Through calculations based on Hubble’s law and observations of the cosmic microwave background

Question 10

What are some theories about the eventual fate of the universe studied in cosmology?

Answer 10

• Heat death (Universe continues expanding and cools down)
• Big Crunch (Universe collapses in on itself)
• Big Rip (Expansion of Universe accelerates until everything is torn apart)

Question 11

What is the “Heat Death” theory about the fate of the universe?

Answer 11

It’s a theory suggesting the universe will continue to expand and cool until it reaches a state of no thermodynamic free energy, meaning no new processes can occur

Question 12

What causes the “Heat Death” of the universe?

Answer 12

The unceasing expansion and the law of entropy

Question 13

What is the “Big Crunch” theory about the fate of the universe?

Answer 13

It’s a theory suggesting the expansion of the universe will eventually reverse, causing it to collapse in on itself

Question 14

What could happen after a “Big Crunch”?

Answer 14

Possibly a new “Big Bang”, creating a cyclic model of the universe

Question 15

What is the “Big Rip” theory about the fate of the universe?

Answer 15

It’s a theory suggesting the expansion of the universe could accelerate until all matter and spacetime is torn apart

Question 16

What would cause a “Big Rip”?

Answer 16

An increase in the force of dark energy over gravity causing an accelerated expansion