Question 1

What are the three possible types of universe and what features distinguish them?

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Question 2

Is there enough luminous matter to stop the universe's expansion? Is there enough dark matter? What else is there?

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Question 3

How would the geometry of a Universe with Ωₒ greater than 1 differ from one with Ωₒ less than 1?

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Question 4

Is the Hubble Constant really constant?

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Question 5

Where did the Big Bang occur?

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Question 6

The ________ is the observational evidence that the whole universe was once extremely hot and dense,as called for in the Big Bang,but has now expanded and redshifted this energy to much longer wavelengths.

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Question 7

When dark matter first became popular,many astronomers thought that was greater than one from the extra gravity,favoring what type of Universe?

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Question 8

How is the geometrical structure of the universe today related to the presence of matter in the universe? How is this related to the future history of the universe?

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Question 9

Galaxies in all directions are observed to be streaming away from us as if we were in the center of the universe.Contrast this impression with the Cosmological Principle and explain why a simple-minded interpretation of the Hubble expansion is incorrect.

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Question 10

Is the cosmological redshift really a velocity of a given galaxy?

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Question 11

When dark energy is thrown into the mix,present observational data seem to indicate that the universe will ________.

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Question 12

Does the universe have an edge or a center?

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Question 13

At present the universe is expanding,but we are not certain if this expansion will continue forever,come to a stop,or if the universe will ultimately collapse back into itself.What observational tests are possible to test among these three possibilities?

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Question 14

A decade ago,many astrophysicists thought that the oldest globular clusters were 14-16 billion years old.Why did this create problems,and how did new Hubble and Hipparcos data resolve them?

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Question 15

What is the study of cosmology?

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Question 16

How does dark energy affect the expansion of the Universe?

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Question 17

Einstein's ________ is a candidate for the dark energy that would be a repulsive force that may exist throughout space,and accelerate the expansion of the universe.

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Question 18

Contrast dark matter and dark energy with respect to their roles in the future of the universe.

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Question 19

Why can one not use quasars to check the Hubble relation relating distances of objects to their velocity of recession?

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Question 20

State the cosmological principle.

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Quiz 26: Cosmology: The Big Bang and the Fate of the Universe