Term
| What do astronomers mean by the large-scale structure of the universe? |
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Definition
| The overall arrangement of galaxies, clusters of galaxies, and superclusters in the universe. |
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Term
| When we say that the electroweak and strong forces "freeze out" at 10-35 second after the Big Bang, we mean that |
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Definition
| prior to this time the electroweak and strong forces maintained a single identity, but they possessed separate identities following this time. |
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Term
| Which of the following statements about rich clusters of galaxies (those with thousands of galaxies) is not true? |
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Definition
| Galaxies in the central regions are predominantly spirals, while elliptical galaxies roam the outskirts. |
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Term
| According to the Big Bang theory, how many forces -- and which ones --- operated in the universe during the GUT era? |
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Definition
| 2: gravity and a single force that later became the strong, weak, and electromagnetic forces. |
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Term
| Spiral galaxy rotation curves are generally fairly flat out to large distances. Suppose that spiral galaxies did NOT contain dark matter. How would their rotation curves be different? |
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Definition
| C. The orbital speeds would fall off sharply with increasing distance from the galactic center. |
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Term
| ____________describes the notion that if the universe were infinite, unchanging, and everywhere the same, then the entire night sky would be as bright as the sun. |
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Definition
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Term
| When light is collected from a region of a galaxy where the stars have different orbital speeds, the spectral lines in that spectrum will be |
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Definition
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Term
| The distribution of the dark matter in a spiral galaxy is approximately _____________times the size of the galaxy halo. |
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Definition
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Term
| The _____________ of the universe determines whether the universe will expand forever. |
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Definition
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Term
| The forces that operated in the universe during the GUT era were _______________ and ________________. |
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Definition
| gravity|GUT force, gravity|GUT force |
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