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From the 1970s to the present, the accepted value of H has almost doubled, so |
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The age of the universe is half what we believed. |
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If Euclid is right, then ^o is |
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On the basis of our current best estimate of the present mass density of the universe, astronomers think that |
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the universe is infinite in extent and will expand forever. |
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The horizon problem in the standard BIG BANG model is solved by having the universe |
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inflate rapidly early in its existence. |
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Why didn't elements heavier than helium form in the first minutes of creation? |
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Homogeneity and isotropy, taken as assumptions regarding the structure and evolution of the universe, are known as: |
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the Cosmological Principle |
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the latest studies from ________ led to the discovery of "dark energy." |
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Definition
Type I supernovae at very large red shifts |
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Term
The redshift of the galaxies is correctly interpreted as |
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Definition
space itself is expanding with time, so the photons are stretched while they travel through space. |
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The satellite that found the ripples in the cosmic background that led to galaxies is |
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According to (Radiation–Matter Dominance), when the universe was 10 years old, the density of radiation was |
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Definition
much greater than that of matter |
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Term
If ^o is less than one, then |
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Definition
the universe will expand forever. |
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Term
The age of the universe is estimated to be |
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greater than the age of the Milky Way Galaxy. |
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Term
What is the meaning of a "closed" universe? |
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Definition
The universe will someday stop expanding and begin collapsing inward. |
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Term
In which of the following models will the universe stop expanding? |
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Term
The concept that the direction of observation does not matter overall is |
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In the cosmological principle, we can easily test cosmic homogeneity with the red shift surveys, but isotropy cannot be so tested. |
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Term
The presently accepted value of the Hubble constant gives an age of |
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The discovery of the cosmic microwave background was important because |
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Definition
it was was experimental verification of a prediction from the BIG BANG theory. |
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Because almost all galaxies show redshifted spectra, we know that |
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Definition
the universe is expanding. |
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Term
What temperature has the BIG BANG cooled to by now? |
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Term
The darkness of the night sky in an infinite universe is addressed in |
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hydrogen & helium, but nothing else. |
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It appears that nearly 3 x’s as much dark energy exists in the universe than normal and dark matter combined. |
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Definition
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Term
The background hiss that Bell Labs detected was the best observational evidence for the BIG BANG |
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Term
Deuterium abundance suggests that normal matter makes up only 3-4% of the critical density. |
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