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the latest studies from _____ led to the dyscovery of dark energy |
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type I supernovae at very large red shifts |
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what temperature has the big bang cooled to by what now |
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the expansion rate of the universe is |
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the concept that on the grandest of scales the universe is similar in appearance everywhere is |
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the presently accepted value of the Hubble constant gives an age of |
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with a hubble constant of 70KM/sec/mpc the critical density would be |
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if OMEGA o is less than one |
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the universe will expand forever |
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the concept that the direction of obervation does not matter overall is |
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most of the deuterium formed right after the big bang |
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quickly burned into helium nuclei |
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the darkness of the night sky in an infinite universe is addressed in |
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how does the energy of the cosmic microwave background compare to the energy radiated by all stars and galaxies that ever existed |
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about ten times more from the big bang than from stars and galaxies |
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the tiny ripples in the background radiation COBE found are due to |
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a gravitational redshift caused by growing dark clumps |
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hydrogen and helium but very little else |
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the redshift of the galaxies is correctly interpreted as |
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space itself i expanding with time, so the photons are stretched while they travel through space |
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homogeneity and isotropy taken as aasumptions regarding the structure and evolution of the universe are known as |
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the cosmological principal |
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what key event happened during the decoupling epoch |
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expansion cooled the universe enough that protons could capture electrons in orbit |
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because almost all galaxies show redshifted spectra, we know that |
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the universe is expanding |
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what is the meaning of a closed universe |
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the universe will someday stop expanding and start to collapse |
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the best answer to both the flatness and horizon problems is |
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concerning dark energy, we predict |
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its density remains constant over time, so it is not important in the early universe |
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in the critical density universe now proposed, of the ratio of dark energy to matter i about |
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the universe was opaque to radiation |
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