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发帖数: 402 | 1 Exploding the Big Bang
David Pratt
If light from stars or galaxies is passed through a prism or grating, a
spectrum is obtained, consisting of a series of lines and bands. These
spectra can be used to identify the atomic elements present in the objects
concerned, as each element has a distinct spectral "signature." But if we
compare the spectral lines of distant galaxies with those produced by the
same elements on earth, we find that in every case the lines are displaced
towards longer (redd |
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