A Lower Bound on the Cosmic Baryon Density
نویسندگان
چکیده
منابع مشابه
A Lower Bound on the Cosmic Baryon Density
We derive lower bounds on the cosmic baryon density from the requirement that the high-redshift intergalactic medium (IGM) contain enough neutral hydrogen to produce the observed Lyα absorption in quasar spectra. The key theoretical assumption that leads to these analytic bounds is that absorbing structures are no more extended in redshift space than they are in real space. This assumption migh...
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The comparison of cosmic abundances of the light elements with the density of baryonic stars and gas in the universe today provides a critical test of big bang theory and a powerful probe of the nature of dark matter. A new technique allows determination of cosmic deuterium abundances in quasar absorption clouds at large redshift, allowing a new test of big bang homogeneity in diverse, very dis...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 1997
ISSN: 0004-637X,1538-4357
DOI: 10.1086/304893