ar X iv : a st ro - p h / 03 02 25 9 v 1 1 3 Fe b 20 03 Chemical Composition of the Early Universe
نویسنده
چکیده
A prediction of standard inflationary cosmology is that the elemental composition of the medium out of which the earliest stars and galaxies condensed consisted primarily of hydrogen and helium He with small admixtures of deuterium, lithium Li, and He. The most red-shifted quasars, galaxies, and Ly-α absorbers currently observed, however, all exhibit at least some admixture of heavier elements, as do the most ancient stars in the Galaxy. Here we examine ways in which the abundance of these same elements, if present before the epoch of population III formation, might be observationally established or ruled out. Subject headings: Cosmology: Early Universe, Observations, Theory ; Galaxies: Quasars: Absorption Lines
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