Big-bang nucleosynthesis and the baryon density of the universe
- Univ. of Chicago, IL (United States)
For almost 30 years, the predictions of big-bang nucleosynthesis have been used to test the big-bang model to within a fraction of a second of the bang. The agreement between the predicted and observed abundances of deuterium, helium-3, helium-4, and lithium-7 confirms the standard cosmology model and allows accurate determination of the baryon density, between 1.7 x 10{sup {minus}31} and 4.1 x 10{sup {minus}31} grams per cubic centimeter (corresponding to about 1 to 15 percent of the critical density). This measurement of the density of ordinary matter is pivotal to the establishment of two dark-matter problems: (i) most of the baryons are dark, and (ii) if the total mass density is greater than about 15 percent of the critical density, as many determinations indicate, the bulk of the dark matter must be {open_quotes}non-baryonic,{close_quotes} composed of elementary particles left from the earliest moments. 60 refs., 6 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 70329
- Journal Information:
- Science, Journal Name: Science Journal Issue: 5195 Vol. 267; ISSN SCIEAS; ISSN 0036-8075
- Country of Publication:
- United States
- Language:
- English
Similar Records
Big Bang nucleosynthesis and the quark-hadron transition
Big bang nucleosynthesis and the quark-hadron transition