BBN and the Primordial Abundances
نویسنده
چکیده
The relic abundances of the light elements synthesized during the first few minutes of the evolution of the Universe provide unique probes of cosmology and the building blocks for stellar and galactic chemical evolution, while also enabling constraints on the baryon (nucleon) density and on models of particle physics beyond the standard model. Recent WMAP analyses of the CBR temperature fluctuation spectrum, combined with other, relevant, observational data, has yielded very tight constraints on the baryon density, permitting a detailed, quantitative confrontation of the predictions of Big Bang Nucleosynthesis with the post-BBN abundances inferred from observational data. The current status of this comparison is presented, with an emphasis on the challenges to astronomy, astrophysics, particle physics, and cosmology
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The status of big bang nucleosynthesis (BBN) as a cornerstone of the hot big bang cosmology rests on the agreement between the theoretical predictions and the primordial abundances (as inferred from observational data) of the light elements deuterium (D), helium-3 (He), helium-4 (He), and lithium-7 (Li). The strength of BBN is that it is a testable theory: from its beginings in the late 1940’s,...
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