The Primordial Helium Abundance
نویسنده
چکیده
The primordial abundance of He, YP , is one of the hottest themes in present-day astronomy, mostly due to its cosmological relevance. The disagreement between different determinations has been currently reduced to the 1-2% level, but these differences are still large enough to have deep implications for Big-Bang nucleosynthesis. It is therefore crucial to estimate precisely the uncertainties involved in the measurement of YP . Here, I review the methods used in the determination of YP and the related uncertainties. I also discuss some recent results, and emphasize the assumptions underlying the differences among them.
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