Temporal variation of coupling constants and nucleosynthesis
نویسندگان
چکیده
منابع مشابه
Time variation of fundamental constants, primordial nucleosynthesis, and the size of extra dimensions.
In theories with extra dimensions, the dependence of fundamental constants on the volume of the compact space allows one to use primordial nucleosynthesis to probe the structure of compact dimensions during the first few minutes after the big bang. Requiring the yield of primordial He to be within acceptable limits, we find that in ten-dimensional superstring models the size of the extra dimens...
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We determine the influence of a variation of the fundamental “constants” on the predicted helium abundance in Big Bang Nucleosynthesis. The analytic estimate is performed in two parts: the first step determines the dependence of the helium abundance on the nuclear physics parameters, while the second step relates those parameters to the fundamental couplings of particle physics. This procedure ...
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ژورنال
عنوان ژورنال: Nuclear Physics A
سال: 2003
ISSN: 0375-9474
DOI: 10.1016/s0375-9474(03)00933-3