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Solving the discrepancy among the light elements abundances and WMAP

Kazuhide Ichikawa·Masahiro Kawasaki·Fuminobu Takahashi
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Abstract

Within the standard big bang nucleosynthesis (BBN) and cosmic microwave background (CMB) framework, the baryon density measured by the Wilkinson Microwave Anisotropy Probe (WMAP) or the primordial D abundance is much higher than the one measured by the $^4$He or $^7$Li abundances. To solve the discrepancy, we propose a scenario in which additional baryons appear after BBN. We show that simply adding the baryons can not be a solution but the existence of a large lepton asymmetry before BBN makes the scenario successful. These extra baryons and leptons, in addition to the initial baryons which exist before the BBN, can be all produced from $Q$-balls.

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Kazuhide Ichikawa, Masahiro Kawasaki, Fuminobu Takahashi. 2004-06-09. Solving the discrepancy among the light elements abundances and WMAP. https://doi.org/10.1016/j.physletb.2004.07.011

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