Ruling out a critical density baryonic universe
نویسنده
چکیده
It has been suggested by Bartlett and Hall that our universe may have the critical density in baryons by virtue of specific interactions with a ‘shadow’ world. We show that this possibility is severely constrained by primordial nucleosynthesis, stellar evolution and the thermalization of the cosmic microwave background. In particular, recent observations of small angular-scale anisotropy in the cosmic microwave background conclusively rule out all such baryon-dominated cosmologies. 98.80.Cq, 97.60.Bw,98.70.Vc,98.80.Ft Typeset using REVTEX ∗PPARC Advanced Fellow hep-ph/9705331
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