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تسجيل مستخدم جديدIs PLANCK consistent with primordial deuterium measurements ?
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The recent measurements of the Cosmic Microwave Background Anisotropies provided by the Planck satellite experiment have significantly improved the constraints on several cosmological parameters. In this brief paper we point out a small but interesting tension present between recent values of the primordial deuterium measured from quasar absorption line systems and the same value inferred, albeit indirectly, from the Planck measurements assuming {Lambda}CDM and Big Bang Nucleosynthesis. Here we discuss this tension in detail investigating the possible new physics that could be responsible for the tension. We found that, among 8 extra parameters, only an anomalous lensing component and a closed universe could change the Planck constraint towards a better consistency with direct deuterium measurements.
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