Variation of the fine structure constant in QSO spectra from coherent dark matter oscillations
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چکیده
We consider the problem of the evolution of the fine structure coefficient α under the assumption that the scalar field coupling to the Maxwell term satisfies the condition mt ≫ 1 for coherent dark matter oscillations. In this case we find that the coupling scale f in the leading order coupling −(φ/4f)FμνF μν affects the cosmological evolution of α according to ln(α/α0) ∝ ξ(mPl/f)× ln(tanh(t/2τ)/ tanh(t0/2τ)). A fit to the QSO observations by Murphy et al. yields f = ξ × 2.12 −0.37 × 10 mPl. Here mPl = (8πGN ) −1/2 is the reduced Planck mass, and ξ = ̺φ/̺m parametrizes the contribution of φ to the matter density in the universe.
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تاریخ انتشار 2004