ar X iv : h ep - t h / 02 05 05 5 v 2 6 N ov 2 00 2 Can the clustered dark matter and the smooth dark energy arise from the same scalar field ?
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چکیده
Cosmological observations suggest the existence of two different kinds of energy densities dominating at small (< ∼ 500 Mpc) and large (> ∼ 1000 Mpc) scales. The dark matter component, which dominates at small scales, contributes Ωm ≈ 0.35 and has an equation of state p = 0, while the dark energy component, which dominates at large scales, contributes ΩV ≈ 0.65 and has an equation of state p ≃ −ρ. It is usual to postulate weakly interacting massive particles (WIMPs) for the first component and some form of scalar field or cosmological constant for the second component. We explore the possibility of a scalar field with a Lagrangian L = −V (φ) √
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تاریخ انتشار 2008