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arXiv · astro-ph/0504650

Constraints on the dark energy equation of state from the separation of CMB peaks and the evolution of alpha

Abstract

We introduce a simple parametrization of the dark energy equation of state, ω, which is motivated from theory and recent experimental data. The theory is related to the tracker solution to alleviate the fine tuning problem. Recent experimental data indicates that the present value of ωis close to -1. We analyze the evolution of ωfrom the separation of CMB peaks and the time variation of the fine structure constant, α. We find that -1.00 \leq ω^{(0)} \leq -0.971_{-0.027}^{+0.017} and 1.76_{-0.42}^{+0.29} \times 10^{-4} \leq (d ω/ dz)_{z=0} \leq 0.041_{-0.037}^{+0.016} at 95% confidence level (CL).

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Seokcheon Lee. 2005-04-28. Constraints on the dark energy equation of state from the separation of CMB peaks and the evolution of alpha. https://doi.org/10.1103/physrevd.71.123528

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