Model independent analysis of dark energy: Supernova fitting result
نویسنده
چکیده
This paper uses the supernova data to explore the property of dark energy by some model independent methods. We first Taylor expand the scale factor a(t) and the luminosity distance dL to the fifth order to find out that the deceleration parameter q0 < 0. This result just invokes the Robertson-Walker metric. So the conclusion that the universe is expanding with acceleration is more general. Then we discuss several different parametrizations used in the literature. We also proposed two modified parametrizations. We find that ωDE0 is less than −1 almost at 1σ level from all the parametrizations used in this paper. We also find that the transition redshift from deceleration phase to acceleration phase is zT ∼ 0.3. PACS numbers: 98.80.-k, 98.80.Es,98.80.Cq Model independent analysis of dark energy: Supernova fitting result 2
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