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Indexed by:期刊论文

Date of Publication:2009-04-01

Journal:CHINESE PHYSICS B

Included Journals:SCIE、EI、ISTIC、Scopus

Volume:18

Issue:4

Page Number:1711-1720

ISSN No.:1674-1056

Key Words:bounce cosmology; deceleration parameter; equation of state (EOS); dark energy (DE)

Abstract:In the framework of a five-dimensional (5D) bounce cosmological model, a useful function f(z) is obtained by giving a concrete expression of deceleration parameter q(z) = q(1) + q(2)/1+ln(1+z). Then using the obtained Hubble parameter H(z) according to the function f(z), we constrain the accelerating universe from recent cosmic observations: the 192 ESSENCE SNe Ia and the 9 observational H(z) data. The best fitting values of transition redshift z(T) and current deceleration parameter q(0) are given as z(T) = 0.65(-0.12)(+0.25) and q(0) = -0.76(-0.15)(+0.15)(1 sigma). Furthermore, in the 5D bounce model it can be seen that the evolution of equation of state (EOS) for dark energy w(de) can cross over -1 at about z = 0.23 and the current value w(0de) = -1.15 < -1. On the other hand, by giving a concrete expression of model-independent EOS of dark energy w(de), in the 5D bounce model we obtain the best fitting values z(T) = 0.66(-0.08)(+0.11) and q(0) = -0.69(-0.10)(+0.10)(1 sigma) from the recently observed data: the 192 ESSENCE SNe Ia, the observational H(z) data, the 3-year Wilkinson Microwave Anisotropy Probe (WMAP), the Sloan Digital Sky Survey (SDSS) baryon acoustic peak and the x-ray gas mass fraction in clusters.