http://arxiv.org/abs/1503.02439
Observations indicate that most universal matter are invisible and gravitational constant $G(t)$ maybe depends on the time. The theory of variation of $G$ (VG) is explored in this paper, with naturally resulting to the invisible components in universe. We utilize the observational data: lookback time data, model-independent gamma ray bursts data, growth function of matter linear perturbations, type Ia supernovae data with systematic errors, cosmic microwave background, and baryon acoustic oscillation data from the radial scale measurement and the peak-positions measurement, to restrict the unified model (UM) of dark components in VG theory. Using the best-fit values of parameters with the covariance matrix, constraints on the variation of $G$ are $(\frac{G}{G_{0}})_{z=3.5}\simeq 1.0003^{+0.0014}_{-0.0016}$ and $(\frac{\dot{G}}{G})_{today}\simeq 0.7977^{+2.3566}_{-2.3566}\times 10^{-13} yr^{-1}$ in a flat geometry, the small uncertainties around constants. Limit on equation of state of dark matter is $w_{0dm}=0.0151^{+0.0171}_{-0.0171}$ with assuming $w_{0de}=-1$ in the UM model, and dark energy is $w_{0de}=-0.9986^{+0.0011}_{-0.0011}$ with assuming $w_{0dm}=0$ at prior. Restriction on UM parameters are $B_{s}=0.7662^{+0.0127+0.0248}_{-0.0125-0.0269}$ and $\alpha=0.0204^{+0.0201+0.0425}_{-0.0217-0.0398}$ with $1\sigma$ and $2\sigma$ confidence level. For the non-flat case, at $1\sigma$ confidence level the $\Lambda$CDM ($\Omega_{k}=0$, $\beta=0$ and $\alpha=0$) is not included in VG-UM model, and larger errors are given: $\Omega_{k}=-0.0311^{+0.0259+0.0517}_{-0.0248-0.0501}$, $(\frac{G}{G_{0}})_{z=3.5}\simeq 0.9917^{+0.0104}_{-0.0131}$ and $(\frac{\dot{G}}{G})_{today}\simeq 19.3678^{+21.8262}_{-21.8262}\times 10^{-13}yr^{-1}$.
J. Lu, Y. Xu, Y. Wu, et. al.
Tue, 10 Mar 15
65/77
Comments: 14 pages,4 figures
You must be logged in to post a comment.