64 citations · 202 across the 12 of their papers we have counts for
6 papers · 1 filter
Fluctuation of the Hubble parameter
Xi-Bin Li, Hao-Feng Qin, Zhi-Song Zhang +1
We study the Hubble parameter in perturbed Friedmann universe and obtain an expression of the perturbed Hubble parameter . We derive the Hubble parameter po…
An improved method to test the Distance--Duality relation
Xi Yang, Hao-Ran Yu, Zhi-Song Zhang +1
Many researchers have performed cosmological-model-independent tests for the distance duality (DD) relation. Theoretical work has been conducted based on the results of these tests…
Reconstruction and constraining of the jerk parameter from OHD and SNe Ia observations
Zhong-Xu Zhai, Ming-Jian Zhang, Zhi-Song Zhang +2
Compared with the plentiful researches of the Hubble parameter and deceleration factor, the third time derivative of the scale factor in the FRW cosmology, namely, the jerk…
Cosmological constraints on holographic dark energy models under the energy conditions
Ming-Jian Zhang, Cong Ma, Zhi-Song Zhang +2
We study the holographic and agegraphic dark energy models without interaction using the latest observational Hubble parameter data (OHD), the Union2.1 compilation of type Ia super…
Testing the Copernican Principle with Hubble Parameter
Zhi-Song Zhang, Tong-Jie Zhang, Hao Wang +1
Using the longitudinal expression of Hubble expansion rate for the general Lemaître-Tolman-Bondi (LTB) metric as a function of cosmic time, we examine the scale on which the Copern…
Estimations of the cosmological parameters from the observational variation of the fine structure constant
Zhong-Xu Zhai, Xian-Ming Liu, Zhi-Song Zhang +1
We present the constraints on the Quintessence scalar field model from the observational data of the variation of the fine structure constant obtained from Keck and VLT telescopes.…