Lookback time as a test for f(R) gravity in the Palatini approach  

作　　者：Zhong-Xu Zhai Wen-Biao Liu 

机构地区：[1]Department of Physics, Institute of Theoretical Physics, Beijing Normal University, Beijing100875, China

出　　处：《Research in Astronomy and Astrophysics》2011年第11期1257-1265,共9页天文和天体物理学研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.10773002 and 10875012);supported by the Fundamental Research Funds for the Central Universities(Grant No.105116)

摘　　要：Abstract We use the recently released data of lookback time （LT）-redshift relation, the cosmic microwave background shift parameter and the baryon acoustic oscillation measurements to constrain cosmological parameters of f（R） gravity in the Palatini formalism by considering the f（R） form of type（a）f（R） = R -β/Rn and （b）f（R） = R ＋ αIn R - β. Under the assumption of a Friedmann-Robertson-Walker universe, we achieved the best fitting results of the free parameters （Ωm0, n） for （a） and （Ωm0, α） for （b）. We find that current LT data can provide interesting and effective constraints on gravity models. Compared with other data, the LT constraints favor a smaller value of the non-relativistic matter energy density.Abstract We use the recently released data of lookback time （LT）-redshift relation, the cosmic microwave background shift parameter and the baryon acoustic oscillation measurements to constrain cosmological parameters of f（R） gravity in the Palatini formalism by considering the f（R） form of type（a）f（R） = R -β/Rn and （b）f（R） = R ＋ αIn R - β. Under the assumption of a Friedmann-Robertson-Walker universe, we achieved the best fitting results of the free parameters （Ωm0, n） for （a） and （Ωm0, α） for （b）. We find that current LT data can provide interesting and effective constraints on gravity models. Compared with other data, the LT constraints favor a smaller value of the non-relativistic matter energy density.

关 键 词：cosmology： cosmic microwave background 

分 类 号：P223[天文地球—大地测量学与测量工程] P159[天文地球—测绘科学与技术]