Local probes strongly favor $Λ$CDM against power-law and $R_h=ct$ universe

Abstract

We constrain three cosmological models, i.e. the concordance cold dark matter plus a cosmological constant ($Λ$CDM) model, Power-law (PL) model, and $R_h=ct$ model using the available local probes, which includes the JLA compilation of type-Ia supernovae (SNe Ia), the direct measurement of Hubble constant (H(z)), and the baryon acoustic oscillations (BAO). For $Λ$CDM model, we consider two different cases, i.e. zero and non-zero spatial curvature. We find that by using the JLA alone, it is indistinguishable between $Λ$CDM and PL models, but the $R_h=ct$ model is strongly disfavored. If we combine JLA+H(z), the $Λ$CDM model is strongly favored against the other two models. The combination of all the three datasets also supports $Λ$CDM as the best model. We also use the low-redshift ($z<0.2$) data to constrain the deceleration parameter using cosmography method, and find that only the $Λ$CDM model is consistent with cosmography. However, there is no strong evidence to distinguish between flat and non-flat $Λ$CDM models by using the local data alone.

8 pages, 3 tables