English

Reference frame dependence of the local measurement of the Hubble constant

General Relativity and Quantum Cosmology 2020-06-01 v2 Cosmology and Nongalactic Astrophysics

Abstract

Observations recently suggest 4.4σ4.4\sigma discrepancy between Hubble constant measured locally and that inferred from cosmic microwave background in standard cosmology. Either standard cosmology or local measurement might expect something new. We investigate the possibility that the value of Hubble constants might be affected by observers' motional status in the local measurement. Using adapted coordinate for geodesic observers in FLRW space-time and constraints inferred from observation of cosmic shear, we find that the motional status of reference frame could contribute to about 1.1±0.3%1.1 \pm 0.3\% discrepancy of these Hubble constants. Namely, the difference is ΔH0=0.81±0.22\Delta H_0= 0.81\pm0.22 km s1^{-1} Mpc1^{-1}, if the locally measured Hubble constant is 74 74 km s1^{-1} Mpc1^{-1}. This effect seems not negligible as an uncertainty for local measurement of Hubble constant

Keywords

Cite

@article{arxiv.1909.13252,
  title  = {Reference frame dependence of the local measurement of the Hubble constant},
  author = {Zhe Chang and Qing-Hua Zhu},
  journal= {arXiv preprint arXiv:1909.13252},
  year   = {2020}
}

Comments

v1: 12 pages; v2: 19 pages, 2 figures. A revised version for publishing in PRD