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arXiv · 2011.02858

Running Hubble Tension and a H0 Diagnostic

Chethan Krishnan·Eoin Ó Colgáin·M. M. Sheikh-Jabbari·Tao Yang
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Abstract

Hubble tension is routinely presented as a mismatch between the Hubble constant $H_0$ determined locally and a value inferred from the flat $\Lambda$CDM cosmology. In essence, the tension boils down to a disagreement between two numbers. Here, assuming the tension is cosmological in origin, we predict that within flat $\Lambda$CDM there should be other inferred values of $H_0$, and that a "running of $H_0$ with redshift" can be expected. These additional determinations of $H_0$ may be traced to a difference between the effective equation of state (EoS) of the Universe within the Friedmann-Lema\^itre-Robertson-Walker (FLRW) cosmology framework and the current standard model. We introduce a diagnostic that flags such a running of $H_0$.

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Chethan Krishnan, Eoin Ó Colgáin, M. M. Sheikh-Jabbari, Tao Yang. 2020-11-04. Running Hubble Tension and a H0 Diagnostic. https://doi.org/10.1103/physrevd.103.103509

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