On the use of galaxies as clocks and the universal expansion

Abstract

We set out to rederive the 8 Hubble parameter values obtained from estimated relative galaxy ages by Simon et al. [Physical Review D, 71, 123001 (2005)]. We find that to obtain the level of precision claimed in $H(z)$, unrealistically small galaxy age uncertainties have to be assumed. Also, some parameter values will be correlated. In our analysis we find that the uncertainties in the Hubble parameter values are significantly larger when 8 independent $H(z)$ are obtained using Monte Carlo sampling. Smaller uncertainties can be obtained using Gaussian processes, but at the cost of strongly correlated results. We do not obtain any useful constraints on the Hubble parameter from the galaxy data employed.

8 pages, 10 figures. Matches version published in MNRAS

References in corpus (6)

• Raising the bar: new constraints on the Hubble parameter with cosmic chronometers at z$\sim$2
• Gaussian Process Cosmography
• Measurements of $H_0$ and reconstruction of the dark energy properties from a model-independent joint analysis
• Improved constraints on the dark energy equation of state using Gaussian processes
• Testing the equation of state for viscous dark energy
• A look at the Hubble speed from first principles

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