The local and distant Universe: stellar ages and $H_0$

Abstract

The ages of the oldest stellar objects in our galaxy provide an independent test of the current cosmological model as they give a lower limit to the age of the Universe. Recent accurate parallaxes by the Gaia space mission, accurate measurements of the metallicity of stars, via individual elemental abundances, and advances in the modelling of stellar evolution, provide new, higher-precision age estimates of the oldest stellar populations in the galaxy: globular clusters and very-low-metallicity stars. The constraints on the age of the Universe, $t_U$, so obtained are determined from the local Universe and at late time. It is well known that local and early-Universe determinations of another cosmological parameter closely related to the age of the Universe, the Hubble constant $H_0$, show a $\gtrsim 3\sigma$ tension. In the standard cosmological model, $\Lambda$CDM, $t_U$ and $H_0$ are related by the matter density parameter ${\Omega }_{m,0}$. We propose to combine local $t_U$ constraints with late-time ${\Omega }_{m,0}$ estimates in a $\Lambda$CDM framework, to obtain a low-redshift $H_0$ determination that does not rely on early Universe physics. A proof-of-principle of this approach with current data gives $H_0=71\pm 2.8$ ($H_0=69.3\pm 2.7$) km s${}^{-1}$ Mpc${}^{-1}$ from globular clusters (very-low-metallicity stars) with excellent prospects for improved constraints in the near future.

Matches published version in JCAP; references added, no other changes

References in corpus (11)

• A gravitational-wave standard siren measurement of the Hubble constant
• Raising the bar: new constraints on the Hubble parameter with cosmic chronometers at z$\sim$2
• The trouble with $H_0$
• The effects of He I 10830 on helium abundance determinations
• Baryon acoustic oscillations from the complete SDSS-III Ly$\alpha$-quasar cross-correlation function at $z=2.4$
• HD 140283: A Star in the Solar Neighborhood that Formed Shortly After the Big Bang
• Standard rulers, candles, and clocks from the low-redshift Universe
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: tomographic BAO analysis of DR12 combined sample in Fourier space
• The ACS Survey of Galactic Globular Clusters XIV: Bayesian Single-Population Analysis of 69 Globular Clusters
• Globular clusters with Gaia
• The Hubble constant and new discoveries in cosmology

Cited by in corpus (22)

• Planck evidence for a closed Universe and a possible crisis for cosmology
• Seven hints that early-time new physics alone is not sufficient to solve the Hubble tension
• Eppur è piatto? The cosmic chronometer take on spatial curvature and cosmic concordance
• Dark energy in light of the early JWST observations: case for a negative cosmological constant?
• A new measurement of the expansion history of the Universe at z=1.26 with cosmic chronometers in VANDELS
• Negative cosmological constant in the dark energy sector: tests from JWST photometric and spectroscopic observations of high-redshift galaxies
• Multidimensionality of the Hubble tension: the roles of ${\Omega }_m$ and ${\omega }_c$
• Exploring the Hubble Tension and Spatial Curvature from the Ages of Old Astrophysical Objects
• Questioning the $H_0$ tension via the look-back time
• Cascading Dark Energy
• A critical discussion on the $H_0$ tension
• Model-independent cosmological inference after the DESI DR2 data with improved inverse distance ladder
• A generalized mass-to-horizon relation: a new global approach to entropic cosmologies and its connection to $\Lambda$CDM
• Uranium Abundances and Ages of $R$-process Enhanced Stars with Novel U II Lines
• Globular clusters as cosmic clocks: new cosmological hints from their integrated light
• The oldest Milky Way stars: New constraints on the age of the Universe and the Hubble constant
• Time to Sparkler. Accurate ages of lensed globular clusters at $z=1.4$ with JWST photometry
• Missing Components in ΛCDM from DESI Y1 BAO Measurements: Insights from Redshift Remapping
• Impact of Large-Scale Structure along Line-of-Sight on Time-Delay Cosmography
• Lifetimes of light stringy states
• A Spectrum of Cosmological Rips and Their Observational Signatures
• Testing the CCC+TL cosmology with cosmic-chronometer measurements of the Hubble parameter