The Maximum Angular-Diameter Distance in Cosmology

Abstract

Unlike other observational signatures in cosmology, the angular-diameter distance d_A(z) uniquely reaches a maximum (at z_max) and then shrinks to zero towards the big bang. The location of this turning point depends sensitively on the model, but has been difficult to measure. In this paper, we estimate and use z_max inferred from quasar cores: (1) by employing a sample of 140 objects yielding a much reduced dispersion due to pre-constrained limits on their spectral index and luminosity, (2) by reconstructing d_A(z) using Gaussian processes, and (3) comparing the predictions of seven different cosmologies and showing that the measured value of z_max can effectively discriminate between them. We find that z_max=1.70 +\- 0.20---an important new probe of the Universe's geometry. The most strongly favoured model is R_h=ct, followed by Planck LCDM. Several others, including Milne, Einstein-de Sitter and Static tired light are strongly rejected. According to these results, the R_h=ct universe, which predicts z_max=1.718, has a ~92.8% probability of being the correct cosmology. For consistency, we also carry out model selection based on d_A(z) itself. This test confirms that R_h=ct and Planck LCDM are among the few models that account for angular-size data better than those that are disfavoured by z_max. The d_A(z) comparison, however, is less discerning than that with z_max, due to the additional free parameter, H_0. We find that H_0=63.4 +\- 1.2 km/s/Mpc for R_h=ct, and 69.9 +\- 1.5 km/s/Mpc for LCDM. Both are consistent with previously measured values in each model, though they differ from each other by over 4 sigma. In contrast, model selection based on z_max is independent of H_0.

arXiv comment10 pages, 5 figures, 2 tables. Matches final, published version in MNRAS

References in corpus (46)

• Milky Way Cepheid Standards for Measuring Cosmic Distances and Application to Gaia DR2: Implications for the Hubble Constant
• Reconstruction of dark energy and expansion dynamics using Gaussian processes
• The R_h = ct Universe
• Nonparametric Dark Energy Reconstruction from Supernova Data
• Evidence for a ~300 Mpc Scale Under-density in the Local Galaxy Distribution
• Consequences on variable Lambda-models from distant Type Ia supernovae and compact radio sources
• The Cosmic Horizon
• The International Deep Planet Survey II: The frequency of directly imaged giant exoplanets with stellar mass
• Ultra-compact structure in intermediate-luminosity radio quasars: building a sample of standard cosmological rulers and improving the dark energy constraints up to $z\sim 3$
• Cosmic Chronometers in the R_h=ct Universe
• Cardassian Expansion: Constraints from Compact Radio Source Angular Size versus Redshift Data
• Measuring the speed of light with ultra-compact radio quasars
• Cosmological Constraints from Compact Radio Source Angular Size versus Redshift Data
• Dark energy and the angular size - redshift diagram for milliarcsecond radio sources
• Constraining Omega_0 With The Angular-Size Redshift Relation Of Double-Lobed Quasars In The FIRST Survey
• Radio Galaxy Redshift-Angular Size Data Constraints on Dark Energy
• The Linear Growth of Structure in the R_h=ct Universe
• Physical Basis for the Symmetries in the Friedmann-Robertson-Walker Metric
• Deceleration without dark matter
• The Zero Active Mass Condition in Friedmann-Robertson-Walker Cosmologies
• The XMM--NEWTON Omega Project: II.Cosmological implications from the high redshift L-T relation of X-ray clusters
• Model Selection Using Cosmic Chronometers with Gaussian Processes
• On Recent Claims Concerning the R_h=ct Universe
• A Test of Cosmological Models using high-z Measurements of H(z)
• Reconstruction of the HII Galaxy Hubble Diagram using Gaussian Processes
• Exploring the properties of milliarcsecond radio sources
• Tight Cosmological Constraints from the Angular-Size/Redshift Relation for Ultra-Compact Radio Sources
• Angular Correlation of the CMB in the R_h=ct Universe
• The angular size - redshift relation in power-law cosmologies
• Legacy data and cosmological constraints from the angular-size/redshift relation for ultra-compact radio sources
• Clustering, Angular Size and Dark Energy
• Proper Size of the Visible Universe in FRW Metrics with Constant Spacetime Curvature
• Angular Diameters as a Probe of a Cosmological Constant and $\Omega$
• Impact of a locally measured H_0 on the interpretation of cosmic chronometer data
• Definitive Test of the R_h=ct Universe Using Redshift Drift
• Redshift of photons penetrating a hot plasma
• Hubble trouble or Hubble bubble?
• A Curious Explanation of Some Cosmological Phenomena
• Analyzing H(z) Data using Two-point Diagnostics
• Peculiar Hubble Flows in Our Local Universe
• Cosmological Tests With Strong Gravitational Lenses using Gaussian Processes
• Expanding space, quasars and St. Augustine's fireworks
• Is there a standard measuring rod in the Universe?
• A Two-point Diagnostic for the HII Galaxy Hubble Diagram
• A Cosmological Solution to the Impossibly Early Galaxy Problem
• Unseen Progenitors of Luminous High-z Quasars in the R_h=ct Universe

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