Concordance Cosmology?

Abstract

We propose a new intuitive metric for evaluating the tension between two experiments, and apply it to several data sets. While our metric is non-optimal, if evidence of tension is detected, this evidence is robust and easy to interpret. Assuming a flat $\Lambda$CDM cosmological model, we find that there is a modest $2.2\sigma$ tension between the DES Year 1 results and the $Planck$ measurements of the Cosmic Microwave Background (CMB). This tension is driven by the difference between the amount of structure observed in the late-time Universe and that predicted from fitting the $Planck$ data, and appears to be unrelated to the tension between $Planck$ and local esitmates of the Hubble rate. In particular, combining DES, Baryon Acoustic Oscillations (BAO), Big-Bang Nucleosynthesis (BBN), and supernovae (SNe) measurements recovers a Hubble constant and sound horizon consistent with $Planck$, and in tension with local distance-ladder measurements. If the tension between these various data sets persists, it is likely that reconciling $all$ current data will require breaking the flat $\Lambda$CDM model in at least two different ways: one involving new physics in the early Universe, and one involving new late-time Universe physics.

arXiv comment8 pages. 5 figures

References in corpus (21)

• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample
• MultiNest: an efficient and robust Bayesian inference tool for cosmology and particle physics
• The Complete Light-curve Sample of Spectroscopically Confirmed Type Ia Supernovae from Pan-STARRS1 and Cosmological Constraints from The Combined Pantheon Sample
• The 6dF Galaxy Survey: Baryon Acoustic Oscillations and the Local Hubble Constant
• The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
• The Temperature of the Cosmic Microwave Background
• Dark Energy Survey Year 1 Results: Cosmological Constraints from Cosmic Shear
• Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data
• CosmoSIS: modular cosmological parameter estimation
• KiDS+GAMA: Cosmology constraints from a joint analysis of cosmic shear, galaxy-galaxy lensing and angular clustering
• Sounds Discordant: Classical Distance Ladder & $\Lambda$CDM -based Determinations of the Cosmological Sound Horizon
• Concordance and Discordance in Cosmology
• redMaGiC: Selecting Luminous Red Galaxies from the DES Science Verification Data
• Dark Energy Survey Year 1 Results: Weak Lensing Shape Catalogues
• Dark Energy Survey Year 1 Results: Galaxy clustering for combined probes
• The primordial deuterium abundance of the most metal-poor damped Lyman-alpha system
• Dark Energy Survey Year 1 Results: Multi-Probe Methodology and Simulated Likelihood Analyses
• Dark Energy Survey Year 1 Results: Galaxy-Galaxy Lensing
• Planck confronts large scale structure: methods to quantify discordance
• Quantifying Concordance in Cosmology
• A Bayesian quantification of consistency in correlated datasets

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• KiDS & Euclid: Cosmological implications of a pseudo angular power spectrum analysis of KiDS-1000 cosmic shear tomography
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