QUANTIFYING DISCORDANCE IN THE 2015 PLANCK CMB SPECTRUM

By G. Addison, Y. Huang, D. Watts, C. Bennett, Mark Halpern, Gary F. Hinshaw, J. Weiland. 2015

193 citations recorded by the source corpus.

We examine the internal consistency of the Planck 2015 cosmic microwave background (CMB) temperature anisotropy power spectrum. We show that tension exists between cosmological constant cold dark matter ( Λ CDM ?> ) model parameters inferred from multipoles ℓ < 1000 ?> (roughly those accessible to Wilkinson Microwave Anisotropy Probe), and from ℓ ≥ 1000 ?> , particularly the CDM density, &OHgr; c h 2 ?> , which is discrepant at 2.5 &sgr; ?> for a Planck -motivated prior on the optical depth, τ = 0.07 ± 0.02 ?> . We find some parameter tensions to be larger than previously reported because of inaccuracy in the code used by the Planck Collaboration to generate model spectra. The Planck ℓ ≥ 1000 ?> constraints are also in tension with low-redshift data sets, including Planck ’s own measurement of the CMB lensing power spectrum ( 2.4 &sgr; ?> ), and the most precise baryon acoustic oscillation scale determination ( 2.5 &sgr; ?> ). The Hubble constant predicted by Planck from ℓ ≥ 1000 ?> , H 0 = 64.1 ± 1.7 ?> km s − 1 ?> Mpc−1, disagrees with the most precise local distance ladder measurement of 73.0 ± 2.4 ?> km s − 1 ?> Mpc−1 at the 3.0 &sgr; ?> level, while the Planck value from ℓ < 1000 ?> , 69.7 ± 1.7 ?> km s − 1 ?> Mpc−1, is consistent within 1 &sgr; ?> . A discrepancy between the Planck and South Pole Telescope high-multipole CMB spectra disfavors interpreting these tensions as evidence for new physics. We conclude that the parameters from the Planck high-multipole spectrum probably differ from the underlying values due to either an unlikely statistical fluctuation or unaccounted-for systematics persisting in the Planck data.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/19dc6add31539bc31d5235626f0fb20883b393dc

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Citations in the corpus

A 2.4% DETERMINATION OF THE LOCAL VALUE OF THE HUBBLE CONSTANT (2016, methodology): “Addison et al. (2015) has reported a parallel 2.5σ tension (size and significance) internally within the Planck data based on H0 parameters determined from multipoles with l<1000 and l>1000, with the two halves of the data producing H0=69.7±1.7 and 64.1±1.7 km s−1Mpc−1, respectively.”
Elucidating ΛCDM: Impact of Baryon Acoustic Oscillation Measurements on the Hubble Constant Discrepancy (2017, methodology): “In the full ΛCDM model space, the tension is not significant (1.8σ for the assumptions used by Addison et al. 2016; see also Planck Collaboration Int.”
Measuring Dark Energy Properties with Photometrically Classified Pan-STARRS Supernovae. II. Cosmological Parameters (2017, background): “The difference could be due to systematic uncertainties in one or both datasets (e.g. Addison et al. 2016), >3 neutrino species, non-Λ dark energy, or more exotic phenomena.”
Alleviating the H0 and σ8 anomalies with a decaying dark matter model (2019, background): “Although systematic causes for these discrepancies cannot entirely be ruled out, numerous potential systematics have been investigated and exonerated over the years while the tensions have persisted and worsened [7, 10, 15–20].”
The trouble with H0 (2016, methodology): “In the other cases, the tension is significant, except for the analysis of Planck 2015 temperature power spectrum limited to ` ≥ 1000 [25].”
Measurements of the Temperature and E-mode Polarization of the CMB from 500 Square Degrees of SPTpol Data (2017, background): “…data with different ` splits have found that including high-` (>∼ 800) measurements from Planck cause shifts in the derived cosmological parameters (Addison et al. 2016; Planck Collaboration et al. 2016d), though in a different direction in Ωch 2, H0, and σ8 than we find in this work with…”
A buyer’s guide to the Hubble constant (2021, methodology): “Addison et al. (2016) find that Alens is equivalent to a drift of cosmological parameters with different scales in the CMB.”