Doux, C., et al. DES Collaboration ; Beyond ΛCDM, physics or systematic errors may cause subsets of a cosmological data set to appear inconsistent when analysed assuming ΛCDM. We present an application of internal consistency tests to measurements from the Dark Energy Survey Year 1 (DES Y1) joint probes analysis. Our analysis relies on computing the posterior predictive distribution (PPD) for these data under the assumption of ΛCDM. We find that the DES Y1 data have an acceptable goodness of fit to ΛCDM, with a probability of finding a worse fit by random chance of p = 0.046. Using numerical PPD tests, supplemented by graphical checks, we show that most of the data vector appears completely consistent with expectations, although we observe a small tension between large- and small-scale measurements. A small part (roughly 1.5 per cent) of the data vector shows an unusually large departure from expectations; excluding this part of the data has negligible impact on cosmological constraints, but does significantly improve the p-value to 0.10. The methodology developed here will be applied to test the consistency of DES Year 3 joint probes data sets. ; Based, in part, on observations at Cerro Tololo Inter-American Observatory at NSF's NOIRLab (NOIRLab Prop. ID 2012B-0001; PI: J. Frieman), which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. The DES data management system is supported by the National Science Foundation under grant numbers AST-1138766 and AST-1536171. The DES participants from Spanish institutions are partially supported by MICINN under grants ESP2017-89838, PGC2018-094773, PGC2018-102021, SEV-2016-0588, SEV-2016-0597, and MDM-2015-0509, some of which include ERDF funds from the European Union. IFAE is partially funded by the CERCA program of the Generalitat de Catalunya. Research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Program (FP7/2007-2013) including ERC grant agreements 240672, 291329, and 306478. We acknowledge support from the Brazilian Instituto Nacional de Ciência e Tecnologia (INCT) do e-Universo (CNPq grant 465376/2014-2). This manuscript has been authored by Fermi Research Alliance, LLC under contract no. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics.
20 pages, 18 figures.-- et al. ; Baryon Acoustic Oscillations (BAOs) provide a "standard ruler" of known physical length, making it one of the most promising probes of the nature of dark energy (DE). The detection of BAOs as an excess of power in the galaxy distribution at a certain scale requires measuring galaxy positions and redshifts. "Transversal" (or "angular") BAOs measure the angular size of this scale projected in the sky and provide information about the angular distance. "Line-of-sight" (or "radial") BAOs require very precise redshifts, but provide a direct measurement of the Hubble parameter at different redshifts, a more sensitive probe of DE. The main goal of this paper is to show that it is possible to obtain photometric redshifts with enough precision (σz) to measure BAOs along the line of sight. There is a fundamental limitation as to how much one can improve the BAO measurement by reducing σz . We show that σz ~ 0.003(1 + z) is sufficient: a much better precision will produce an oversampling of the BAO peak without a significant improvement on its detection, while a much worse precision will result in the effective loss of the radial information. This precision in redshift can be achieved for bright, red galaxies, featuring a prominent 4000 Å break, by using a filter system comprising about 40 filters, each with a width close to 100 Å, covering the wavelength range from ~4000 to ~8000 Å, supplemented by two broad-band filters similar to the Sloan Digital Sky Survey u and z bands. We describe the practical implementation of this idea, a new galaxy survey project, Physics of the Accelerating Universe (PAU): http://www.ice.cat/pau, to be carried out with a telescope/camera combination with an etendue about 20 m2 deg2, equivalent to a 2 m telescope equipped with a 6 deg2 field of view camera, and covering 8000 deg2 in the sky in four years. We expect to measure positions and redshifts for over 14 million red, early-type galaxies with L > L* and i(AB) ~ 10–3 Mpc–3 h3 galaxies within the 9 Gpc3 h–3 volume to be sampled by our survey, ensuring that the error in the determination of the BAO scale is not limited by shot noise. By itself, such a survey will deliver precisions of order 5% in the dark-energy equation of state parameter w, if assumed constant, and can determine its time derivative when combined with future cosmic microwave background measurements. In addition, PAU will yield high-quality redshift and low-resolution spectroscopy for hundreds of millions of other galaxies, including a very significant high-redshift population. The data set produced by this survey will have a unique legacy value, allowing a wide range of astrophysical studies. ; This work was carried out in the framework of the PAU Consolider Collaboration, supported in part by the Spanish Ministry of Education and Science (MEC) through the Consolider Ingenio-2010 program, under project CSD2007-00060 "Physics of the Accelerating Universe (PAU)". Additional support comes from the Barcelona Supercomputer Center, as well as from the European Commission, the Spanish High Council for Scientific Research (CSIC), and the regional governments of Andalusia, Aragon, Catalonia, Madrid, and Valencia. ; Peer reviewed
Mattia, A. de, et al. ; We analyse the large-scale clustering in Fourier space of emission line galaxies (ELG) from the Data Release 16 of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey. The ELG sample contains 173 736 galaxies covering 1170 deg2 in the redshift range 0.6 < z < 1.1. We perform a BAO measurement from the post-reconstruction power spectrum monopole, and study redshift space distortions (RSD) in the first three even multipoles. Photometric variations yield fluctuations of both the angular and radial survey selection functions. Those are directly inferred from data, imposing integral constraints which we model consistently. The full data set has only a weak preference for a BAO feature (1.4σ). At the effective redshift zeff = 0.845 we measure D_{\rm V}(z_{\rm eff})/r_{\rm drag} = 18.33_{-0.62}^{+0.57}, with DV the volume-averaged distance and rdrag the comoving sound horizon at the drag epoch. In combination with the RSD measurement, at zeff = 0.85 we find f\sigma _8(z_{\rm eff}) = 0.289_{-0.096}^{+0.085}, with f the growth rate of structure and σ8 the normalization of the linear power spectrum, D_{\rm H}(z_{\rm eff})/r_{\rm drag} = 20.0_{-2.2}^{+2.4} and DM(zeff)/rdrag = 19.17 ± 0.99 with DH and DM the Hubble and comoving angular distances, respectively. These results are in agreement with those obtained in configuration space, thus allowing a consensus measurement of fσ8(zeff) = 0.315 ± 0.095, D_{\rm H}(z_{\rm eff})/r_{\rm drag} = 19.6_{-2.1}^{+2.2} and DM(zeff)/rdrag = 19.5 ± 1.0. This measurement is consistent with a flat ΛCDM model with Planck parameters. ; AdM acknowledges support from the P2IO LabEx (ANR-10-LABX-0038) in the framework 'Investissements d'Avenir' (ANR-11-IDEX-0003-01) managed by the Agence Nationale de la Recherche (ANR, France). This work was supported by the ANR eBOSS project (ANR-16-CE31-0021) of the French National Research Agency. AR acknowledges support from the ERC advanced grant LIDA. AR, CZ, and AT acknowledge support from the SNF grant 200020_175751. AJR is grateful for support from the Ohio State University Center for Cosmology and Particle Physics. SA is supported by the European Research Council through the COSFORM Research Grant (#670193). SA was supported by the MICUES project, funded by the European Union's Horizon 2020 research programme under the Marie Sklodowska-Curie Grant Agreement No. 713366 (InterTalentum UAM). VGP acknowledges support from the European Union's Horizon 2020 research and innovation programme (ERC grant #769130). YW and GBZ are supported by NSFC Grants 11925303, 11720101004, 11673025 and 11890691. G-BZ is also supported by the National Key Basic Research and Development Program of China (No. 2018YFA0404503), and a grant of CAS Interdisciplinary Innovation Team. YW is also supported by the Nebula Talents Program of NAOC. GR acknowledges support from the National Research Foundation of Korea (NRF) through Grant Nos. 2017R1E1A1A01077508 and 2020R1A2C1005655 funded by the Korean Ministry of Education, Science and Technology (MoEST), and from the faculty research fund of Sejong University.
The Large-Scale Structure of Inductive Inference investigates the relations of inductive support on the large scale, among the totality of facts comprising a science or science in general. These relations form a massively entangled, non-hierarchical structure which is discovered by making hypotheses provisionally that are later supported by facts drawn from the entirety of the science. What results is a benignly circular, self-supporting inductive structure in which universal rules are not employed, the classical Humean problem cannot be formulated and analogous regress arguments fail.
The earlier volume, The Material Theory of Induction, proposed that individual inductive inferences are warranted not by universal rules but by facts particular to each context. This book now investigates how the totality of these inductive inferences interact in a mature science. Each fact that warrants an individual inductive inference is in turn supported inductively by other facts. Numerous case studies in the history of science support, and illustrate further, those claims. This is a novel, thoroughly researched, and sustained remedy to the enduring failures of formal approaches to inductive inference. With The Large-Scale Structure of Inductive Inference, author John D. Norton presents a novel, thoroughly researched, and sustained remedy to the enduring failures of formal approaches of inductive inference.
DES Collaboration: et al. ; Obtaining accurate distributions of galaxy redshifts is a critical aspect of weak lensing cosmology experiments. One of the methods used to estimate and validate redshift distributions is to apply weights to a spectroscopic sample, so that their weighted photometry distribution matches the target sample. In this work, we estimate the selection bias in redshift that is introduced in this procedure. We do so by simulating the process of assembling a spectroscopic sample (including observer-assigned confidence flags) and highlight the impacts of spectroscopic target selection and redshift failures. We use the first year (Y1) weak lensing analysis in Dark Energy Survey (DES) as an example data set but the implications generalize to all similar weak lensing surveys. We find that using colour cuts that are not available to the weak lensing galaxies can introduce biases of up to Δz ∼ 0.04 in the weighted mean redshift of different redshift intervals (Δz ∼ 0.015 in the case most relevant to DES). To assess the impact of incompleteness in spectroscopic samples, we select only objects with high observer-defined confidence flags and compare the weighted mean redshift with the true mean. We find that the mean redshift of the DES Y1 weak lensing sample is typically biased at the Δz = 0.005−0.05 level after the weighting is applied. The bias we uncover can have either sign, depending on the samples and redshift interval considered. For the highest redshift bin, the bias is larger than the uncertainties in the other DES Y1 redshift calibration methods, justifying the decision of not using this method for the redshift estimations. We discuss several methods to mitigate this bias. ; The DES data management system is supported by the National Science Foundation under grants AST-1138766 and AST-1536171. The DES participants from Spanish institutions are partially supported by MINECO under grants AYA2015-71825, ESP2015-66861, FPA2015-68048, SEV-2016-0588, SEV-2016-0597, and MDM2015-0509, some of which include ERDF funds from the European Union. IFAE is partially funded by the CERCA program of the Generalitat de Catalunya. Research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Program (FP7/2007-2013) including ERC grant agreements 240672, 291329, and 306478. We acknowledge support from the Brazilian Instituto Nacional de Ciencia e Tecnologia (INCT) e-Universe (CNPq grant 465376/2014-2). ; Peer reviewed
DES Collaboration: et al. ; We construct and validate the selection function of the MARD-Y3 galaxy cluster sample. This sample was selected through optical follow-up of the 2nd ROSAT faint source catalogue with Dark Energy Survey year 3 data. The selection function is modelled by combining an empirically constructed X-ray selection function with an incompleteness model for the optical follow-up. We validate the joint selection function by testing the consistency of the constraints on the X-ray flux–mass and richness–mass scaling relation parameters derived from different sources of mass information: (1) cross-calibration using South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) clusters, (2) calibration using number counts in X-ray, in optical and in both X-ray and optical while marginalizing over cosmological parameters, and (3) other published analyses. We find that the constraints on the scaling relation from the number counts and SPT-SZ cross-calibration agree, indicating that our modelling of the selection function is adequate. Furthermore, we apply a largely cosmology independent method to validate selection functions via the computation of the probability of finding each cluster in the SPT-SZ sample in the MARD-Y3 sample and vice versa. This test reveals no clear evidence for MARD-Y3 contamination, SPT-SZ incompleteness or outlier fraction. Finally, we discuss the prospects of the techniques presented here to limit systematic selection effects in future cluster cosmological studies. ; The DES data management system is supported by the National Science Foundation under grant numbers AST-1138766 and AST-1536171. The DES participants from Spanish institutions are partially supported by MINECO under grants AYA2015- 71825, ESP2015-66861, FPA2015-68048, SEV-2016-0588, SEV2016-0597, and MDM-2015-0509, some of which include ERDF funds from the European Union. IFAE is partially funded by the CERCA program of the Generalitat de Catalunya. Research leading to these results has received funding from the European Research Council under the European Union 7th Framework Programme (FP7/2007-2013) including ERC grant agreements 240672, 291329, and 306478. We acknowledge support from the Brazilian Instituto Nacional de Ciencia e Tecnologia (INCT) e-Universe (CNPq grant 465376/2014-2). ; Peer reviewed
We construct a large, redshift-complete sample of distant galaxy clusters by correlating Sloan Digital Sky Survey Data Release 12 redshifts with clusters identified with the red-sequence Matched-filter Probabilistic Percolation (redMaPPer) algorithm. Our spectroscopic completeness is > 97 per cent for ≃ 7000 clusters within the redMaPPer selection limit, z=0.325, so that our cluster correlation functions aremuch more precise than earlierwork and not suppressed by uncertain photometric redshifts.We derive an accurate power-law mass-richness relation from the observed abundance with respect to the mass function from Millennium XXL (MXXL) simulations, adjusted to the Planck-weighted cosmology. The number density of clusters is found to decline by 20 per cent over the range 0.1 < z < 0.3, in good agreement with the evolution predicted by MXXL. Our projected 3D correlation function scales with richness, λ, rising from r = 14 h Mpc at λ ≃25 to r = 22 h Mpc at λ ≃ 60, with a gradient that matches MXXL when applying our mass-richness relation, whereas the observed amplitude of the correlation function at 〈z〉 = 0.24 exceeds the MXXL prediction by 20 per cent at the ≃2.5σ level. This tension cannot be blamed on spurious, randomly located clusters as this would reduce the correlation amplitude. Full consistency between the correlation function and the abundances is achievable for the pre-Planck values of σ = 0.9, Ω = 0.25 and h = 0.73, matching the improved distance ladder estimate of the Hubble constant. ; TJB is supported by IKERBASQUE, the Basque Foundation for Science. RL is supported by the Spanish Ministry of Economy and Competitiveness through research projects FIS2010-15492 and Consolider EPI CSD2010-00064, and the University of the Basque Country UPV/EHU under program UFI 11/55. PJ acknowledges financial support from the Basque Government grant BFI-2012-349. TJB, RL and PJ are also supported by the Basque Government grant for the GIC IT956-16 research group. REA acknowledges support from AYA2015-66211-C2-2. JMD acknowledges support of the projects AYA2015-64508-P (MINECO/FEDER, UE), AYA2012-39475-C02-01 and the consolider project CSD2010-00064 funded by the Ministerio de Economia y Competitividad. KU acknowledges partial support from the Ministry of Science and Technology of Taiwan (grants MOST 103-2112-M-001-030-MY3 and MOST 103-2112-M-001-003-MY3). Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation and the US Department of Energy Office of Science. ; Peer Reviewed
Acknowledgements. The Planck Collaboration acknowledges the support of: ESA; CNES and CNRS/INSU-IN2P3-INP (France); ASI, CNR, and INAF (Italy); NASA and DoE (USA); STFC and UKSA (UK); CSIC, MINECO, JA, and RES (Spain); Tekes, AoF, and CSC (Finland); DLR and MPG (Germany); CSA (Canada); DTU Space (Denmark); SER/SSO (Switzerland); RCN (Norway); SFI (Ireland); FCT/MCTES (Portugal); ERC and PRACE (EU). A description of the Planck Collaboration and a list of its members, indicating which technical or scientific activities they have been involved in, can be found at http://www.cosmos.esa.int/web/planck/ planck-collaboration. Some of the results in this paper have been derived using the HEALPix package. We acknowledge support from the Science and Technology Facilities Council [grant number ST/L000652/1]. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ ERC Grant Agreement No. [616170]. Part of this work was undertaken on the STFC DiRAC HPC Facilities at the University of Cambridge funded by UK BIS National E-infrastructure capital grants. ; We present the most significant measurement of the cosmic microwave background (CMB) lensing potential to date (at a level of 40σ), using temperature and polarization data from the Planck 2015 full-mission release. Using a polarization-only estimator, we detect lensing at a significance of 5σ. We cross-check the accuracy of our measurement using the wide frequency coverage and complementarity of the temperature and polarization measurements. Public products based on this measurement include an estimate of the lensing potential over approximately 70% of the sky, an estimate of the lensing potential power spectrum in bandpowers for the multipole range 40 ≤ L ≤ 400, and an associated likelihood for cosmological parameter constraints. We find good agreement between our measurement of the lensing potential power spectrum and that found in the ΛCDM model that best fits the Planck temperature and polarization power spectra. Using the lensing likelihood alone we obtain a percent-level measurement of the parameter combination σ8Ω0.25m = 0.591 ± 0.021. We combine our determination of the lensing potential with the E-mode polarization, also measured by Planck, to generate an estimate of the lensing B-mode. We show that this lensing B-mode estimate is correlated with the B-modes observed directly by Planck at the expected level and with a statistical significance of 10σ, confirming Planck's sensitivity to this known sky signal. We also correlate our lensing potential estimate with the large-scale temperature anisotropies, detecting a cross-correlation at the 3σ level, as expected because of dark energy in the concordance ΛCDM model. ; European Space Agency ; Centre National D'etudes Spatiales ; CNRS/INSU-IN2P3-INP (France) ; Italian Space Agency (ASI) ; Italian National Research Council ; Istituto Nazionale Astrofisica (INAF) ; National Aeronautics & Space Administration (NASA) ; United States Department of Energy (DOE) ; UKSA (UK) ; Consejo Superior de Investigaciones Cientificas (CSIC) ; MINECO (Spain) ; JA (Spain) ; RES (Spain) ; Finnish Funding Agency for Technology & Innovation (TEKES) ; AoF (Finland) ; CSC (Finland) ; Helmholtz Association ; German Aerospace Centre (DLR) ; Max Planck Society ; CSA (Canada) ; DTU Space (Denmark) ; SER/SSO (Switzerland) ; RCN (Norway) ; Science Foundation Ireland ; Portuguese Foundation for Science and Technology ; ERC (EU) ; European Union (EU) ; Science & Technology Facilities Council (STFC) ST/L000652/1 ; European Research Council (ERC) 616170 ; UK BIS National E-infrastructure capital grants ; Science & Technology Facilities Council (STFC) ST/L000768/1 ST/L000393/1 ST/L000636/1