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Title: The phase-space structure of nearby dark matter as constrained by the SDSS

Abstract

Previous studies using numerical simulations have demonstrated that the shape of the cosmic web can be described by studying the Lagrangian displacement field. We extend these analyses, showing that it is now possible to perform a Lagrangian description of cosmic structure in the nearby Universe based on large-scale structure observations. Building upon recent Bayesian large-scale inference of initial conditions, we present a cosmographic analysis of the dark matter distribution and its evolution, referred to as the dark matter phase-space sheet, in the nearby universe as probed by the Sloan Digital Sky Survey main galaxy sample. We consider its stretchings and foldings using a tetrahedral tessellation of the Lagrangian lattice. The method provides extremely accurate estimates of nearby density and velocity fields, even in regions of low galaxy density. It also measures the number of matter streams, and the deformation and parity reversals of fluid elements, which were previously thought inaccessible using observations. We illustrate the approach by showing the phase-space structure of known objects of the nearby Universe such as the Sloan Great Wall, the Coma cluster and the Boötes void. We dissect cosmic structures into four distinct components (voids, sheets, filaments, and clusters), using the Lagrangian classifiers DIVA, ORIGAMI,more » and a new scheme which we introduce and call LICH. Because these classifiers use information other than the sheer local density, identified structures explicitly carry physical information about their formation history. Accessing the phase-space structure of dark matter in galaxy surveys opens the way for new confrontations of observational data and theoretical models. We have made our data products publicly available.« less

Authors:
;  [1];  [2]; ;  [3]
  1. Institute of Cosmology and Gravitation (ICG), University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth PO1 3FX (United Kingdom)
  2. Excellence Cluster Universe, Technische Universität München, Boltzmannstrasse 2, D-85748 Garching (Germany)
  3. Institut d'Astrophysique de Paris (IAP), UMR 7095, CNRS – UPMC Université Paris 6, Sorbonne Universités, 98bis boulevard Arago, F-75014 Paris (France)
Publication Date:
OSTI Identifier:
22676136
Resource Type:
Journal Article
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2017; Journal Issue: 06; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPUTERIZED SIMULATION; COSMOLOGICAL MODELS; DEFORMATION; DENSITY; DISTRIBUTION; GALAXIES; LAGRANGIAN FUNCTION; NONLUMINOUS MATTER; PARITY; PHASE SPACE; STREAMS; UNIVERSE; VELOCITY

Citation Formats

Leclercq, Florent, Percival, Will, Jasche, Jens, Lavaux, Guilhem, and Wandelt, Benjamin. The phase-space structure of nearby dark matter as constrained by the SDSS. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/06/049.
Leclercq, Florent, Percival, Will, Jasche, Jens, Lavaux, Guilhem, & Wandelt, Benjamin. The phase-space structure of nearby dark matter as constrained by the SDSS. United States. doi:10.1088/1475-7516/2017/06/049.
Leclercq, Florent, Percival, Will, Jasche, Jens, Lavaux, Guilhem, and Wandelt, Benjamin. Thu . "The phase-space structure of nearby dark matter as constrained by the SDSS". United States. doi:10.1088/1475-7516/2017/06/049.
@article{osti_22676136,
title = {The phase-space structure of nearby dark matter as constrained by the SDSS},
author = {Leclercq, Florent and Percival, Will and Jasche, Jens and Lavaux, Guilhem and Wandelt, Benjamin},
abstractNote = {Previous studies using numerical simulations have demonstrated that the shape of the cosmic web can be described by studying the Lagrangian displacement field. We extend these analyses, showing that it is now possible to perform a Lagrangian description of cosmic structure in the nearby Universe based on large-scale structure observations. Building upon recent Bayesian large-scale inference of initial conditions, we present a cosmographic analysis of the dark matter distribution and its evolution, referred to as the dark matter phase-space sheet, in the nearby universe as probed by the Sloan Digital Sky Survey main galaxy sample. We consider its stretchings and foldings using a tetrahedral tessellation of the Lagrangian lattice. The method provides extremely accurate estimates of nearby density and velocity fields, even in regions of low galaxy density. It also measures the number of matter streams, and the deformation and parity reversals of fluid elements, which were previously thought inaccessible using observations. We illustrate the approach by showing the phase-space structure of known objects of the nearby Universe such as the Sloan Great Wall, the Coma cluster and the Boötes void. We dissect cosmic structures into four distinct components (voids, sheets, filaments, and clusters), using the Lagrangian classifiers DIVA, ORIGAMI, and a new scheme which we introduce and call LICH. Because these classifiers use information other than the sheer local density, identified structures explicitly carry physical information about their formation history. Accessing the phase-space structure of dark matter in galaxy surveys opens the way for new confrontations of observational data and theoretical models. We have made our data products publicly available.},
doi = {10.1088/1475-7516/2017/06/049},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {1475-7516},
number = 06,
volume = 2017,
place = {United States},
year = {2017},
month = {6}
}