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Concept

Cosmologie cyclique conforme

Publications associées (32)

Towards Efficient and Accurate Numerical Simulations of Galaxies using Task-based Parallelism and Application to Dwarf Galaxies

Loïc Hausammann

Numerical simulations are of a tremendous help to understand the growth of non-linear cosmological structures and how they lead to the formation of galaxies. In recent years, with the goal of improving their prediction power, new hydrodynamical techniques ...

EPFL2021

The GOGREEN survey: Internal dynamics of clusters of galaxies at redshift 0.9-1.4

Pascale Jablonka, Hung-Hsu Chan

Context. The study of galaxy cluster mass profiles (M(r)) provides constraints on the nature of dark matter and on physical processes affecting the mass distribution. The study of galaxy cluster velocity anisotropy profiles (beta (r)) informs the orbits of ...

EDP SCIENCES S A2021

The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Large-scale structure catalogues for cosmological analysis

Jean-Paul Richard Kneib, Cheng Zhao, Anand Stéphane Raichoor

We present large-scale structure catalogues from the completed extended Baryon Oscillation Spectroscopic Survey (eBOSS). Derived from Sloan Digital Sky Survey (SDSS) IV Data Release 16 (DR16), these catalogues provide the data samples, corrected for observ ...

OXFORD UNIV PRESS2020

H0LiCOW-XIII. A 2.4 per cent measurement of H-0 from lensed quasars: 5.3 sigma tension between early- and late-Universe probes

Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Vivien François Bonvin, Martin Raoul Robert Millon, Olga Tihhonova

We present a measurement of the Hubble constant (H-0) and other cosmological parameters from a joint analysis of six gravitationally lensed quasars with measured time delays. All lenses except the first are analysed blindly with respect to the cosmological ...

OXFORD UNIV PRESS2020

The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the luminous red galaxy sample from the anisotropic power spectrum between redshifts 0.6 and 1.0

Cheng Zhao, Anand Stéphane Raichoor, Amélie Tamone

We analyse the clustering of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey Data Release 16 luminous red galaxy sample (DR16 eBOSS LRG) in combination with the high redshift tail of the Sloan Digital Sky Survey III Baryon ...

OXFORD UNIV PRESS2020

The clustering of the SDSS-IV extended baryon oscillation spectroscopic survey DR16 luminous red galaxy and emission-line galaxy samples: cosmic distance and structure growth measurements using multiple tracers in configuration space

Jean-Paul Richard Kneib, Cheng Zhao, Anand Stéphane Raichoor, Amélie Tamone

We perform a multitracer analysis using the complete Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) DR16 luminous red galaxy (LRG) and the DR16 emission-line galaxy (ELG) samples in the configuration space, a ...

OXFORD UNIV PRESS2020

Controlling and leveraging small-scale information in tomographic galaxy-galaxy lensing

Jonathan Andrew Blazek

The tangential shear signal receives contributions from physical scales in the galaxy-matter correlation function well below the transverse scale at which it is measured. Since small scales are difficult to model, this non-locality has generally required s ...

OXFORD UNIV PRESS2020

Black hole metamorphosis and stabilization by memory burden

Sebastian Zell

Systems of enhanced memory capacity are subjected to a universal effect of memory burden, which suppresses their decay. In this paper, we study a prototype model to show that memory burden can be overcome by rewriting stored quantum information from one se ...

American Physical Society2020

DeepSphere: Efficient spherical convolutional neural network with HEALPix sampling for cosmological applications

Nathanaël Perraudin, Michaël Defferrard

Convolutional Neural Networks (CNNs) are a cornerstone of the Deep Learning toolbox and have led to many breakthroughs in Artificial Intelligence. So far, these neural networks (NNs) have mostly been developed for regular Euclidean domains such as those su ...

ELSEVIER SCIENCE BV2019

H0LiCOW-IX. Cosmographic analysis of the doubly imaged quasar SDSS 1206+4332 and a new measurement of the Hubble constant

Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Riccardo Agnello, Vivien François Bonvin

We present a blind time-delay strong lensing (TDSL) cosmographic analysis of the doubly imaged quasar SDSS 1206+4332. We combine the relative time delay between the quasar images, Hubble Space Telescope imaging, the Keck stellar velocity dispersion of the ...

OXFORD UNIV PRESS2019

Observable tests of self-interacting dark matter in galaxy clusters: BCG wobbles in a constant density core

David Richard Harvey

Models of cold dark matter (CDM) predict that the distribution of dark matter in galaxy clusters should be cuspy, centrally concentrated. Constant density cores would be strong evidence for beyond CDM physics, such as self-interacting dark matter (SIDM). A ...

OXFORD UNIV PRESS2019

Testing gravity with galaxy-galaxy lensing and redshift-space distortions using CFHT-Stripe 82, CFHTLenS, and BOSS CMASS datasets

Jean-Paul Richard Kneib, Huanyuan Shan

The combination of galaxy-galaxy lensing (GGL) and redshift space distortion of galaxy clustering (RSD) is a privileged technique to test general relativity predictions and break degeneracies between the growth rate of structure parameter f and the amplitu ...

EDP Sciences2019