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Concept

Hubble volume

Related publications (32)

Time-Delay Cosmography: Measuring the Hubble Constant and Other Cosmological Parameters with Strong Gravitational Lensing

Frédéric Courbin, Martin Raoul Robert Millon

Multiply lensed images of a same source experience a relative time delay in the arrival of photons due to the path length difference and the different gravitational potentials the photons travel through. This effect can be used to measure absolute distance ...

Springer2024

Small-amplitude Red Giants Elucidate the Nature of the Tip of the Red Giant Branch as a Standard Candle

Richard Irving Anderson, Nolan Wayne Koblischke

The tip of the red giant branch (TRGB) is an important standard candle for determining luminosity distances. Although several 105 small-amplitude red giant stars (SARGs) have been discovered, variability was previously considered irrelevant for the TRGB as ...

Iop Publishing Ltd2024

TDCOSMO I. An exploration of systematic uncertainties in the inference ofH(0)from time-delay cosmography

Frédéric Courbin

Strong-lensing time delays enable the measurement of the Hubble constant (H0) independently of other traditional methods. The main limitation to the precision of time-delay cosmography is mass-sheet degeneracy (MSD). Some of the previous TDCOSMO analyses b ...

EDP SCIENCES S A2023

Constraints on the Hubble constant from supernova Refsdal's reappearance

Vivien François Bonvin, Martin Raoul Robert Millon

The gravitationally lensed supernova Refsdal appeared in multiple images produced through gravitational lensing by a massive foreground galaxy cluster. After the supernova appeared in 2014, lens models of the galaxy cluster predicted that an additional ima ...

American Association for the Advancement of Science2023

The Magnificent Five Images of Supernova Refsdal: Time Delay and Magnification Measurements

Vivien François Bonvin, Martin Raoul Robert Millon

In late 2014, four images of Supernova (SN) "Refsdal," the first known example of a strongly lensed SN with multiple resolved images, were detected in the MACS J1149 galaxy-cluster field. Following the images' discovery, the SN was predicted to reappear wi ...

IOP Publishing Ltd2023

Crowded No More: The Accuracy of the Hubble Constant Tested with High-resolution Observations of Cepheids by JWST

Richard Irving Anderson

High-resolution James Webb Space Telescope (JWST) observations can test confusion-limited Hubble Space Telescope (HST) observations for a photometric bias that could affect extragalactic Cepheids and the determination of the Hubble constant. We present JWS ...

Iop Publishing Ltd2023

Strong and micro lensing in distant quasars

Eric Gérard Guy Paic

Most large galaxies contain Super Massive Black Holes at their centers, drawing matter nearby to form swirling accretion disks emitting electromagnetic radiation. These are Active Galactic Nuclei. The brightest quasars are the most luminous Universe object ...

EPFL2023

Beyond - ?CDM constraints from the full shape clustering measurements from BOSS and eBOSS

Cheng Zhao

We analyse the full shape of anisotropic clustering measurements from the extended Baryon Oscillation Spectroscopic Survey quasar sample together with the combined galaxy sample from the Baryon Oscillation Spectroscopic Survey. We obtain constraints on the ...

OXFORD UNIV PRESS2023

Cosmological implications of the full shape of anisotropic clustering measurements in BOSS and eBOSS

Cheng Zhao

We present the analysis of the full shape of anisotropic clustering measurement from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) quasar sample together with the combined galaxy sample from the Baryon Oscillation Spectroscopic Survey (BOSS) ...

OXFORD UNIV PRESS2022

Cosmology with Large Scale Structures using Massive Spectroscopic Surveys

Amélie Tamone

Spectroscopic surveys aim to map large fractions of the Universe to study the Large Scale Structures (LSS). LSS evolution traces the distribution of matter as a result of the tension between the expansion of the Universe and the gravitational forces, which ...

EPFL2022

Next generation modeling techniques for strong gravitational lensing and measuring the Hubble constant

Aymeric Alexandre Galan

For many years, observations of the Universe suggest a series problems with our theoretical models, particularly its dark energy and dark matter components. Fortunately, the Universe also provides us with a tool to solve these problems, called strong gravi ...

EPFL2022

A machine learning approach to correct for mass resolution effects in simulated halo clustering statistics

Cheng Zhao, Daniel Felipe Forero Sanchez

The increase in the observed volume in cosmological surveys imposes various challenges on simulation preparations. First, the volume of the simulations required increases proportionally to the observations. However, large-volume simulations are quickly bec ...

OXFORD UNIV PRESS2022

Measuring accretion disk sizes of lensed quasars with microlensing time delay in multi-band light curves

Frédéric Courbin, Hung-Hsu Chan, Vivien François Bonvin, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate

Time-delay cosmography in strongly lensed quasars offers an independent way of measuring the Hubble constant, H-0. However, it has been proposed that the combination of microlensing and source-size effects, also known as microlensing time delay, can potent ...

EDP SCIENCES S A2021

Time-delay Cosmography with Strongly Lensed Quasars

Martin Raoul Robert Millon

The LCDM model has emerged as the concordance model of cosmology for its ability to explain a variety of observations, ranging from the anisotropies of the Cosmic Microwave Background (CMB) to the accelerated expansion of the Universe. However, with the ev ...

EPFL2021

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

Whole Body Model Predictive Control with a Memory of Motion: Experiments on a Torque-Controlled Talos

Sylvain Calinon, Teguh Santoso Lembono

This paper presents the first successful experiment implementing whole-body model predictive control with state feedback on a torque-control humanoid robot. We demonstrate that our control scheme is able to do whole-body target tracking, control the balanc ...

IEEE2021

TDCOSMO: I. An exploration of systematic uncertainties in the inference of H-0 from time-delay cosmography

Frédéric Courbin, Hung-Hsu Chan, Martin Raoul Robert Millon, Aymeric Alexandre Galan

Time-delay cosmography of lensed quasars has achieved 2.4% precision on the measurement of the Hubble constant, H0. As part of an ongoing effort to uncover and control systematic uncertainties, we investigate three potential sources: 1- stellar kinematics, ...

EDP SCIENCES S A2020

TDCOSMO. IV. Hierarchical time-delay cosmography - joint inference of the Hubble constant and galaxy density profiles

Frédéric Courbin, Martin Raoul Robert Millon, Aymeric Alexandre Galan

The H0LiCOWcollaboration inferred via strong gravitational lensing time delays a Hubble constant value of H0 = 73 :3+1:7 1:8 km s 1 Mpc 1, describing deflector mass density profiles by either a power-law or stars (constant mass-to-light ratio) plus standar ...

EDP SCIENCES S A2020

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

Chiral fermion asymmetry in high-energy plasma simulations

Salim Bennouna

The chiral magnetic effect (CME) is a quantum relativistic effect that describes the appearance of an additional electric current along a magnetic field. It is caused by an asymmetry between the number densities of left- and right-handed fermions, which ca ...

2020