Publications associées à Futur d'un univers en expansion

Tracing the rise of supermassive black holes A panchromatic search for faint, unobscured quasars at z ≥ 6 with COSMOS-Web and other surveys

We report the identification of 64 new candidates of compact galaxies, potentially hosting faint quasars with bolometric luminosities of L-bol = 10(43)-10(46) erg s(-1), residing in the reionization epoch within the redshift range of 6 less than or similar ...

Edp Sciences S A2024

A generalization of the Hawking black hole area theorem

Veronica Sacchi

Hawking's black hole area theorem was proven using the null energy condition (NEC), a pointwise condition violated by quantum fields. The violation of the NEC is usually cited as the reason that black hole evaporation is allowed in the context of semiclass ...

Springer/Plenum Publishers2024

CLASSY. VIII. Exploring the Source of Ionization with UV Interstellar Medium Diagnostics in Local High-z Analogs

Adèle Marie Françoise Plat, Xinfeng Xu

In the current JWST era, rest-frame UV spectra play a crucial role in enhancing our understanding of the interstellar medium (ISM) and stellar properties of the first galaxies in the epoch of reionization (z > 6). Here, we compare well-known and reliable o ...

Iop Publishing Ltd2024

Dilute neutron star matter from neural-network quantum states

Giuseppe Carleo

Low-density neutron matter is characterized by fascinating emergent quantum phenomena, such as the formation of Cooper pairs and the onset of superfluidity. We model this density regime by capitalizing on the expressivity of the hidden-nucleon neural-netwo ...

AMER PHYSICAL SOC2023

CosmoLattice: A modern code for lattice simulations of scalar and gauge field dynamics in an expanding universe

Daniel Garcia Figueroa, Adrien Florio, Wessel Valkenburg, Francisco Torrenti

This paper describes CosmoGattice, a modern package for lattice simulations of the dynamics of interacting scalar and gauge fields in an expanding universe. CosmoGattice incorporates a series of features that makes it very versatile and powerful: i) it is ...

ELSEVIER2023

GOGREEN: A critical assessment of environmental trends in cosmological hydrodynamical simulations at z approximate to 1

Pascale Jablonka, Hung-Hsu Chan

Recent observations have shown that the environmental quenching of galaxies at z & SIM; 1 is qualitatively different to that in the local Universe. However, the physical origin of these differences has not yet been elucidated. In addition, while low-redshi ...

OXFORD UNIV PRESS2023

Near-infrared emission line diagnostics for AGN from the local Universe to z ∼ 3

Michaela Hirschmann

Optical rest-frame spectroscopic diagnostics are usually employed to distinguish between star formation and active galactic nucleus (AGN) powered emission. However, this method is biased against dusty sources, hampering a complete census of the AGN populat ...

Edp Sciences S A2023

Strong gravitational lensing by AGNs as a probe of the quasar-host relations in the distant Universe

Frédéric Courbin, Malte Tewes, Martin Raoul Robert Millon, Aymeric Alexandre Galan

A rare case of a quasar acting as a gravitational lens allows a precise determination of the mass of the quasar's host galaxy and offers a new path to studying the connections between supermassive black holes and their host galaxies. ...

NATURE PORTFOLIO2023

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

The imprint of galaxy mergers on satellite planes in a cosmological context

Oliver Müller

Flattened and kinematically correlated planes of dwarf satellite galaxies have been observed in the Local Volume. The slinging out of satellites during host galaxy mergers has been suggested as a formation mechanism for these peculiar structures. We statis ...

2023

H I constraints from the cross-correlation of eBOSS galaxies and Green Bank Telescope intensity maps

Jean-Paul Richard Kneib

We present the joint analysis of Neutral Hydrogen (H I) Intensity Mapping observations with three galaxy samples: the Luminous Red Galaxy (LRG) and Emission Line Galaxy (ELG) samples from the eBOSS survey, and the WiggleZ Dark Energy Survey sample. The H I ...

OXFORD UNIV PRESS2022

Freeze-in and freeze-out generation of lepton asymmetries after baryogenesis in the nu MSM

Mikhail Chapochnikov, Shintaro Eijima, Inar Timiryasov

The nu MSM an extension of the Standard Model by three relatively light singlet Majorana fermions N-1,N-2,N-3 allows for the generation of lepton asymmetry which is several orders of magnitude larger than the observed baryon asymmetry of the Universe. The ...

IOP Publishing Ltd2022

Virgo Filaments. II. Catalog and First Results on the Effect of Filaments on Galaxy Properties

Pascale Jablonka, Gianluca Castignani

Virgo is the nearest galaxy cluster; it is thus ideal for studies of galaxy evolution in dense environments in the local universe. It is embedded in a complex filamentary network of galaxies and groups, which represents the skeleton of the large-scale Lani ...

IOP Publishing Ltd2022

Learning convergence prediction of astrobots in multi-object spectrographs

Denis Gillet, Jean-Paul Richard Kneib, Matin Macktoobian, Francesco Basciani

Astrobot swarms are used to capture astronomical signals to generate the map of the observable universe for the purpose of dark energy studies. The convergence of each swarm in the course of its coordination has to surpass a particular threshold to yield a ...

2021

The art of simulating the early universe. Part I. Integration techniques and canonical cases

Daniel Garcia Figueroa, Adrien Florio, Wessel Valkenburg, Francisco Torrenti

We present a comprehensive discussion on lattice techniques for the simulation of scalar and gauge field dynamics in an expanding universe. After reviewing the continuum formulation of scalar and gauge field interactions in Minkowski and FLRW backgrounds, ...

2021

Data-Driven Convergence Prediction of Astrobots Swarms

Denis Gillet, Jean-Paul Richard Kneib, Matin Macktoobian, Francesco Basciani

Astrobots are robotic artifacts whose swarms are used in astrophysical studies to generate the map of the observable universe. These swarms have to be coordinated with respect to various desired observations. Such coordination\footnote{\z{A coordination sa ...

2022

Optimal target assignment for massive spectroscopic surveys

Denis Gillet, Jean-Paul Richard Kneib, Matin Macktoobian

Robotics have recently contributed to cosmological spectroscopy to automatically obtain the map of the observable universe using robotic fiber positioners. For this purpose, an assignment algorithm is required to assign each robotic fiber positioner to a t ...

2020

Schwinger production of scalar particles during and after inflation from the first principles

Oleksandr Sobol

By using the first-principles approach, we derive a system of three quantum kinetic equations governing the production and evolution of charged scalar particles by an electric field in an expanding universe. Analyzing the ultraviolet asymptotic behavior of ...

American Physical Society2020

Aspects of Gauge Theories Vacua

Adrien Florio

This thesis is concerned with gauge theories, their complicated vacuum and resulting effects. After an introduction to the subject, it is divided into four parts. Firstly, we treat the problem of chiral charge dynamics at finite temperature. Quantum field ...

EPFL2020

The Navigation of Robotic Fiber Positioners in SDSS-V Project: Design and Implementation

Denis Gillet, Jean-Paul Richard Kneib, Matin Macktoobian

SDSS-V project is one of the major observational cosmological projects which aims to generate the map of the observable universe by collecting spectroscopic data from the sky using optical fibers. Each optical fiber is attached to a robotic positioner to b ...

IEEE2019