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Related papers: Cosmology with Cosmic Voids

200 papers

A nontrivial topology of the spatial section of the universe is an observable, which can be probed for all locally homogeneous and isotropic universes, without any assumption on the cosmological density parameters. We discuss how one can…

Astrophysics · Physics 2008-11-26 M. J. Reboucas

I briefly outline a new physical interpretation to the average cosmological parameters for an inhomogeneous universe with backreaction. The variance in local geometry and gravitational energy between ideal isotropic observers in bound…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-31 David L. Wiltshire

A mildly inhomogeneous universe with a cosmological constant may look like it contains evolving dark energy. We show that could be the case by modelling the inhomogeneities and their effects in three different ways: as clumped matter…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-29 Yonadav Barry Ginat , Pedro G. Ferreira

Cosmic voids, the largest under-dense structures in the Universe, are crucial for exploring galaxy evolution. These vast, sparsely populated regions are home to void galaxies -- predominantly gas-rich, star-forming, and blue -- that evolve…

Astrophysics of Galaxies · Physics 2025-01-29 Mohammad Reza Shojaei , Saeed Tavasoli , Parsa Ghafour

We utilize the Magneticum suite of hydrodynamical simulations to investigate the formation and evolution of cosmic voids from $z = 5.04$ to present day, using cold dark matter and (sub-) halo tracers in high-density samples. This includes…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-10 Nico Schuster , Nico Hamaus , Alice Pisani , Klaus Dolag , Jochen Weller

Observations suggest that nearly seventy per cent of the energy density in the universe is unclustered and exerts negative pressure. Theoretical understanding of this component (`dark energy'), which is driving an accelerated expansion of…

Astrophysics · Physics 2007-05-23 T. Padmanabhan

Quantum cosmology describes universe as a relativistic object with an evolution defined by an equation for the energy density corresponding to the least action principle: (Taganov, 2008). In quantum cosmology this equation plays the same…

General Physics · Physics 2008-11-26 Igor N. Taganov

We propose a novel technique to probe the expansion history of the Universe based on the clustering statistics of cosmic voids. In particular, we compute their two-point statistics in redshift space on the basis of realistic mock galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-11 Nico Hamaus , P. M. Sutter , Guilhem Lavaux , Benjamin D. Wandelt

The formation of the cosmic structures in the late Universe is considered using Vlasov kinetic approach. The crucial point is the use of the gravitational potential with repulsive term of the cosmological constant which provides a solution…

General Relativity and Quantum Cosmology · Physics 2025-02-26 V. G. Gurzadyan , N. N. Fimin , V. M. Chechetkin

This is a review of the physics and cosmology of the cosmological constant. Focusing on recent developments, I present a pedagogical overview of cosmology in the presence of a cosmological constant, observational constraints on its…

Astrophysics · Physics 2015-06-24 Sean M. Carroll

Cosmic voids, the largest underdense regions in the Universe, provide unique laboratories for studying galaxy formation and constitute powerful probes of cosmology. Recent work has shown that individual galaxy bias (b_i), which quantifies…

Most of the visible matter in the Universe is in a plasma state, or more specifically is composed of ionized or partially ionized gas permeated by magnetic fields. Thanks to recent advances on the theory and detection of cosmic magnetic…

Astrophysics · Physics 2009-11-11 E. M. de Gouveia Dal Pino

The aim of this study is to distinguish genuine cosmic voids, found in a galaxy catalog by the void finder ZOBOV-VIDE, from under-dense regions in a Poisson distribution of objects. For this purpose, we perform two multivariate analyses…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-14 M. -C Cousinou , A. Pisani , A. Tilquin , N. Hamaus , A. -J Hawken , S. Escoffier

We study the dynamical properties of a large body of varying vacuum cosmologies for which dark matter interacts with vacuum. In particular, performing the critical point analysis we investigate the existence and the stability of…

General Relativity and Quantum Cosmology · Physics 2020-02-19 G. Papagiannopoulos , Pavlina Tsiapi , Spyros Basilakos , Andronikos Paliathanasis

Observational cosmology is in its "golden age" with a vast amount of recent data on the distribution of matter and light in the universe. This data can be used to probe theories of the very early universe. It is small amplitude cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Robert H. Brandenberger

A simple description of the vacuum energy (cosmological constant) problem for non-experts is presented. Basic features of cosmology with non-zero vacuum energy are discussed. The astronomical data which indicate that the universe is filled…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. D. Dolgov

We review recent advancements in cosmology with galaxy clusters. Galaxy clusters are the most massive objects in the Universe. Consequently the cluster number density as a function of cluster mass, or cluster abundance, is sensitive to…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-13 Hironao Miyatake

In this work, we present a study of the void lensing signal or the excess surface mass density (ESMD) around cosmic voids. First, we propose a new void-finder algorithm that is designed to capture the ESMD around voids. We compare our…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-27 Renan Boschetti , Pauline Vielzeuf , Marie-Claude Cousinou , Stephanie Escoffier , Eric Jullo

Cosmography, as an integral branch of cosmology, strives to characterize the Universe without relying on pre-determined cosmological models. This model-independent approach utilizes Taylor series expansions around the current epoch,…

General Physics · Physics 2024-06-11 Seokcheon Lee

This is a short overview of spatially flat (or open) four-dimensional accelerating cosmologies for some simple exponential potentials obtained by string or M theory compactification on some non-trivial curved spaces, which may lead to some…

High Energy Physics - Theory · Physics 2009-11-10 Ishwaree P. Neupane