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Related papers: An Isocurvature Mechanism for Structure Formation

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Inelastic dark matter (IDM) models feature an energy threshold for scattering with Standard Model particles, which enables their consistency with the increasingly stringent limits placed by direct detection experiments. In a typical…

High Energy Physics - Phenomenology · Physics 2025-10-15 Zamiul Alam , Christopher V. Cappiello , Francesc Ferrer

Analytic formulas reproducing the warm dark matter (WDM) primordial spectra are obtained for WDM particles decoupling in and out of thermal equilibrium which provide the initial data for WDM non-linear structure formation. We compute and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 C. Destri , H. J. de Vega , N. G. Sanchez

In a universe with quintessence isocurvature, or perturbations in dark energy that are independent from the usual curvature perturbations, structure formation is changed qualitatively. The existence of two independent fields, curvature and…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-23 Drew Jamieson , Marilena LoVerde

Dark-matter halos are the scaffolding around which galaxies and clusters are built. They form when the gravitational instability of primordial density fluctuations causes regions which are denser than average to slow their cosmic expansion,…

Astrophysics · Physics 2007-05-23 Paul R. Shapiro , Ilian T. Iliev , Hugo Martel , Kyungjin Ahn , Marcelo A. Alvarez

In inhomogeneous cosmology, restricting attention to an irrotational dust matter model, backreaction arises in terms of the deviation of the averaged spatial scalar curvature from a constant-curvature model on some averaging domain $D$,…

General Relativity and Quantum Cosmology · Physics 2019-08-12 Quentin Vigneron , Thomas Buchert

The canonical cosmological constant dominated cold dark matter model (LCDM) may possess too much power on small scales at z=0, manifested as central over-concentration of dark matter and over-abundance of dwarf galaxies. We suggest an…

Astrophysics · Physics 2009-10-31 Renyue Cen

Despite overwhelming observational evidence for dark matter, we still have no evidence of direct detection. Consequently, our knowledge about dark matter is limited, for example, we do not know if dark matter is a stable particle or if it…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-30 Earl Lester , Krzysztof Bolejko

Decaying dark matter models provide a physically motivated way of channeling energy between the matter and radiation sectors. In principle, this could affect the predicted value of the Hubble constant in such a way as to accommodate the…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-04 Emil Brinch Holm , Thomas Tram , Steen Hannestad

We present results from a set of high (512^3 effective resolution), and ultra-high (1024^3) SPH adiabatic cosmological simulations of cluster formation aimed at studying the internal structure of the intracluster medium (ICM). We derive a…

Astrophysics · Physics 2009-11-10 G. Yepes , Y. Ascasibar , R. Sevilla , S. Gottlober , V. Muller

We use numerical relativity simulations to describe the spacetime evolution during nonlinear structure formation in $\Lambda$CDM cosmology. Fully nonlinear initial conditions are set at an initial redshift $z\approx 300$, based directly on…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-12 Robyn L. Munoz , Marco Bruni

Self-Destructing Dark Matter (SDDM) is a class of dark sector models in which the collision of a dark sector particle with the earth induces its prompt decay into Standard Model particles, generating unique signals at neutrino detectors.…

High Energy Physics - Phenomenology · Physics 2021-08-18 Michael Geller , Ofri Telem

Using a model for an ideal fluid with a variable number of particles, a phenomenological description of the processes of particle production in strong external fields is investigated. The conformal invariance of the creation law is shown,…

General Relativity and Quantum Cosmology · Physics 2023-12-13 Victor Berezin , Inna Ivanova

General relativity can be reconciled with quantum field theory without quantising the geometry only if the metric evolves stochastically. In this article, we explore the consequences of such a proposal at early cosmological times. We find…

General Relativity and Quantum Cosmology · Physics 2026-05-29 Jonathan Oppenheim , Emanuele Panella , Andrew Pontzen

The Standard Cosmological Model assumes that more than 85\% of matter is in the form of collisionless and pressureless dark matter. Unstable decaying dark matter has been proposed in the literature as an extension to the standard cold dark…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-17 Earl Lester , Krzysztof Bolejko

This paper examines the growth of dark matter and dark energy perturbations within a non-canonical scalar field model characterized by an exponential potential. Through dynamical system analysis, we identify critical points and track the…

General Relativity and Quantum Cosmology · Physics 2025-10-21 Zanyar Ebrahimi , Kayoomars Karami

Based on the proposed unifying theory of dark matter and quintessence, a novel nonlinear structure formation scenario is suggested. This top-down singular and turbulent scenario results in a bottom-up hierarchical clustering and is…

General Physics · Physics 2007-05-23 Reza Dastvan

We revisit a cosmological model where dark matter (DM) and dark energy (DE) follow barotropic equations of state, allowing deviations from the standard $\Lambda$CDM framework (i.e. $w_{dm} \neq 0$, $w_{de} \neq -1$), considering both flat…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-24 Dorian Araya , Cristian Castillo , Genly Leon , Juan Magaña , Angie Barr Domínguez , Miguel A. García-Aspeitia

We study particle decay as the origin of dark radiation. After elaborating general properties and useful parametrisations we provide model-independent and easy-to-use constraints from nucleosynthesis, the cosmic microwave background and…

High Energy Physics - Phenomenology · Physics 2014-02-14 Jasper Hasenkamp , Jörn Kersten

Within the framework of DBI non-canonical scalar field model of dark energy, we study the growth of dark matter perturbations in the both linear and non-linear regimes. In our DBI model, we consider the anti-de Sitter warp factor…

General Relativity and Quantum Cosmology · Physics 2018-10-30 K. Fahimi , K. Karami , S. Asadzadeh , K. Rezazadeh

Dynamical dark matter (DDM) is a new framework for dark-matter physics in which the dark sector comprises an ensemble of individual component fields which collectively conspire to act in ways that transcend those normally associated with…

High Energy Physics - Phenomenology · Physics 2013-05-30 Keith R. Dienes , Shufang Su , Brooks Thomas