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Strongly Coupled Dark Energy plus Warm dark matter (SCDEW) cosmologies admit the stationary presence of $\sim 1\, \%$ of coupled-DM and DE, since inflationary reheating. Coupled-DM fluctuations therefore grow up to non-linearity even in the…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-12 Silvio A. Bonometto , Roberto Mainini

Cosmologies including strongly Coupled (SC) Dark Energy (DE) and Warm dark matter (SCDEW) are based on a conformally invariant (CI) attractor solution modifying the early radiative expansion. Then, aside of radiation, a kinetic field $\Phi$…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-18 Silvio A. Bonometto , Marino Mezzetti , Roberto Mainini

In this second paper we present the first Nbody cosmological simulations of strongly coupled Dark Energy models (SCDEW), a class of models that alleviates theoretical issues related to the nature of dark energy. SCDEW models assume a strong…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-09 Andrea V. Macciò , Roberto Mainini , Camilla Penzo , Silvio A. Bonometto

In the early Universe, a dual component made of coupled CDM and a scalar field $\Phi$, if their coupling $\beta > \sqrt{3}/2$, owns an attractor solution, making them a stationary fraction of cosmic energy during the radiation dominated…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Silvio A. Bonometto , Roberto Mainini

In this first paper we discuss the linear theory and the background evolution of a new class of models we dub SCDEW: Strongly Coupled DE, plus WDM. In these models, WDM dominates today's matter density; like baryons, WDM is uncoupled. Dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-09 Silvio A. Bonometto , Roberto Mainini , Andrea V. Macciò

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

In this work we investigate the spherical collapse model in flat FRW dark energy universes. We consider the Holographic Dark Energy (HDE) model as a dynamical dark energy scenario with a slowly time-varying equation-of-state (EoS) parameter…

General Relativity and Quantum Cosmology · Physics 2015-01-27 Tayebe Naderi , Mohammad Malekjani , Francesco Pace

The growth of the density fluctuations is considered to be an important cosmological test. In the standard model, for a matter dominated universe, the growth of the density perturbations evolves with redshift z like (1/{1+z))^s with s=1.…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-17 Andre Maeder , Vesselin G. Gueorguiev

We study the evolving environment dependence of mass accretion by dark haloes in simulations of cold and warm dark matter (CDM and WDM) cosmologies. The latter allows us to probe the nature of halo growth at scales below the WDM half-mode…

Astrophysics of Galaxies · Physics 2022-03-01 Payaswinee Dhoke , Aseem Paranjape

Models including an energy transfer from CDM to DE are widely considered in the literature, namely to allow DE a significant high-z density. Strongly Coupled cosmologies assume a much larger coupling between DE and CDM, together with the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-26 S. A. Bonometto , M. Mezzetti , I. Musco , R. Mainini , A. V. Maccio'

Observations have confirmed the accelerated expansion of the universe. The accelerated expansion can be modelled by invoking a cosmological constant or a dynamical model of dark energy. A key difference between these models is that the…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Manvendra Pratap Rajvanshi , Jasjeet Singh Bagla

In the cuprate superconductors, the spatial coherence of the charge density wave (CDW) state grows rapidly below a characteristic temperature $T_\mathrm{CDW}$, the nature of which is debated. We have combined a set of x-ray scattering…

We present a framework for high-redshift ($z \geq 7$) galaxy formation that traces their dark matter (DM) and baryonic assembly in four cosmologies: Cold Dark Matter (CDM) and Warm Dark Matter (WDM) with particle masses of $m_x =$ 1.5, 3…

Astrophysics of Galaxies · Physics 2015-06-17 Pratika Dayal , Andrei Mesinger , Fabio Pacucci

It is known that the unregularized expressions for the stress-energy tensor components corresponding to subhorizon and superhorizon vacuum fluctuations of a massless scalar field in a Friedmann-Robertson-Walker background are characterized…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Ali Kaya

We study clusters in Warm Dark Matter (WDM) models of a thermally produced dark matter particle $0.5$ keV in mass. We show that, despite clusters in WDM cosmologies having similar density profiles as their Cold Dark Matter (CDM)…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Pascal J. Elahi , Hareth S. Mahdi , Chris Power , Geraint F. Lewis

In the context of a spatially flat $\Lambda(t)$CDM cosmology, we investigate interacting dark energy (IDE) scenarios characterized by phenomenological interaction terms proportional to the Hubble expansion rate and the dark energy density.…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-13 A. A. Escobal , H. A. P. Macedo , J. F. Jesus , R. C. Nunes , J. A. S. Lima

LCDM cosmological models with Early Dark Energy (EDE) have been proposed to resolve tensions between the Hubble constant H0 = 100h km/s/Mpc measured locally, giving h ~ 0.73, and H0 deduced from Planck cosmic microwave background (CMB) and…

Galactic stellar haloes are largely composed of the remnants of galaxies accreted during the assembly of their host galaxies, and hence their properties reflect the mass spectrum and post-accretion evolution of their satellites. As the…

We examine a cosmological model with a dark energy density of the form $\rho_{DE}(t)=\rho_X(t)+\rho_Z(t)$, where $\rho_X$ is the component that accelerates the Hubble expansion at late times and $\rho_Z(t)$ is an extra contribution…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-22 Michele Maggiore , Lukas Hollenstein , Maud Jaccard , Ermis Mitsou

We compute the number density of massive Black Holes (BHs) at the centre of galaxies at z=6 in different Dynamical Dark Energy (DDE) cosmologies, and compare it with existing observational lower limits, to derive constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Alessandra Lamastra , Nicola Menci , Fabrizio Fiore , Cinzia Di Porto , Luca Amendola
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