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Models proposing a non-gravitational interaction between dark energy (DE) and dark matter (CDM) have been extensively studied as alternatives to the standard cosmological model. A common approach to describing the DE-CDM coupling assumes it…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-22 Jaelsson S. Lima , Rodrigo von Marttens , Luciano Casarini

We lay out the framework to numerically study nonlinear structure formation in the context of scalar-field-coupled cold dark matter models (phiCDM models) where the scalar field phi serves as dynamical dark energy. Adopting parameters for…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 HongSheng Zhao , Andrea V. Maccio' , Baojiu Li , Henk Hoekstra , Martin Feix

We reconsider the dynamics of the Universe in the presence of interactions in the cosmological dark sector. A class of interacting models is introduced via a real function $f\left(r\right)$ of the ratio $r$ between the energy densities of…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-09 R. von Marttens , L. Casarini , D. F. Mota , W. Zimdahl

We study cosmological perturbations in the context of an interacting dark energy model, in which the cosmological term decays linearly with the Hubble parameter, with concomitant matter production. A previous joint analysis of the…

Astrophysics · Physics 2008-11-26 H. A. Borges , S. Carneiro , J. C. Fabris , C. Pigozzo

Interacting dark sectors may undergo changes in the number of their relativistic species during the early universe, due to a mass threshold $m$ (similar to changes in the Standard Model bath), and in doing so affect the cosmic history. When…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-22 Itamar J. Allali , Fabrizio Rompineve , Mark P. Hertzberg

Based on flat Friedmann-Robertson Walker cold dark matter (CDM) type models driven by non-relativistic matter and an exotic fluid (quintessence) with an equation of state: $p_{Q}=w\rho_{Q}$ ($-1\le w<0$), we investigate whether or not the…

Astrophysics · Physics 2009-11-07 S. Basilakos

We investigate the observational viability of a class of interacting dark energy (iDE) models in the light of the latest Cosmic Microwave Background (CMB), type Ia supernovae (SNe) and SH0ES Hubble parameter measurements. Our analysis…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-10 Micol Benetti , Humberto Borges , Cassio Pigozzo , Saulo Carneiro , Jailson Alcaniz

Some physical imprints of quintessence scalar fields on dark matter (DM) clustering are illustrated, and a comparison with the concordance model $\Lambda CDM$ is highlighted. First, we estimate the cosmological parameters for two…

Astrophysics · Physics 2009-03-04 A. Fuzfa J. -M. Alimi

The recent observational evidence for the current cosmic acceleration have stimulated renewed interest in alternative cosmologies, such as scenarios with interaction in the dark sector (dark matter and dark energy). In general, such models…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-22 R. S. Goncalves , J. S. Alcaniz , A. Dev , D. Jain

We investigated a possible interaction between cold dark matter and dark energy, corresponding to a well-known interacting dark energy model discussed in the literature within the context of resolving the Hubble tension. We put constraints…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-21 David Benisty , Supriya Pan , Denitsa Staicova , Eleonora Di Valentino , Rafael C. Nunes

Sheth-Tormen mass function has been widely used to quantify the abundance of dark matter halos. It is a significant improvement over the Press-Schechter mass function as it uses ellipsoidal collapse in place of spherical collapse. Both of…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Swati Gavas , J S Bagla , Nishikanta Khandai , Girish Kulkarni

In this work we present the cosmological dynamics of interacting dark energy models in the framework of particle creation mechanism. The particle creation mechanism presented here describes the true non equilibrium thermodynamics of the…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Sujay Kr. Biswas , Wompherdeiki Khyllep , Jibitesh Dutta , Subenoy Chakraborty

Accounting for large-scale structure in our universe will require not only reasonably accurate mathematical models of its cosmogony, topology and cosmology, but also a more deeper understanding of our fundamental physical concepts of space,…

Astrophysics · Physics 2016-08-30 Charles B. Leffert

We argue that a few per cent of "Early Dark Energy" can be detected by the statistics of nonlinear structures. The presence of Dark Energy during linear structure formation is natural in models where the present tiny Dark-Energy density is…

Astrophysics · Physics 2009-01-28 Matthias Bartelmann , Michael Doran , Christof Wetterich

We extend the cosmological couplings proposed in Sun et al. and Wei, where they suggested interactions with change of signs along the cosmological evolution. Our extension liberates the changes of sign of the interaction from the…

General Relativity and Quantum Cosmology · Physics 2014-09-25 Mónica Forte

We use the presently observed number density of large X-ray clusters and linear mass power spectra to constrain the shape parameter ($\Gamma$), the spectral index ($n$), the amplitude of matter density perturbations on the scale of $8…

Astrophysics · Physics 2010-12-13 Jiun-Huei Proty Wu

The present work deals with a kinematic approach to the modelling the late time dynamics of the universe. This approach is based upon the assumption of constant value of cosmological jerk parameter, which is the dimensionless representation…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-12 Ankan Mukherjee , Narayan Banerjee

We investigate the observational constraints on an interacting vacuum energy scenario with two different neutrino schemes (with and without a sterile neutrino) using the most recent data from CMB temperature and polarization anisotropy,…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-15 Suresh Kumar , Rafael C. Nunes

We investigate a cosmological scenario in which the dark matter particles can be created during the evolution of the Universe. By regarding the Universe as an open thermodynamic system and using non-equilibrium thermodynamics, we examine…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-20 Z. Safari , K. Rezazadeh , B. Malekolkalami

We discuss an interacting dark sector model featuring decaying vacuum energy and dark matter empowered by gravitationally induced matter creation. Motivated by quantum field theoretic considerations of vacuum decay and adiabatic particle…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-17 Lokesh Chander , C P Singh