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Related papers: Number Counts and Dynamical Vacuum Cosmologies

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We suggest an alternative framework for interpreting the current state of the visible universe. Our approach is based on a dynamical ``Cosmological Constant'' and the starting point is that a decaying vacuum produces matter. As we point…

Astrophysics · Physics 2014-10-13 Manasse R. Mbonye

We present an extensive comparison of models of structure formation with observations, based on linear and quasi-linear theory. We assume a critical matter density, and study both cold dark matter models and cold plus hot dark matter…

Astrophysics · Physics 2015-06-24 Andrew R Liddle , David H Lyth , R K Schaefer , Q Shafi , Pedro T P Viana

We show that decoupled hidden sectors can have observational consequences. As a representative model example, we study dark matter production in the Higgs portal model with one real singlet scalar $s$ coupled to the Standard Model Higgs via…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-16 Matti Heikinheimo , Tommi Tenkanen , Kimmo Tuominen , Ville Vaskonen

We consider a self-interacting dark matter model in which the massive dark photon mediating the self-interaction decays to light dark fermions to avoid over-closing the universe. We find that if the model is constrained to explain the dark…

High Energy Physics - Phenomenology · Physics 2019-07-05 Ran Huo , Manoj Kaplinghat , Zhen Pan , Hai-Bo Yu

The mass function of dark halos in a Lambda-dominated cold dark matter (LambdaCDM) universe is investigated. 529 output files from five runs of N-body simulations are analyzed using the friends-of-friends cluster finding algorithm. All the…

Astrophysics · Physics 2009-11-10 Hideki Yahagi , Masahiro Nagashima , Yuzuru Yoshii

[Abridged] We use data on massive galaxy clusters ($M_{\rm cluster} > 8 \times 10^{14} h^{-1} M_\odot$ within a comoving radius of $R_{\rm cluster} = 1.5 h^{-1}\Mpc$) in the redshift range $0.05 \lesssim z \lesssim 0.83$ to place…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 L. Campanelli , G. L. Fogli , T. Kahniashvili , A. Marrone , Bharat Ratra

We investigate models of interacting dark matter and dark energy for the universe in a spatially flat Friedmann-Robertson-Walker (FRW) space-time. We find the "source equation" for the total energy density and determine the energy density…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Luis P. Chimento

The observational data on the large scale structure (LSS) of the Universe are used to determine cosmological parameters within the class of adiabatic inflationary models. We show that a mixed dark matter model with cosmological constant…

Astrophysics · Physics 2007-05-23 B. Novosyadlyj , R. Durrer , S. Apunevych

We consider a cosmological model with an interaction between dark matter and dark energy which leaves the background cosmology unaffected and only affects the evolution of the perturbations. This is achieved by introducing a coupling given…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-21 Mahnaz Asghari , Jose Beltran Jimenez , Shahram Khosravi , David F. Mota

We investigate how inhomogeneous quintessence models may have a specific signature even in the linear regime of large scale structure formation. The dynamics of the collapse of a dark matter halo is governed by the value or the dynamical…

Astrophysics · Physics 2008-11-26 N. J. Nunes , D. F. Mota

So far, there have been no theories or observational data that deny the presence of interaction between dark energy and dark matter. We extend naturally the holographic dark energy (HDE) model, proposed by Granda and Oliveros, in which the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Fei Yu , Jingfei Zhang , Jianbo Lu , Wei Wang , Yuanxing Gui

In $\Lambda$CDM cosmology, structure formation is halted shortly after dark energy dominates the mass/energy budget of the Universe. A manifestation of this effect is that in such a cosmology the turnaround radius has an upper bound.…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Dimitrios Tanoglidis , Vasiliki Pavlidou , Theodore Tomaras

We derive and analyze a class of spherically symmetric cosmological models whose source is an interactive mixture of inhomogeneous cold dark matter (DM) and a generic homogeneous dark energy (DE) fluid. If the DE fluid corresponds to a…

Astrophysics · Physics 2009-11-10 Roberto A Sussman , Israel Quiros , Osmel Martin Gonzalez

The cosmological model of dark energy interacting with cold dark matter without coupling to the baryonic matter, is studied in the background of both classical Einstein and loop quantum cosmology. We consider two types of interacting…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Song Li , Yongge Ma

We perform a study both statistical and theoretical for cosmological models of matter creation and their ability to describe effective phantom models of dark energy. Such models are beyond the $\Lambda$CDM model since the resulting cosmic…

General Relativity and Quantum Cosmology · Physics 2020-04-23 Víctor H. Cárdenas , Miguel Cruz , Samuel Lepe , Shin'ichi Nojiri , Sergei D. Odintsov

In this paper, we introduce a novel class of interacting vacuum models, based on recasting the equation of state originally developed in the context of lattice kinetic theory by Shan \& Chen as the coupling between the vacuum and cold dark…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-01 Natalie B. Hogg , Marco Bruni

In this work we study the evolution of matter-density perturbations for an arbitrary $\Lambda(t)$ model, and specialize our analysis to the particular phenomenological law $\Lambda = \Lambda_0 + 3\beta H^2$. We study the evolution of the…

General Relativity and Quantum Cosmology · Physics 2013-11-01 Dennis Bessada , Oswaldo D. Miranda

In this review we consider in detail different theoretical topics associated with interaction in the dark sector. We study linear and nonlinear interactions which depend on the dark matter and dark energy densities. We consider a number of…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-25 Yu. L. Bolotin , A. Kostenko , O. A. Lemets , D. A. Yerokhin

Quasi--local scalar variables approach is applied to a spherically symmetric inhomogeneous Lema\^\i tre--Tolman--Bondi metric containing a mixture of non-relativistic cold dark matter and coupled dark energy with constant equation of state.…

General Relativity and Quantum Cosmology · Physics 2017-11-15 German Izquierdo , Roberto C. Blanquet-Jaramillo , Roberto A. Sussman

Models with non-gravitational interactions between the dark matter and dark energy components are an alternative to the standard cosmological scenario. These models are characterized by an interaction term, and a frequently used…

General Relativity and Quantum Cosmology · Physics 2020-12-07 R. von Marttens , H. A. Borges , S. Carneiro , J. S. Alcaniz , W. Zimdahl