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Related papers: An Isocurvature Mechanism for Structure Formation

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The inclusion of dissipative effects in cosmic fluids modifies their clustering properties and could have observable effects on the formation of large scale structures. We analyse the evolution of density perturbations of cold dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-14 Giovanni Acquaviva , Anslyn John , Aurélie Pénin

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 disclose the effects of an extra longitudinal degree of freedom on the evolution of perturbations in the framework of mimetic gravity. We consider a flat Friedmann-Robertson-Walker (FRW) background and explore the linear perturbations by…

General Relativity and Quantum Cosmology · Physics 2022-08-02 Bita Farsi , Ahmad Sheykhi

Theory and observations reveal fatal flaws in the standard LambdaCDM model. The cold dark matter hierarchical clustering paradigm predicts a gradual bottom-up growth of gravitational structures assuming linear, collisionless, ideal flows…

Astrophysics · Physics 2009-09-16 C. H. Gibson , T. M. Nieuwenhuizen , R. E. Schild

Cosmologies including continuous matter creation are able to reproduce the main properties of the standard $\Lambda$CDM model, in particular in cases where the particle and entropy production rates are equal. These specific models,…

General Relativity and Quantum Cosmology · Physics 2011-03-07 Alain de Roany , J. A. de Freitas Pacheco

In the last time the cold dark matter (CDM) model has suggested more and more that it is not able to describe all the properties of nearby galaxies that can be observed in great detail as well as that it has some problems in the mechanism…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Juan Magaña , Tonatiuh Matos , Victor Robles , Abril Suárez

We present the Discrete Dark Matter mechanism (DDM) which consist on the stability of the dark matter from a spontaneous breaking of a flavor symmetry group into one of its subgroups. Here we present the inclusion of the quarks on this…

High Energy Physics - Phenomenology · Physics 2012-10-26 E. Peinado

In a recent paper (arXiv:1106.4546), we introduced "dynamical dark matter," a new framework for dark-matter physics, and outlined its underlying theoretical principles and phenomenological possibilities. Unlike most traditional approaches…

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

The currently standard theory of cosmic structure formation posits that the present-day clumpy appearance of the universe developed through gravitational amplification of the matter density fluctuations that are generated in the very early…

Astrophysics · Physics 2008-11-26 Naoki Yoshida

We study the evolution of the cosmological perturbations after inflation in curvaton models where the non-relativistic curvaton decays into both radiation and a cold dark matter component. We calculate the primordial curvature and…

Astrophysics · Physics 2009-11-10 Sujata Gupta , Karim A. Malik , David Wands

Decaying dark matter (DDM) affects the evolution of cosmic structure relative to standard cold, collisionless, stable dark matter (CDM). We introduce a new semianalytic model for the effects of two-body DDM on halo structure and subhalo…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-16 Ethan O. Nadler , Andrew J. Benson

Modified dark matter (MDM, formerly known as MoNDian dark matter) is a phenomenological model of dark matter, inspired by quantum gravity. We review the construction of MDM by generalizing entropic gravity to de-Sitter space as is…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-02 Y. Jack Ng , Doug Edmonds , Duncan Farrah , Djordje Minic , Tatsu Takeuchi , Chiu Man Ho

Primordial fluctuations in the relative number densities of particles, or isocurvature perturbations, are generally well constrained by cosmic microwave background (CMB) data. A less probed mode is the compensated isocurvature perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-30 Chen He , Daniel Grin , Wayne Hu

In two-component self-interacting dark matter (SIDM) models with inter-species interactions, mass segregation arises naturally from collisional relaxation, enhancing central densities and gravothermal evolution. We demonstrate that models…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-08 Daneng Yang , Yi-Zhong Fan , Siyuan Hou , Yue-Lin Sming Tsai

In this paper we explore the effect of decaying dark matter (DDM) on large-scale structure and possible constraints from galaxy imaging surveys. DDM models have been studied, in part, as a way to address apparent discrepancies between the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Mei-Yu Wang , Andrew R. Zentner

Warm dark matter (WDM) is an intriguing model of structure formation from the point of view of both cosmology and particle physics. We consider a one-parameter family of WDM models. The linear power spectra for these models is calculated…

Astrophysics · Physics 2010-11-30 Stephane Colombi , Scott Dodelson , Lawrence M. Widrow

A new phenomenological dark energy model, originally associated to the large-scale structure formation and considered as a solution to the fine-tuning and coincidence problems related to the cosmological constant, was analyzed within the…

General Relativity and Quantum Cosmology · Physics 2026-03-05 A. Kazım Çamlıbel

If dark energy interacts with dark matter, there is a change in the background evolution of the universe, since the dark matter density no longer evolves as a^{-3}. In addition, the non-gravitational interaction affects the growth of…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-24 Gabriela Caldera-Cabral , Roy Maartens , Bjoern Malte Schaefer

I review recent results derived from numerical simulations of the turbulent interstellar medium (ISM), in particular concerning the nature and formation of turbulent clouds, methods for comparing the structure in simulations and…

Astrophysics · Physics 2018-03-28 Enrique Vázquez-Semadeni

The collisionless cold dark matter (CCDM) model predicts overly dense cores in dark matter halos and overly abundant subhalos. We show that the idea that CDM are decaying superheavy particles which produce ultra-high energy cosmic rays with…

Astrophysics · Physics 2009-11-10 Chung-Hsien Chou , Kin-Wang Ng
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