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Related papers: Non-comoving Cold Dark Matter in a $\Lambda$CDM ba…

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Starting from an inhomogeneous space-time model of the universe we could recreate a scenario of recent time accelerating universe dominated by Dark Energy type of fluid. The background matter component of such a universe was considered to…

General Relativity and Quantum Cosmology · Physics 2023-02-06 Subhra Bhattacharya

The existence of 'peculiar' velocities due to the formation of cosmic structure marks a point of discord between the real Universe and the usually assumed Friedmann-Lema\'{i}tre-Robertson-Walker metric which accomodates only the smooth…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-09 Roya Mohayaee , Mohamed Rameez , Subir Sarkar

Using a suite of N-body simulations in different Cold Dark Matter (CDM) scenarios, with cosmological constant (\LCDM) and without (OCDM, SCDM), we study the Hubble flow (\sigh) in Local Volumes (LV) around Local Group (LG) like objects…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Luis A. Martinez-Vaquero , Gustavo Yepes , Yehuda Hoffman , Stefan Gottlöber , Mira Sivan

The nature of dark matter is increasingly constrained by cosmological data. In this paper, we examine the implications of the Cosmic Microwave Background anisotropy limits on the density of cold dark matter under different theoretical…

Astrophysics · Physics 2009-11-07 A. Melchiorri , J. Silk

We examine the cosmic microwave background power spectrum for adiabatic models with a massive neutrino component. We present the results of a detailed numerical evolution of cold + hot dark matter (CHDM) models and compare with the standard…

Astrophysics · Physics 2009-10-28 Scott Dodelson , Evalyn Gates , Albert Stebbins

At large scales and for sufficiently early times, dark matter is described as a pressureless perfect fluid---dust---non-interacting with Standard Model fields. These features are captured by a simple model with two scalars: a Lagrange…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-30 Fabio Capela , Sabir Ramazanov

We examine high-resolution gravitational N-body simulations of the $\Omega=1$ cold dark matter (CDM) model in order to determine whether there is any normalization of the initial density fluctuation spectrum that yields acceptable results…

Astrophysics · Physics 2009-10-22 James M. Gelb , Edmund Bertschinger

The $\Lambda$ Cold Dark Matter model ($\Lambda$CDM) represents the current standard model in cosmology. Within this, there is a tension between the value of the Hubble constant, $H_0$, inferred from local distance indicators and the angular…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Edvard Mörtsell , Suhail Dhawan

Discrepancies have emerged between the predictions of standard cold dark matter (CDM) theory and observations of clustering on sub-galactic scales. Warm dark matter (WDM) is a simple modification of CDM in which the dark matter particles…

Astrophysics · Physics 2009-10-31 Paul Bode , Jeremiah P. Ostriker , Neil Turok

The $\Lambda$CDM model faces several tensions with recent cosmological data and their increased accuracy. The mismatch between the values of the Hubble constant $H_0$ obtained from direct distance ladder measurements and from the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-03 Alain Blanchard , Jean-Yves Héloret , Stéphane Ilić , Brahim Lamine , Isaac Tutusaus

We investigate the imprint of nonlinear matter condensations on the Cosmic Microwave Background (CMB) in an $\Omega=1$, Cold Dark Matter (CDM) model universe. Temperature anisotropies are obtained by numerically evolving matter…

Astrophysics · Physics 2016-08-30 Robin Tuluie , Pablo Laguna

We present results of cosmological N-body hydrodynamic chemistry simulations of primordial structure growth and evolution in a scenario with warm dark matter (WDM) having a mass of 3 keV (thermal relic) and compare with a model consisting…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Umberto Maio , Matteo Viel

The current knowledge of cosmological structure formation suggests that Cold Dark Matter (CDM) halos possess a nonspherical density profile, implying that cosmic structures can be potential sources of gravitational waves via power transfer…

Astrophysics · Physics 2007-05-23 Carmelita Carbone , Carlo Baccigalupi , Sabino Matarrese

Motivated by inflation, the theory of big-bang nucleosynthesis and the quest for a deeper understanding of the fundamental forces and particles, a very successful paradigm for the development of structure in the Universe has evolved. It…

Astrophysics · Physics 2009-10-28 Scott Dodelson , Evalyn Gates , Michael S. Turner

Cosmic microwave background (CMB) anisotropies and density fluctuations are calculated for flat cold dark matter (CDM) models with a wide range of parameters, i.e., $\Omega_0, h$ and $\Omega_B$ for both standard recombination and various…

Astrophysics · Physics 2009-10-22 Naoshi Sugiyama

Nonlocal massive gravity can provide an interesting explanation for the late-time cosmic acceleration, with a dark energy equation of state $w_{\rm DE}$ smaller than $-1$ in the past. We derive the equations of linear cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-11 Savvas Nesseris , Shinji Tsujikawa

A new accelerating cosmology driven only by baryons plus cold dark matter (CDM) is proposed in the framework of general relativity. In this model the present accelerating stage of the Universe is powered by the negative pressure describing…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-06 J. A. S. Lima , J. F. Jesus , F. A. Oliveira

The Cold Dark Matter (CDM) model, wherein the dark matter is treated as a pressureless perfect fluid, provides a good fit to galactic and cosmological data. With the advent of precision cosmology, it should be asked whether this simplest…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-12 Michael Kopp , Constantinos Skordis , Dan B. Thomas

The cosmological tensions present in the $\Lambda$ cold dark matter model that have emerged and strengthened over recent years motivate model independent approaches to analysing data. Cosmography is useful for interpreting data in cosmology…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-26 Morag Hills , Asta Heinesen

We use the Szekeres inhomogeneous relativistic models in order to fit supernova combined data sets. We show that with a choice of the spatial curvature function that is guided by current observations, the models fit the supernova data…