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Recent detection of high-redshift, massive clusters through Sunyaev-Zel'dovich observations has opened up a new way to test cosmological models. It is known that detection of a single supermassive cluster at a very high redshift can rule…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-22 Arman Shafieloo , George F. Smoot

The idea of a negative-pressure dark energy component in the Universe which causes an accelerated expansion in the late Universe has deep implications in models of field theory and general relativity. In this article, we survey the evidence…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 Arindam Mazumdar , Subhendra Mohanty , Priyank Parashari

The $\Lambda$CDM model of structure formation makes strong predictions on concentration and shape of DM (dark matter) halos, which are determined by mass accretion processes. Comparison between predicted shapes and observations provides a…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Mauro Sereno , Keiichi Umetsu , Stefano Ettori , Jack Sayers , I-Non Chiu , Massimo Meneghetti , Jesús Vega-Ferrero , Adi Zitrin

(Abridged) A simple six-parameter LCDM model provides a successful fit to WMAP data, both when the data are analyzed alone and in combination with other cosmological data. Even so, it is appropriate to search for any hints of deviations…

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

We study the clustering properties of galaxy clusters expected to be observed by various forthcoming surveys both in the X-ray and sub-mm regimes by the thermal Sunyaev-Zel'dovich effect. Several different background cosmological models are…

Astrophysics · Physics 2014-11-18 C. Fedeli , L. Moscardini , M. Bartelmann

The conventional cold, particle interpretation of dark matter (CDM) still lacks laboratory support and struggles with the basic properties of common dwarf galaxies, which have surprisingly uniform central masses and shallow density…

Astrophysics of Galaxies · Physics 2014-06-26 Hsi-Yu Schive , Tzihong Chiueh , Tom Broadhurst

A recent study has claimed that the rotation curve shapes and mass densities of Low Surface Brightness (LSB) galaxies are largely consistent with $\Lambda$CDM predictions, in contrast to a large body of observational work. I demonstrate…

Astrophysics · Physics 2009-11-13 W. J. G. de Blok

In the very last years, cosmological models where the properties of the dark components of the Universe - dark matter and dark energy - are accounted for by a single "dark fluid" have drawn increasing attention and interest. Amongst many…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-02 Stefano Camera , Carmelita Carbone , Lauro Moscardini

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'

Voids are dominant features of the cosmic web. We revisit the cosmological information content of voids and connect void properties with the parameters of the background universe. We combine analytical results with a suite of large n-body…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-24 Benjamin C. Bromley , Margaret J. Geller

An analysis of voids using cosmological N-body simulations of cold dark matter models is presented. It employs a robust statistics of voids, that was recently applied to discriminate between data from the Las Campanas Redshift Survey and…

Astrophysics · Physics 2009-11-07 S. Arbabi-Bidgoli , V. Mueller

The alignment of clusters of galaxies with their nearest neighbours and between clusters within a supercluster is investigated using simulations of 512^{3} dark matter particles for \LambdaCDM and \tauCDM cosmological models. Strongly…

Astrophysics · Physics 2009-10-31 L. I. Onuora , P. A. Thomas

We investigate the spatial distribution of galactic satellites in high resolution simulations of structure formation in the LCDM model: the Aquarius dark matter simulations of individual halos and the Millennium II simulation of a large…

Astrophysics of Galaxies · Physics 2015-06-05 Jie Wang , Carlos S. Frenk , Andrew P. Cooper

The main foundations of the standard $\Lambda $CDM model of cosmology are that: 1) The redshifts of the galaxies are due to the expansion of the Universe plus peculiar motions; 2) The cosmic microwave background radiation and its…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Martin Lopez-Corredoira

Observations of the cosmic microwave backgroundradiation are described to remarkable accuracy by the six-parameterLambda CDM cosmology. However, the key ingredients of this model, namely dark matter, dark energy and cosmic inflation are not…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-15 George Efstathiou

Dark energy is a fundamental constituent of our universe, its status in the cosmological field equation should be equivalent to that of gravity. Here we construct a dark energy and matter gravity coupling (DEMC) model of cosmology in a way…

General Physics · Physics 2015-01-14 Ti-Pei Li

We use a cosmological simulation of the Local Group to make quantitative and speculative predictions for direct detection experiments. Cold dark matter (CDM) halos form via a complex series of mergers, accretion events and violent…

Observations on galactic scales seem to be in contradiction with recent high resolution N-body simulations. This so-called cold dark matter (CDM) crisis has been addressed in several ways, ranging from a change in fundamental physics by…

Astrophysics · Physics 2009-11-06 Alexander Knebe , Julien Devriendt , Asim Mahmood , Joseph Silk

The standard cold dark matter (CDM) model predicts too many and too dense small structures. We consider an alternative model that the dark matter undergoes two-body decays with cosmological lifetime $\tau$ into only one type of massive…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-04 Dalong Cheng , M. -C. Chu , Jiayu Tang