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Related papers: Cosmology: small scale issues revisited

200 papers

The nature of the dark sector of the Universe remains one of the outstanding problems in modern cosmology, with the search for new observational probes guiding the development of the next generation of observational facilities. Clues come…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Hareth Mahdi , Martijn van Beek , Pascal Elahi , Geraint Lewis , Chris Power , Madhura Killedar

The concordance Lambda Cold Dark Matter (Lambda-CDM) model for the formation of structure in the Universe, while remarkably successful at describing observations of structure on large scales, continues to be challenged by observations on…

The cold dark matter (CDM) model has two unsolved issues: simulations overpredict the satellite abundance around the Milky Way (MW) and it disagrees with observations of the central densities of dwarf galaxies which prefer constant density…

Astrophysics of Galaxies · Physics 2015-09-10 Victor H. Robles , V. Lora , T. Matos , F. J. Sanchez-Salcedo

We present a framework for high-redshift ($z \geq 7$) galaxy formation that traces their dark matter (DM) and baryonic assembly in four cosmologies: Cold Dark Matter (CDM) and Warm Dark Matter (WDM) with particle masses of $m_x =$ 1.5, 3…

Astrophysics of Galaxies · Physics 2015-06-17 Pratika Dayal , Andrei Mesinger , Fabio Pacucci

Warm dark matter (WDM) can potentially explain small-scale observations that currently challenge the cold dark matter (CDM) model, as warm particles suppress structure formation due to free-streaming effects. Observing small-scale matter…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-23 Ariane Dekker , Shin'ichiro Ando , Camila A. Correa , Kenny C. Y. Ng

It has been suggested that cold dark matter (CDM) has difficulties in explaining tentative evidence for noncuspy halo profiles in small galaxies, and the low velocity dispersions observed in the largest Milky Way satellites ("too big to…

High Energy Physics - Phenomenology · Physics 2021-07-27 James M. Cline , Zuowei Liu , Guy D. Moore , Wei Xue

Wei et al [PRD 88, 043510 (2013)] have proposed the existence of a cosmological degeneracy between warm dark matter (WDM), modified gravity and coupled cold dark matter (CDM) cosmologies at both the background expansion and the growth of…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-15 Hermano Velten , Humberto A. Borges , Thiago R. P. Caramês

In the standard cosmological model a mysterious cold dark matter (CDM) component dominates the formation of structures. Numerical studies of the formation of CDM halos have produced several robust results that allow unique tests of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Jürg Diemand , Ben Moore

The central densities of dark matter (DM) halos are much lower than predicted in cold DM models of structure formation. Confirmation that they have cores with a finite central density would allow us to rule out many popular types of…

Astrophysics · Physics 2009-10-31 J. A. Sellwood

Recent high-resolution simulations that include Cold Dark Matter (CDM) and baryons have shown that baryonic physics can dramatically alter the dark matter structure of galaxies. These results modify our predictions for observed galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-30 Alyson Brooks

The spatial distribution of Milky Way (MW) subhaloes provides an important set of observables for testing cosmological models. These include the radial distribution of luminous satellites, planar configurations, and the abundance of dark…

Astrophysics of Galaxies · Physics 2023-02-09 Mark R. Lovell , Marius Cautun , Carlos S. Frenk , Wojciech A. Hellwing , Oliver Newton

Cold dark matter simulations appear to disagree with the observations on small distance scales. Here we consider a modified description of CDM particles which is implied by a new fundamental theory: In this picture, the dark matter is…

Astrophysics · Physics 2007-05-23 Antonio R. Mondragon , Roland E. Allen

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

We simulate the formation of a realistic disk galaxy within the hierarchical scenario of structure formation and study its internal properties to the present epoch. We compare results from a LambdaCDM simulation with a LambdaWDM (2keV)…

Astrophysics · Physics 2008-11-26 F. Governato , L. Mayer , J. Wadsley , J. P. Gardner , B. Willman , E. Hayashi , T. Quinn , J. Stadel , G. Lake

The good agreement between large-scale observations and the predictions of the now-standard $\Lambda$CDM theory gives us hope that this will become a lasting foundation for cosmology. After briefly reviewing the current status of the key…

Astrophysics · Physics 2011-08-23 Joel R. Primack

Increasingly stringent limits from LHC searches for new physics, coupled with lack of convincing signals of weakly interacting massive particle (WIMP) in dark matter searches, have tightly constrained many realizations of the standard…

High Energy Physics - Phenomenology · Physics 2015-01-27 Howard Baer , Ki-Young Choi , Jihn E. Kim , Leszek Roszkowski

The leading tensions to the collisionless cold dark matter (CDM) paradigm are the "small-scale controversies", discrepancies between observations at the dwarf-galactic scale and their simulational counterparts. In this work we consider…

Astrophysics of Galaxies · Physics 2020-11-06 Weishuang Linda Xu , Lisa Randall

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

The "Lambda Cold Dark Matter" (LCDM) model of cosmic structure formation is eminently falsifiable: once its parameters are fixed on large scales, it becomes testable in the nearby Universe. Observations within our Local Group of galaxies,…

The cold dark matter halo mass function is much steeper than the galaxy stellar mass function on galactic and subgalactic scales. This difference is usually reconciled by assuming that the galaxy formation efficiency drops sharply with…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Ismael Ferrero , Mario G. Abadi , Julio F. Navarro , Laura V. Sales , Sebastian Gurovich