中文
相关论文

相关论文: Turnaround radius in $\Lambda$CDM, and dark matter…

200 篇论文

Based on flat Friedmann-Robertson Walker cold dark matter (CDM) type models driven by non-relativistic matter and an exotic fluid (quintessence) with an equation of state: $p_{Q}=w\rho_{Q}$ ($-1\le w<0$), we investigate whether or not the…

天体物理学 · 物理学 2009-11-07 S. Basilakos

The shape and diversity of dwarf galaxy rotation curves is at apparent odds with dark matter halos in a $\Lambda$ Cold Dark Matter ($\Lambda$CDM) cosmology. We use mock data from isolated dwarf galaxy simulations to show that this owes to…

星系天体物理 · 物理学 2016-09-07 J. I. Read , G. Iorio , O. Agertz , F. Fraternali

The standard LambdaCDM model of cosmology is usually understood to arise from demanding that the Friedmann-Lemaitre-Robertson-Walker (FLRW) metric satisfy the General Relativity dynamics for spacetime metrics. The FLRW data-based dominant…

综合物理 · 物理学 2009-07-13 Reginald T Cahill

We present a new statistics based on the turn-around radii of cluster halos to break the dark sector degeneracy between the $\Lambda$CDM model and the alternative ones with $f(R)$ gravity and massive neutrinos ($\nu$) characterized by the…

宇宙学与河外天体物理 · 物理学 2022-11-07 Jounghun Lee , Marco Baldi

The turn-around radii of the galaxy groups show the imprint of a long battle between their self-gravitational forces and the accelerating space. The standard $\Lambda$CDM cosmology based on the general relativity (GR) predicts the existence…

宇宙学与河外天体物理 · 物理学 2017-06-21 Jounghun Lee , Baojiu Li

We investigate the luminosity-temperature ($L$-$T$) relation of galaxy clusters as a probe for testing modified gravity (MG) theories, focusing on $f(R)$ gravity and symmetron models. Using an improved semi-analytic framework that…

宇宙学与河外天体物理 · 物理学 2026-03-31 Antonino Del Popolo , Saeed Fakhry , David F. Mota

We extended the modified Lemaitre-Tolman model taking into account the effect of angular momentum and dynamical friction. The inclusion of these quantities in the equation of motion modifies the evolution of a perturbation, initially moving…

宇宙学与河外天体物理 · 物理学 2021-03-24 Antonino Del Popolo , Maksym Deliyergiyev , Man Ho Chan

We investigate the turnaround radius of the Reissner-Nordstr\"{o}m deSitter Spacetime and how the turnaround radius changes if a test particle carries charge. We also consider the Mart\'{i}nez-Troncoso-Zanelli (MTZ) solution of conformally…

广义相对论与量子宇宙学 · 物理学 2024-05-22 Ethan James German , Joseph Sultana

The mass discrepancy acceleration relation (MDAR) describes the coupling between baryons and dark matter (DM) in galaxies: the ratio of total-to-baryonic mass at a given radius anti-correlates with the acceleration due to baryons. The MDAR…

星系天体物理 · 物理学 2016-01-27 Arianna Di Cintio , Federico Lelli

Among many models which can describe the bouncing cosmology, A matter bounce scenario that is deformed by a running vacuum model of dark energy (RVM-DE) has been interested. In this research, I show that a class of RVM-CDM (cold dark…

广义相对论与量子宇宙学 · 物理学 2022-09-13 A. Khodam-Mohammadi

We explain the effect of dark matter (flat rotation curve) using modified gravitational dynamics. We investigate in this context a low energy limit of generalized general relativity with a nonlinear Lagrangian ${\cal L}\propto R^n$, where…

天体物理学 · 物理学 2008-11-26 Andrzej Borowiec , Wlodzimierz Godlowski , Marek Szydlowski

Following an existing procedure in general relativity, the turnaround radius of a spherical structure is studied in scalar-tensor gravity using a new prescription for the analog of the Hawking-Hayward quasilocal mass in this class of…

广义相对论与量子宇宙学 · 物理学 2020-08-12 Valerio Faraoni , Andrea Giusti , Jeremy Côté

We derive the mass-temperature relation using an improved top-hat model and a continuous formation model which takes into account the effects of the ordered angular momentum acquired through tidal-torque interaction between clusters, random…

宇宙学与河外天体物理 · 物理学 2019-08-21 Antonino Del Popolo , Francesco Pace , David F. Mota

For the first time, we analyze the impact of dark matter (DM) on the curvature properties of quarkyonic neutron stars (NS) using a hybrid model based on quarkyonic-effective field theory within the relativistic mean-field (E-RMF) framework.…

高能天体物理现象 · 物理学 2025-01-22 Jeet Amrit Pattnaik , D. Dey , R. N. Panda , M. Bhuyan , S. K. Patra

We use the spherical collapse model to demonstrate that the observable average density of virialized clusters depends on the properties of dark energy along with the properties of gravity on cluster scales and can therefore be used as a…

宇宙学与河外天体物理 · 物理学 2023-08-23 Evangelos A. Paraskevas , Leandros Perivolaropoulos

We consider a recently proposed model in which dark matter interacts with a thermal background of dark radiation. Dark radiation consists of relativistic degrees of freedom which allow larger values of the expansion rate of the universe…

宇宙学与河外天体物理 · 物理学 2018-01-24 Manuel A. Buen-Abad , Martin Schmaltz , Julien Lesgourgues , Thejs Brinckmann

Cosmography can be considered as a sort of a model-independent approach to tackle the dark energy/modified gravity problem. In this review, the success and the shortcomings of the $\Lambda$CDM model, based on General Relativity and standard…

广义相对论与量子宇宙学 · 物理学 2019-04-09 Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

We study the late time cosmological evolution of $f(R)$ theories of modified gravity, with the matter content of the universe being that of collisional self interacting matter. We assume that the universe is described by a flat…

广义相对论与量子宇宙学 · 物理学 2015-06-22 V. K. Oikonomou , N. Karagiannakis

In this work we study a relativistic mean-field (RMF) hadronic model, with nucleonic short-range correlations (SRC) included, coupled to dark matter (DM) through the Higgs boson. We study different parametrizations of this model by running…

核理论 · 物理学 2023-11-30 M. Dutra , C. H. Lenzi , O. Lourenço

We analyse f(R) modifications of Einstein's gravity as dark energy models in the light of their connection with chameleon theories. Formulated as scalar-tensor theories, the f(R) theories imply the existence of a strong coupling of the…

天体物理学 · 物理学 2009-02-23 Philippe Brax , Carsten van de Bruck , Anne-Christine Davis , Douglas J. Shaw