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Related papers: Cosmic structure sizes in generic dark energy mode…

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We consider the phantom braneworld model in the context of the maximum turn around radius, $R_{\rm TA,max}$, of a stable, spherical cosmic structure with a given mass. The maximum turn around radius is the point where the attraction due to…

General Relativity and Quantum Cosmology · Physics 2017-11-15 Sourav Bhattacharya , Stefanos R Kousvos

The maximum size of a cosmic structure is given by the maximum turnaround radius -- the scale where the attraction due to its mass is balanced by the repulsion due to dark energy. We derive generic formulae for the estimation of the maximum…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-17 Sourav Bhattacharya , Konstantinos F. Dialektopoulos , Antonio Enea Romano , Constantinos Skordis , Theodore N. Tomaras

The maximum size of a bound cosmic structure is computed perturbatively as a function of its mass in the framework of the cubic galileon, proposed recently to model the dark energy of our Universe. Comparison of our results with…

General Relativity and Quantum Cosmology · Physics 2016-05-20 Sourav Bhattacharya , Konstantinos F. Dialektopoulos , Theodore N. Tomaras

The accelerating behavior of cosmic fluid opposes to the gravitational attraction, at present epoch, whereas standard gravity is dominant at small scales. As a consequence, there exists a \emph{point} where the effects are counterbalanced,…

General Relativity and Quantum Cosmology · Physics 2019-02-20 Salvatore Capozziello , Konstantinos F. Dialektopoulos , Orlando Luongo

Three simple idealised models are studied in order to develop some intuition about the leading order effect of non-sphericity on the maximum turnaround size $R_{\rm TA,max}$ of large scale bound cosmic structures. Two of them describe…

General Relativity and Quantum Cosmology · Physics 2021-03-09 Sourav Bhattacharya , Theodore N Tomaras

The requirement that their gravitational binding self-energy density must at least equal the background repulsive dark energy density for large scale cosmic structures implies a mass-radius relation of M/R^2 ~ 1g/cm^2, as pointed out…

General Physics · Physics 2018-06-21 Louise Rebecca , Kenath Arun , C Sivaram

For a general dark-energy equation of state, we estimate the maximum possible radius of massive structures that are not destabilized by the acceleration of the cosmological expansion. A comparison with known stable structures constrains the…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-16 V. Pavlidou , N. Tetradis , T. N. Tomaras

We find that if we live at the center of an inhomogeneity with total density contrast of roughly 0.1, dark energy is not a cosmological constant at 95% confidence level. Observational constraints on the equation of state of dark energy, w,…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-17 Valerio Marra , Mikko Pääkkönen , Wessel Valkenburg

The turnaround radius of a large structure in an accelerating universe has been studied only for spherical structures, while real astronomical systems deviate from spherical symmetry. We show that, for small deviations from spherical…

General Relativity and Quantum Cosmology · Physics 2019-07-16 Andrea Giusti , Valerio Faraoni

There is now strong evidence that the current energy density of the Universe is dominated by dark energy with an equation of state w<-1/3, which is causing accelerated expansion. The build-up of structure within such Universes is subject to…

Astrophysics · Physics 2008-11-26 Will J. Percival

In $\Lambda$CDM cosmology, structure formation is halted shortly after dark energy dominates the mass/energy budget of the Universe. A manifestation of this effect is that in such a cosmology the turnaround radius has an upper bound.…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Dimitrios Tanoglidis , Vasiliki Pavlidou , Theodore Tomaras

We review the current status of cosmological parameters, dark energy and large-scale structure, from a theoretical and observational perspective. We first present the basic cosmological parameters and discuss how they are measured with…

Astrophysics · Physics 2007-05-23 S. E. Deustua , R. Caldwell , P. Garnavich , L. Hui , A. Refregier

Our intuitive understanding of cosmic structure formation works best in scales small enough so that bound, relaxed gravitating systems are no longer adjusting their radius; and large enough so that space and matter follow the average…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Vasiliki Pavlidou , Theodore N. Tomaras

In many cosmological models, including the $\Lambda$CDM concordance model, there exist a theoretical upper bounds on the size of collapsing structures. The most common formulations in the literature refer to a turnaround radius in spherical…

General Relativity and Quantum Cosmology · Physics 2022-05-11 Jan J. Ostrowski , Ismael Delgado Gaspar

The gravitational instability, responsible for the formation of the structure of the Universe, occurs below energy thresholds and above spatial scales of a self-gravitating expanding region, when thermal energy can no longer counterbalance…

General Relativity and Quantum Cosmology · Physics 2019-01-04 Zacharias Roupas

We use N-body simulations to examine whether a characteristic turnaround radius, as predicted from the spherical collapse model in a $\rm {\Lambda CDM}$ Universe, can be meaningfully identified for galaxy clusters, in the presence of full…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-28 Giorgos Korkidis , Vasiliki Pavlidou , Konstantinos Tassis , Evangelia Ntormousi , Theodore N. Tomaras , Konstantinos Kovlakas

We present cosmological constraints arising from the first measurement of the radial (line-of-sight) baryon acoustic oscillations (BAO) scale in the large scale structure traced by the galaxy distribution. Here we use these radial BAO…

Astrophysics · Physics 2009-09-02 Enrique Gaztanaga , Ramon Miquel , Eusebio Sanchez

Constraints on the expansion history of the universe from measurements of cosmological distances make predictions for large-scale structure growth. Since these predictions depend on assumptions about dark energy evolution and spatial…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-21 Michael J. Mortonson

The fact that the energy densities of dark energy and matter are similar currently, known as the coincidence problem, is one of the main unsolved problems of cosmology. We present here a model in which a spatial curvature of the universe…

Astrophysics · Physics 2009-11-13 Urbano Franca

The evolution of scalar perturbations is studied for 2-component (non-relativistic matter and dark energy) cosmological models at the linear and non-linear stages. The dark energy is assumed to be the scalar field with either classical or…

Astrophysics · Physics 2015-05-13 O. Sergijenko , Yu. Kulinich , B. Novosyadlyj , V. Pelykh
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