Spherical collapse and cluster number counts in dark energy models disformally coupled to dark matter

Several independent cosmological tests have shown evidences that the energy density of the universe is dominated by a dark energy component, which causes the present accelerated expansion. The large scale structure formation can be used to probe dark energy models, and the mass function of dark matter haloes is one of the best statistical tools to perform this study. We present here a statistical analysis of mass functions of galaxies under a homogeneous dark energy model, proposed in the work of Percival (2005), using an observational flux-limited X-ray cluster survey, and CMB data from WMAP. We compare, in our analysis, the standard Press–Schechter (PS) approach (where a Gaussian distribution is used to describe the primordial density fluctuation field of the mass function), and the PL (power–law) mass function (where we apply a non-extensive q-statistical distribution to the primordial density field). We conclude that the PS mass function cannot explain at the same time the X-ray and the CMB data (even at 99% confidence level), and the PS best fit dark energy equation of state parameter is ω = -0.58, which is distant from the cosmological constant case. The PL mass function provides better fits to the HIFLUGCS X-ray galaxy data and the CMB data; we also note that the ω parameter is very sensible to modifications in the PL free parameter, q, suggesting that the PL mass function could be a powerful tool to constrain dark energy models.

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Relieving the tension between weak lensing and cosmic microwave background with interacting dark matter and dark energy models

Journal of Cosmology and Astroparticle Physics ◽

10.1088/1475-7516/2018/02/038 ◽

2018 ◽

Vol 2018 (02) ◽

pp. 038-038 ◽

Cited By ~ 22

Author(s):

Rui An ◽

Chang Feng ◽

Bin Wang

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Cosmic Microwave Background ◽

Weak Lensing ◽

Microwave Background ◽

Energy Models

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Addressing the high-f problem in pseudo-Nambu–Goldstone boson dark energy models with dark matter–dark energy interaction

The European Physical Journal C ◽

10.1140/epjc/s10052-020-08457-y ◽

2020 ◽

Vol 80 (10) ◽

Author(s):

Upala Mukhopadhyay ◽

Avik Paul ◽

Debasish Majumdar

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Dark Energy Model ◽

Goldstone Boson ◽

The Other ◽

Mass Limit ◽

Energy Models ◽

Energy Interaction ◽

Energy Scenario ◽

Type Potential

AbstractWe consider a dark energy scenario driven by a scalar field $$\phi $$ ϕ with a pseudo-Nambu–Goldstone boson (pNGB) type potential $$V(\phi )=\mu ^4 \left( 1+ \mathrm{cos}(\phi /f) \right) $$ V ( ϕ ) = μ 4 1 + cos ( ϕ / f ) . The pNGB originates out of breaking of spontaneous symmetry at a scale f close to Planck mass $$M_\mathrm{{pl}}$$ M pl . We consider two cases namely the quintessence dark energy model with pNGB potential and the other, where the standard pNGB action is modified by the terms related to Slotheon cosmology. We demonstrate that for this pNGB potential, high-f problem is better addressed when the interaction between dark matter and dark energy is taken into account and that Slotheon dark energy scenario works even better over quintessence in this respect. To this end, a mass limit for dark matter is also estimated.

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Forecasting the interaction in dark matter-dark energy models with standard sirens from the Einstein telescope

Journal of Cosmology and Astroparticle Physics ◽

10.1088/1475-7516/2020/05/021 ◽

2020 ◽

Vol 2020 (05) ◽

pp. 021-021 ◽

Cited By ~ 5

Author(s):

Riis R.A. Bachega ◽

André A. Costa ◽

E. Abdalla ◽

K.S.F. Fornazier

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Energy Models ◽

Einstein Telescope

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Pilgrim dark energy models in fractal universe

International Journal of Modern Physics D ◽

10.1142/s0218271817500493 ◽

2016 ◽

Vol 26 (06) ◽

pp. 1750049 ◽

Cited By ~ 2

Author(s):

Abdul Jawad ◽

Shamaila Rani ◽

Ines G. Salako ◽

Faiza Gulshan

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Cold Dark Matter ◽

Accelerated Expansion ◽

Freezing And Thawing ◽

Eos Parameter ◽

Pilgrim Dark Energy ◽

Energy Models ◽

Expansion Behavior ◽

The Universe

We discuss the cosmological implications of interacting pilgrim dark energy (PDE) models (with Hubble, Granda–Oliveros and generalized ghost cutoffs) with cold dark matter ([Formula: see text]CDM) in fractal cosmology by assuming the flat universe. We observe that the Hubble parameter lies within observational suggested ranges while deceleration parameter represents the accelerated expansion behavior of the universe. The equation of state (EoS) parameter ([Formula: see text]) corresponds to the quintessence region and phantom region for different cases of [Formula: see text]. Further, we can see that [Formula: see text]–[Formula: see text] (where prime indicates the derivative with respect to natural logarithmic of scale factor) plane describes the freezing and thawing regions and also corresponds to [Formula: see text] limit for some cases of [Formula: see text] (PDE parameter). It is also noted that the [Formula: see text]–[Formula: see text] (state-finder parameters) plane corresponds to [Formula: see text] limit and also shows the Chaplygin as well as phantom/quintessence behavior. It is observed that pilgrim dark energy models in fractal cosmology expressed the consistent behavior with recent observational schemes.

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ACCELERATION AND DECELERATION IN THE CURVATURE-INDUCED PHANTOM MODEL OF THE LATE AND FUTURE UNIVERSE: COSMIC COLLAPSE AND ITS QUANTUM ESCAPE

International Journal of Modern Physics D ◽

10.1142/s0218271809014819 ◽

2009 ◽

Vol 18 (05) ◽

pp. 865-887

Author(s):

S. K. SRIVASTAVA ◽

J. DUTTA

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Quantum Gravity ◽

Cosmological Constant ◽

Early Universe ◽

High Energy ◽

High Energy Density ◽

Energy Models ◽

Acceleration And Deceleration ◽

The Universe

In this paper, the cosmology of the late and future universe is obtained from f(R) gravity with nonlinear curvature terms R2 and R3 (R is the Ricci scalar curvature). It is different from f(R) dark energy models where nonlinear curvature terms are taken as a gravitational alternative to dark energy. In the present model, neither linear nor nonlinear curvature terms are taken as dark energy. Rather, dark energy terms are induced by curvature terms and appear in the Friedmann equation derived from f(R) gravitational equations. This approach has an advantage over f(R) dark energy models in three ways: (i) results are consistent with WMAP observations, (ii) dark matter is produced from the gravitational sector and (iii) the universe expands as ~ t2/3 during dominance of the curvature-induced dark matter, which is consistent with the standard cosmology. Curvature-induced dark energy mimics phantom and causes late acceleration. It is found that transition from matter-driven deceleration to acceleration takes place at the redshift 0.36 at time 0.59 t0 (t0 is the present age of the universe). Different phases of this model, including acceleration and deceleration during the phantom phase, are investigated. It is found that expansion of the universe will stop at the age of 3.87 t0 + 694.4 kyr. After this epoch, the universe will contract and collapse by the time of 336.87 t0 + 694.4 kyr. Further, it is shown that cosmic collapse obtained from classical mechanics can be avoided by making quantum gravity corrections relevant near the collapse time due to extremely high energy density and large curvature analogous to the state of the very early universe. Interestingly, the cosmological constant is also induced here; it is extremely small in the classical domain but becomes very high in the quantum domain. This result explains the largeness of the cosmological constant in the early universe due to quantum gravity effects during this era and its very low value in the present universe due to negligible quantum effect in the late universe.

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TOWARDS CLASSIFICATION OF SIMPLE DARK ENERGY COSMOLOGICAL MODELS

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887807002016 ◽

2007 ◽

Vol 04 (02) ◽

pp. 313-323 ◽

Cited By ~ 6

Author(s):

MAREK SZYDLOWSKI ◽

ALEKSANDRA KUREK

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Cold Dark Matter ◽

Friedmann Equation ◽

Chaplygin Gas ◽

Generalized Chaplygin Gas ◽

Cosmological Time ◽

Energy Models ◽

State Formula ◽

The Universe

We characterize a class of simple FRW models filled by both dark energy and dark matter in notion of a single potential function of the scale factor a(t); t is the cosmological time. It represents the potential of a fictitious particle — Universe moving in 1-dimensional well V(a) which the positional variable mimics the evolution of the Universe. Then the class of all dark energy models (called a multiverse) can be regarded as a Banach space naturally equipped in the structure of the Sobolev metric. In this paper, we explore the notion of C1 metric introduced in the multiverse which measures distance between any two dark energy models. If we choose cold dark matter as a reference, then we can find how far apart are different models offering explanation of the present accelerating expansion phase of the Universe. We consider both models with dark energy (models with the generalized Chaplygin gas, models with variable coefficient equation of state [Formula: see text] parameterized by redshift z, models with phantom matter) as well as models based on some modification of Friedmann equation (Cardassian models, Dvali–Gabadadze–Porrati brane models). We argue that because observational data still favor the ΛCDM model, all reasonable dark energy models should belong to the nearby neighborhood of this model.

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Interacting dynamical dark energy with stable high-scale cosmological perturbations at radiation-dominated epoch

Modern Physics Letters A ◽

10.1142/s0217732321501546 ◽

2021 ◽

pp. 2150154

Author(s):

Roman Neomenko

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Coupling Parameter ◽

Gravitational Interaction ◽

State Parameter ◽

Model Parameters ◽

Cosmological Perturbations ◽

Energy Models ◽

The Impact ◽

Dynamical Dark Energy

In this paper, the cosmological perturbations of dynamical dark energy and dark matter, which interact non-gravitationally are studied. This dark energy–dark matter non-gravitational interaction is linearly dependent on the energy densities of dark components. However, in the interacting quintessence dark energy models with such type of interaction, the non-adiabatic instabilities of cosmological perturbations at radiation-dominated epoch arise. To avoid this problem, the model of dynamical dark energy was chosen as the basis. Here, the equation of state parameter of dark energy evolves in time but can be assumed constant at early epoch, so this model can be tuned in such a way that the non-adiabatic instabilities would not appear. The drawback of this cosmological model is that the energy densities of dark components can take the negative values for the certain range of interaction parameter, so the conditions for positivity of dark components densities were derived. Using obtained constraints on the model parameters, the impact of coupling parameter on modification of cosmological perturbations’ evolution is analyzed.

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