English
Related papers

Related papers: New predictions from the logotropic model

200 papers

In this letter, we propose a new generalized mass-to-horizon relation to be used in the context of entropic cosmologies and holographic principle scenarios. We show that a general scaling of the mass with the Universe horizon as $M=\gamma…

General Relativity and Quantum Cosmology · Physics 2024-05-02 Hussain Gohar , Vincenzo Salzano

We study the polytropic gas scenario as the unification of dark matter and dark energy. We fit the model parameters by using the latest observational data including type Ia supernovae, baryon acoustic oscillation, cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-01 K. Karami , Z. Safari , S. Asadzadeh

The coupling between dark sectors provides a possible approach to mitigate the coincidence problem of cosmological standard model. In this paper, dark energy is treated as a fluid with a constant equation of state, whose coupling with dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-15 Weiqiang Yang , Lixin Xu

A new dark energy model called "ghost dark energy" was recently suggested to explain the observed accelerating expansion of the universe. This model originates from the Veneziano ghost of QCD. The dark energy density is proportional to…

High Energy Physics - Theory · Physics 2015-03-19 A. Sheykhi , M. Sadegh Movahed

Following the holographic principle, which suggests that the energy density of dark energy may be proportional inversely to the area of the event horizon of the Universe, we have proposed a new energy density of dark energy through the…

General Relativity and Quantum Cosmology · Physics 2023-01-25 H. R. Fazlollahi

We compare the central mass concentration of Cold Dark Matter halos found in cosmological N-body simulations with constraints derived from the Milky Way disk dynamics and from the Tully-Fisher relation. For currently favored values of the…

Astrophysics · Physics 2009-09-28 Julio F. Navarro , Matthias Steinmetz

We use high-resolution cosmological simulations that include the effects of gasdynamics and star formation to investigate the origin of the Tully-Fisher relation in the standard Cold Dark Matter cosmogony. Luminosities are computed for each…

Astrophysics · Physics 2010-04-29 Matthias Steinmetz , Julio Navarro

We explore a model of interacting dark energy where the dark energy density is related by the holographic principle to the Hubble parameter, and the decay of the dark energy into matter occurs at a rate comparable to the current value of…

Astrophysics · Physics 2008-12-18 Micheal S. Berger , Hamed Shojaei

We formulate power-law holographic dark energy, which is a modified holographic dark energy model based on the extended entropy relation arising from the consideration of state mixing between the ground and the excited ones in the…

General Relativity and Quantum Cosmology · Physics 2022-05-25 Eirini C. Telali , Emmanuel N. Saridakis

There are many indications that ordinary matter represents only a tiny fraction of the matter content of the Universe, with the remainder assumed to consist of some different type of matter, which, for various reasons must be nonluminous…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Marcelo Salgado , Daniel Sudarsky , Hernando Quevedo

Despite the many efforts, our theoretical understanding of the ultimate nature of the dark energy component of the universe still lags well behind the astounding experimental evidence achieved from the increasingly sophisticated…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-19 Adria Gomez-Valent , Joan Sola , Spyros Basilakos

In this work a satisfactory, simple theoretical prediction of the data corresponding to observationally (by fine tuning condition) estimated value of the cosmological constant is given. It is supposed (in conceptually analogy with…

Astrophysics · Physics 2007-12-27 Vladan Pankovic , Simo Ciganovic , Jovan Ivanovic , Rade Glavatovic , Petar Grujic

We investigate Dark Energy by associating it with vacuum energy or Cosmological constant ${\Lambda}$ which is taken to be dynamic in nature. Our approach is phenomenological and falls within the domain of variable-$\Lambda$ Cosmology.…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-08 Arkajit Aich

Motivated by results implying that the constituents of dark matter (DM) might be collisional, we consider a cosmological (toy-) model, in which the DM itself possesses some sort of thermodynamic properties. In this case, not only can the…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Kostas Kleidis , Nicholas K. Spyrou

We construct a holographic model for dark energy in the Brans-Dicke cosmology by using the holographic principle considering the Barrow entropy instead of the standard Bekenstein-Hawking one. The former arises from the effort to account for…

General Relativity and Quantum Cosmology · Physics 2025-03-25 S. Ghaffari , G. G. Luciano , S. Capozziello

As is well known, black hole entropy is proportional to the area of the horizon suggesting a holographic principle wherein all degrees of freedom contributing to the entropy reside on the surface. In this note, we point out that large scale…

General Physics · Physics 2013-12-19 C. Sivaram , Kenath Arun

The objective of the present work is to study a cosmological model for a spatially flat Universe whose constituents are a dark energy field and a matter field which includes baryons and dark matter. The constituents are supposed to be in…

General Relativity and Quantum Cosmology · Physics 2013-09-13 Gilberto M. Kremer , Octavio A. S. Sobreiro

The current expansion of the Universe has been observed to be accelerating, and the widely accepted spatially-flat concordance model of general relativistic cosmology attributes this phenomenon to a constant dark energy, a cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-13 Shulei Cao

Based on an analysis of the entropy associated to the vacuum quantum fluctuations, we show that the holographic principle, applied to the cosmic scale, constitutes a possible explanation for the observed value of the cosmological constant,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Saulo Carneiro

We propose a dark energy model with a logarithmic cosmological fluid which can result in a very small current value of the dark energy density and avoid the coincidence problem without much fine-tuning. We construct a couple of dynamical…

General Relativity and Quantum Cosmology · Physics 2014-07-30 Seyen Kouwn , Phillial Oh