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Related papers: The effective fluid approach for modified gravity

200 papers

Lattice Boltzmann method models offer a novel framework for the simulation of high Reynolds number dilute gravity currents. The numerical algorithm is well suited to acceleration via implementation on massively parallel computer…

The standard paradigm of cosmology assumes General Relativity (GR) is a valid theory for gravity at scales in which it has not been properly tested. Developing novel tests of GR and its alternatives is crucial if we want to give strength to…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-22 Claudio Llinares

We provide a systematic and updated discussion of a research line carried out by our group over the last few years, in which gravity is modified at cosmological distances by the introduction of nonlocal terms, assumed to emerge at an…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Enis Belgacem , Yves Dirian , Andreas Finke , Stefano Foffa , Michele Maggiore

We use the ideas of entropic gravity to derive the FRW cosmological model and show that for late time evolution we have an effective cosmological constant. By using the first law of thermodynamics and the modified entropy area relationship…

General Relativity and Quantum Cosmology · Physics 2018-06-15 I. Díaz-Saldaña , J. López-Domínguez , M. Sabido

A reconstruction of modified gravity is proposed by establishing a correspondence between the effective density of the modified gravity and the holographic density. The non-homogeneous term in the modified Friedmann equation, generated by…

General Relativity and Quantum Cosmology · Physics 2019-02-20 L. N. Granda

Large scale structure surveys will likely become the next leading cosmological probe. In our universe, matter perturbations are large on short distances and small at long scales, i.e. strongly coupled in the UV and weakly coupled in the IR.…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-17 John Joseph M. Carrasco , Mark P. Hertzberg , Leonardo Senatore

We propose a hybrid model, coupling Lattice Boltzmann and Molecular Dynamics models, for the simulation of dense fluids. Time and length scales are decoupled by using an iterative Schwarz domain decomposition algorithm. The MD and LB…

Soft Condensed Matter · Physics 2015-06-25 A. Dupuis , E. M. Kotsalis , P. Koumoutsakos

We use anisotropic fluid cosmology to describe the present, dark energy-dominated, universe. Similarly to what has been proposed for galactic dynamics, the anisotropic fluid gives an effective description of baryonic matter, dark energy and…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Mariano Cadoni , Andrea P. Sanna , Matteo Tuveri

The subject of this paper is to investigate the weak regime covariant scalar-tensor-vector gravity (STVG) theory, known as the MOdified gravity (MOG) theory of gravity. First, we show that the MOG in the absence of scalar fields is…

General Relativity and Quantum Cosmology · Physics 2018-10-09 M. Khurshudyan , N. S. Mazhari , D. Momeni , R. Myrzakulov , M. Raza

We present a cosmological model constituted by three perfect fluids, cold dark matter, vacuum energy and radiation, which interacting with each other lead to an equivalent model of three self-preserved fluids that can be identified with the…

General Relativity and Quantum Cosmology · Physics 2018-01-25 Mónica Forte

Using the fluid representation, we formulate the conditions for the appearance of all four types finite-time future singularity in modified gravity in accelerating FRW universe. It stressed that number of standard quintessence/phantom DE…

High Energy Physics - Theory · Physics 2014-11-20 Shin'ichi Nojiri , Sergei D. Odintsov

Theoretical differences in the growth of structure offer the possibility that we might distinguish between modified gravity theories of dark energy and \LambdaCDM. A significant impediment to applying current and prospective large scale…

Astrophysics · Physics 2008-11-26 Istvan Laszlo , Rachel Bean

We introduce mochi_class, an extension of the Einstein-Boltzmann solver hi_class, designed to unlock the full phenomenological potential of Horndeski gravity. This extension allows for general input functions of time without the need for…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-10 Matteo Cataneo , Emilio Bellini

We present the data-driven reconstruction of gravitational theories and Dark Energy models on cosmological scales. We showcase the power of present cosmological probes at constraining these models and quantify the knowledge of their…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Marco Raveri

We investigate the possibility that part of the dark matter is not made out of the usual cold dark matter (CDM) dustlike particles, but is under the form of a fluid of strings with barotropic factor $w_s = -1/3$ of cosmic origin. To this…

Astrophysics · Physics 2009-11-11 S. Capozziello , V. F. Cardone , G. Lambiase , A. Troisi

Gravitational collapse of a spherically symmetric homogeneous perfect barotropic fluid with linear as well as polytropic type Equation of State (EoS) has been investigated in the framework of a linear model of $f(R,T)$ gravity. This…

General Relativity and Quantum Cosmology · Physics 2020-05-06 Karim Mosani , Gauranga C. Samanta

Modifications of general relativity provide an alternative explanation to dark energy for the observed acceleration of the universe. We review recent developments in modified gravity theories, focusing on higher dimensional approaches and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Bhuvnesh Jain , Justin Khoury

In Friedman-Robertson-Walker flat spacetime, we consider a three fluid cosmological model which contains dark matter, dark energy and baryonic matter in the form of perfect fluid with a barotropic equation of state. Dark matter is taken in…

General Relativity and Quantum Cosmology · Physics 2015-12-23 Nilanjana Mahata , Subenoy Chakraborty

We check the dynamical and observational features of four typologies of logotropic dark energy models, leading to a \emph{thermodynamic cosmic speed up} fueled by a single fluid that unifies dark energy and dark matter. We first present two…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-03 Kuantay Boshkayev , Talgar Konysbayev , Orlando Luongo , Marco Muccino , Francesco Pace

A spherically symmetric comoving fluid solution of Einstein's equations is adapted for cosmological application by extending the geometry of standard FRW cosmology using a generalised curvature term. The resulting model retains many of the…

General Relativity and Quantum Cosmology · Physics 2009-09-15 Ron Wiltshire
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