English
Related papers

Related papers: Why Newton's gravity is practically reliable in th…

200 papers

We present the leading order non-linear density and velocity power spectra in the complete form; previous studies have omitted the vector- and tensor-type perturbations simultaneously excited by the scalar-type perturbation in nonlinear…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-22 Jai-chan Hwang , Donghui Jeong , Hyerim Noh

We develop a formalism for General Relativistic N-body simulations in the weak field regime, suitable for cosmological applications. The problem is kept tractable by retaining the metric perturbations to first order, the first derivatives…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-17 Julian Adamek , David Daverio , Ruth Durrer , Martin Kunz

Relativistic cosmological perturbation analyses can be made based on several different fundamental gauge conditions. In the pressureless limit the variables in certain gauge conditions show the correct Newtonian behaviors. We consider the…

Astrophysics · Physics 2007-05-23 J. Hwang , H. Noh

Versions of parameterized pseudo-Newtonian gravity theories specially designed for cosmology have been introduced in recent cosmology literature. The modifications demand a zero-pressure fluid in the context of versions of modified…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jai-chan Hwang , Hyerim Noh , Chan-Gyung Park

$f(R)$ gravity is one of the simplest theories of modified gravity to explain the accelerated cosmic expansion. Although it is usually assumed that the quasi-Newtonian approach (a combination of the quasi-static approximation and sub-Hubble…

General Relativity and Quantum Cosmology · Physics 2015-12-02 Mu-Chen Chiu , Andy Taylor , Chenggang Shu , Hong Tu

The post-Newtonian (PN) approximation, based on the assumptions of weak gravitational fields and slow motions, provides a way to estimate general relativistic effects in the fully nonlinear evolution stage of the large-scale cosmic…

Astrophysics · Physics 2011-03-28 Jai-chan Hwang , Hyerim Noh , Dirk Puetzfeld

We derive the basic equations of the cosmological first-order post-Newtonian approximation from the recently formulated fully nonlinear and exact cosmological perturbation theory in Einstein's gravity. Apparently the latter, being exact,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Hyerim Noh , Jai-chan Hwang

We present the growing mode solutions of cosmological perturbations to the second order in the matter dominated era. We also present several gauge-invariant combinations of perturbation variables to the second order in most general fluid…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jai-chan Hwang , Hyerim Noh , Jinn-Ouk Gong

In this paper we lay down the foundations for a purely Newtonian theory of cosmology, valid at scales small compared with the Hubble radius, using only Newtonian point particles acted on by gravity and a possible cosmological term. We…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-05 Gary W Gibbons , George F R Ellis

The standard numerical tools for studying non-linear collapse of matter are Newtonian $N$-body simulations. Previous work has shown that these simulations are in accordance with General Relativity (GR) up to first order in perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-07 Christian Fidler , Thomas Tram , Cornelius Rampf , Robert Crittenden , Kazuya Koyama , David Wands

Effects from nonstandard corrections to Newtonian gravity, at large scale, can be investigated using the cosmological structure formation. In particular, it is possible to show if and how a logarithmic correction (as that induced from…

General Relativity and Quantum Cosmology · Physics 2021-07-29 Salvatore Capozziello , Mir Faizal , Mir Hameeda , Behnam Pourhassan , Vincenzo Salzano

We present the generalization of a recently introduced modified gravitational potential for self-gravitating fluids. The use of this potential allows for an accurate approximation of general relativistic effects in an otherwise Newtonian…

Astrophysics · Physics 2009-11-13 Bernhard Mueller , Harald Dimmelmeier , Ewald Mueller

We derive the effects of a non-zero cosmological constant $\Lambda$ on gravitational wave propagation in the linearized approximation of general relativity. In this approximation we consider the situation where the metric can be written as…

High Energy Physics - Theory · Physics 2012-09-17 José Bernabeu , Domènec Espriu , Daniel Puigdomènech

General relativistic cosmology cannot be reduced to linear relativistic perturbations superposed on an isotropic and homogeneous (Friedmann-Robertson-Walker) background, even though such a simple scheme has been successfully applied to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Eleonora Villa , Licia Verde , Sabino Matarrese

Relativistic cosmological perturbation analyses can be made based on several different fundamental gauge conditions. In the pressureless limit the variables in certain gauge conditions show the correct Newtonian behaviors. Considering the…

Astrophysics · Physics 2015-06-24 J. Hwang , H. Noh

We study the Newtonian cosmology taking into account the leading classical and quantum corrections of order $\mathcal{O}(G^{2})$ in the Newtonian potential. We first derive the modified Friedmann equations starting from the non-relativistic…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Rituparna Mandal , Sunandan Gangopadhyay , Amitabha Lahiri

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

We consider a new variant of cosmological perturbation theory that has been designed specifically to include non-linear density contrasts on scales 100 Mpc, while still allowing for linear fluctuations on larger scales. This theory is used…

General Relativity and Quantum Cosmology · Physics 2019-04-08 Christopher S. Gallagher , Timothy Clifton

We study the consequences of the $f(R/\Box)$ gravity models for the Solar system and the large scale structure of the universe. The spherically symmetric solutions can be used to obtain bounds on the constant and the linear parts of the…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Tomi S. Koivisto

Numerical simulations are a versatile tool providing insight into the complicated process of structure formation in cosmology. This process is mainly governed by gravity, which is the dominant force on large scales. To date, a century after…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-04 Julian Adamek , David Daverio , Ruth Durrer , Martin Kunz