English
Related papers

Related papers: Jeans analysis in energy-momentum-squared gravity

200 papers

A scalar-tensor theory of gravity is formulated in which $G$ and particle masses are allowed to vary. The theory yields a globally static cosmological model with no evolutionary timescales, no cosmological coincidences, and no flatness and…

General Physics · Physics 2015-10-01 Meir Shimon

Neutron stars (NSs) are excellent natural laboratories to constrain gravity on strong field regime and nuclear matter in extreme conditions. Motivated by the recent discovery of a compact object with $2.59^{+0.08}_{-0.09} M_\odot$ in the…

High Energy Astrophysical Phenomena · Physics 2020-12-07 Rafael C. Nunes , Jaziel G. Coelho , José C. N. de Araujo

(Abridged). We present numerical simulations of isothermal, MHD, supersonic turbulence, designed to test various hypotheses frequently assumed in star formation(SF) theories. We consider three simulations, each with a different combination…

Astrophysics of Galaxies · Physics 2015-06-17 Alejandro González-Samaniego , Enrique Vázquez-Semadeni , Ricardo F. González , Jongsoo Kim

We discuss the Mass -Radius diagram for static neutron star models obtained by the numerical solution of modified Tolman-Oppenheimer-Volkoff equations in $f(R)$ gravity where the Lagrangians $f(R)=R+\alpha R^2 (1+\gamma R)$ and…

General Relativity and Quantum Cosmology · Physics 2016-01-13 Salvatore Capozziello , Mariafelicia De Laurentis , Ruben Farinelli , Sergei D. Odintsov

The gravitational stability of a two-dimensional self-gravitating and differentially rotating gaseous disk in the context of post-Newtonian (hereafter PN) theory is studied. Using the perturbative method and applying the second iterated…

High Energy Astrophysical Phenomena · Physics 2018-09-25 Ali Kazemi , Mahmood Roshan , Elham Nazari

This thesis investigates compact astrophysical objects within modified theories of gravity, focusing on neutron stars and strange stars. The work studies their internal structure, equilibrium, and stability in gravitational frameworks based…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Sneha Pradhan

Large-scale cosmological galaxy formation simulations typically prevent gas in the interstellar medium (ISM) from cooling below $\approx 10^4$ K. This has been motivated by the inability to resolve the Jeans mass in molecular gas…

Astrophysics of Galaxies · Physics 2024-02-16 Sylvia Ploeckinger , Folkert S. J. Nobels , Matthieu Schaller , Joop Schaye

This study investigates the modeling of anisotropic magnetized static neutron stars within the framework of five-dimensional Einstein-Gauss-Bonnet (5D EGB) gravity. While Einstein's gravity has traditionally been employed to examine neutron…

General Relativity and Quantum Cosmology · Physics 2025-08-21 Mohammad Mazhari

This manuscript is based on an investigation of bouncing cosmology in a 4D Einstein Gauss-Bonnet gravity. Various bouncing models such as symmetric bounce, matter bounce, super bounce, and oscillatory bounce have been examined. Expressions…

General Relativity and Quantum Cosmology · Physics 2023-06-16 M. Zubair , Mushayydha Farooq

We present three numerical simulations of randomly driven, isothermal, non-magnetic, self-gravitating turbulence with different rms Mach numbers Ms and physical sizes L, but approximately the same value of the virial parameter, alpha approx…

We investigate cosmological signatures of the minimal theory of massive gravity (MTMG). To this aim, we simulate the normal branch of the MTMG by employing the \textsc{Ramses} \mbox{$N$-body} code and extending it with an effective…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 R. Hagala , A. De Felice , D. F. Mota , S. Mukohyama

In the framework of Einstein-scalar-Gauss-Bonnet (EsGB) gravity, we systematically study gravitational waves (GWs), first produced by remote compact astrophysical sources and then propagating through the flat homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2025-03-05 Jared Fier , Henry Han , Bowen Li , Kai Lin , Shinji Mukohyama , Anzhong Wang

Proper motions of collisionless pointlike objects in a spherically symmetric system, for example stars in a galaxy, can be used to test whether that system is in equilibrium, with no assumptions regarding isotropy. In particular, the fourth…

Astrophysics of Galaxies · Physics 2017-07-04 Jarah Evslin , Antonino Del Popolo

In this letter we compute stringent astrophysical and cosmological constraints on a recently proposed Eddington-inspired Born-Infeld theory of gravity. We find, using a generalized version of the Zel'dovich approximation, that in this…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-16 P. P. Avelino

In this paper, we introduce the post-Minkowskian approximation of Energy-Momentum-Squared Gravity (EMSG). This approximation is used to study the gravitational energy flux in the context of EMSG. As an application of our results, we…

General Relativity and Quantum Cosmology · Physics 2022-02-14 Elham Nazari , Mahmood Roshan , Ivan De Martino

In the homoeoidal expansion, a given ellipsoidally stratified density distribution, and its associated potential, are expanded in the (small) density flattening parameter $\eta$, and usually truncated at the linear order. The truncated…

Astrophysics of Galaxies · Physics 2023-12-13 Antonio Mancino , Luca Ciotti , Silvia Pellegrini , Federica Giannetti

Motivated by recent observational searches of sub-structure in starless molecular cloud cores, we investigate the evolution of density perturbations on scales smaller than the Jeans length embedded in contracting isothermal clouds, adopting…

Solar and Stellar Astrophysics · Physics 2017-12-20 C. Toci , D. Galli , A. Verdini , L. Del Zanna , S. Landi

The question of the existence of gravitational stress-energy in general relativity has exercised investigators in the field since the inception of the theory. Folklore has it that no adequate definition of a localized gravitational…

History and Philosophy of Physics · Physics 2019-11-26 Erik Curiel

We employ both the minimal gravity- and the minimal gauge mediations of supersymmetry breaking at the grand unified theory (GUT) scale in a single supergravity framework, assuming the gaugino masses are generated dominantly by the minimal…

High Energy Physics - Phenomenology · Physics 2015-06-02 Bumseok Kyae

In this work, we derive for the first time observational constraints on the extended Minimal Theory of Massive Gravity (eMTMG) framework in light of Planck-CMB data, geometrical measurements from Baryon Acoustic Oscillation (BAO), Type Ia…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-08 Antonio De Felice , Suresh Kumar , Shinji Mukohyama , Rafael C. Nunes
‹ Prev 1 4 5 6 7 8 10 Next ›