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Related papers: Dynamics of Dwarf Galaxies in Scalar-Tensor-Vector…

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Scalar-tensor theories are among the most promising alternatives to general relativity that have been developed to account for some long standing issues in our understanding of gravity. Some of these theories predict the existence of a…

High Energy Astrophysical Phenomena · Physics 2021-01-06 J. Soldateschi , N. Bucciantini , L. Del Zanna

The aim of our investigation is to derive a particular theory among the class of scalar-tensor(ST) theories of gravity, and then to test it by studying kinematics and dynamics of S-stars around supermassive black hole (BH) at Galactic…

In this paper we constrain the sizes of hypothetical new weak forces by making use the data coming from the precession of Planets. We consider the weak field approximation of Scalar-Tensor Fourth Order Gravity (STFOG), which include several…

General Relativity and Quantum Cosmology · Physics 2022-07-20 Antonio Capolupo , Gaetano Lambiase , Antonio Tedesco

We investigate scalar-tensor theories, motivated by dark energy models, in the strong gravity regime around the black hole at the centre of our galaxy. In such theories general relativity is modified since the scalar field couples to…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-24 David Benisty , Anne-Christine Davis

We study the effects of massive scalar-tensor theories on the internal properties, crystallization, and cooling process of white dwarf stars that might potentially solve observational tensions. We show that these modified gravity theories…

General Relativity and Quantum Cosmology · Physics 2024-08-29 Sofía Vidal , Aneta Wojnar , Laur Järv , Daniela Doneva

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

The Advanced LIGO and Virgo collaborations recently detected a gravitational wave event, GW230529\_181500, during the fourth observing run, which is most plausibly attributed to the merger of a neutron star and a black hole. This…

General Relativity and Quantum Cosmology · Physics 2025-10-23 Baoxiang Wang , Tao Yang

We use time-resolved spectra from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) to examine the distribution of radial velocity (RV) variations in 249 stars identified as members of the Sagittarius (Sgr) dwarf…

We construct axisymmetric mass models for dwarf spheroidal (dSph) galaxies in the Milky Way to obtain plausible limits on the non-spherical structure of their dark halos. This is motivated by the fact that the observed luminous parts of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Kohei Hayashi , Masashi Chiba

We have found that the high velocity dispersions of dwarf spheroidal galaxies (dSphs) can be well explained by Milky Way (MW) tidal shocks, which reproduce precisely the gravitational acceleration previously attributed to dark matter (DM).…

Astrophysics of Galaxies · Physics 2019-09-24 F. Hammer , Y. B. Yang , J. L. Wang , F. Arenou , C. Babusiaux , M. Puech , H. Flores

We build a spherical halo model for galaxies using a general scalar-tensor theory of gravity in its Newtonian limit. The scalar field is described by a time-independent Klein-Gordon equation with a source that is coupled to the standard…

Astrophysics of Galaxies · Physics 2009-03-24 Jorge L. Cervantes-Cota , Mario A. Rodriguez-Meza , Dario Nunez

We forecast parameter uncertainties on the mass profile of a typical Milky Way dwarf spheroidal (dSph) galaxy using the spherical Jeans Equation and Fisher matrix formalism. We show that radial velocity measurements for 1000 individual…

Astrophysics of Galaxies · Physics 2021-12-13 Juan Guerra , Marla Geha , Louis E. Strigari

We derive the distribution of the phantom dark matter in the eight classical dwarf galaxies surrounding the Milky Way, under the assumption that modified Newtonian dynamics (MOND) is the correct theory of gravity. According to their…

Astrophysics of Galaxies · Physics 2020-10-02 Alistair O. Hodson , Antonaldo Diaferio , Luisa Ostorero

Using collisionless N-body simulations of dwarf galaxies orbiting the Milky Way (MW) we construct realistic models of dwarf spheroidal (dSph) galaxies of the Local Group. The dwarfs are initially composed of stellar disks embedded in dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Klaudia Kowalczyk , Ewa L. Lokas , Stelios Kazantzidis , Lucio Mayer

We obtain a high-dimensional Schwarzschild black hole solution in the scalar-tensor-vector gravity (STVG), and then analyze the influence of parameter $\alpha$ associated with a deviation of the STVG theory from General Relativity on event…

General Relativity and Quantum Cosmology · Physics 2021-07-05 Xin-Chang Cai , Yan-Gang Miao

Scalar Tensor Vector Gravity(STVG) is one of a modified gravity theory developed by John Moffat(2005). MOG is abbreviated name for this theory.This theory is added a massive vector field to Brans-Dicke theory. It can explain a galactic…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-21 Takayuki Suzuki

Theories with varying gravitational constant $G$ have been studied since long time ago. Among them, the most promising candidates as alternatives of the standard General Relativity are known as scalar-tensor theories. They provide…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Diego F. Torres

We present a new analysis of the relative detectability of dark matter annihilation in the Milky Way's eight classical dwarf spheroidal satellite galaxies. Ours is similar to previous analyses in that we use Markov-Chain Monte Carlo…

High Energy Astrophysical Phenomena · Physics 2011-07-05 M. G. Walker , C. Combet , J. A. Hinton , D. Maurin , M. I. Wilkinson

We study the prospects for the Large Synoptic Survey Telescope (LSST) to find new dwarf spheroidal galaxies in the Milky Way. Adopting models of Milky-Way halo substructure and phenomenological prescriptions connecting subhalos and…

In order to examine the gravitational waves emitted from the neutron stars in the tensor-vector-scalar (TeVeS) theory, we derive the perturbation equations for relativistic stars, where for simplicity we omit the perturbations of vector…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Hajime Sotani