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Related papers: Flat rotation curves using scalar-tensor theories

200 papers

We consider a modification of General Relativity motivated by the treatment of anisotropies in Continuum Mechanics. The Newtonian limit of the theory is formulated and applied to galactic rotation curves. By assuming that the additional…

General Relativity and Quantum Cosmology · Physics 2018-06-25 Christian G. Boehmer , Nicola Tamanini , Matthew Wright

We model the NFW potential to determine if, and under what conditions, the NFW halo appears consistent with the observed velocity fields of low surface brightness (LSB) galaxies. We present mock DensePak IFU velocity fields and rotation…

Astrophysics · Physics 2011-02-11 Rachel Kuzio de Naray , Stacy S. McGaugh , J. Christopher Mihos

The logarithmic superfluid theory of physical vacuum predicts that gravity is an induced phenomenon, which has a multiple-scale structure. At astronomical scales, as the distance from a gravitating center increases, gravitational potential…

General Relativity and Quantum Cosmology · Physics 2022-01-13 Konstantin G. Zloshchastiev

We present first results of a program to study the dynamics of undisturbed bulgeless, low surface density disk galaxies in order to probe the underlying structure of dark matter halos. High resolution H-alpha rotation curves are combined…

Astrophysics · Physics 2007-05-23 J. J. Dalcanton , R. A. Bernstein

The dark matter constraint imposed by the recent WMAP experiment on gravitational theories is analyzed. Using the non-linearity of the vacuum Einstein's equations, it is shown that when the slow motion condition is applied to the geodesic…

Astrophysics · Physics 2007-05-23 M. D. Maia , A. J. S. Capistrano , D. Mulller

The velocity distribution function (VDF) of the hypothetical Weakly Interacting Massive Particles (WIMPs), currently the most favored candidate for the Dark Matter (DM) in the Galaxy, is determined directly from the circular speed…

Astrophysics of Galaxies · Physics 2013-05-01 Pijushpani Bhattacharjee , Soumini Chaudhury , Susmita Kundu , Subhabrata Majumdar

The spacetime satisfying the flat curve condition for galaxies is shown to be the zero mass limit of the dilaton blackhole with an exponential potential. We derive the geodesic equations and by studying rotational curves and light…

General Relativity and Quantum Cosmology · Physics 2019-03-06 Yen-Kheng Lim

While the standard and most popular explanation for the flatness of galaxy rotation curves is dark matter, one cannot at this stage rule out an explanation based on a modified law of gravitation, which agrees with Newtonian gravitation on…

Astrophysics of Galaxies · Physics 2012-06-18 Priti Mishra , Tejinder P. Singh

For the spherical symmetric case, all quantities describing the relaxed dark matter halo can be expressed as functions of the gravitational potential $\Phi$. Decomposing the radial velocity dispersion $\sigma_r$ with respect to $\Phi$ at…

Astrophysics · Physics 2009-11-07 J. P. Muecket , M. Hoeft

The parameters of an axisymmetric model for the gravitational potential of the Galaxy have been refined. The basic curve of the Galaxy's rotation in a distance interval of $R:0-190$ kpc was constructed using the velocities of masers,…

Astrophysics of Galaxies · Physics 2026-01-14 V. V. Bobylev , A. T. Bajkova , A. A. Smirnov

I propose a modification of the spherical infall model for the evolution of density fluctuations with initially Gaussian probability distribution and scale-free power spectra. I introduce a generalized form of the initial density…

Astrophysics · Physics 2007-05-23 Ewa L. Lokas

Feng & Gallo (2011) developed a numerical method of deriving rotation curves from the density distribution and, in particular, the inverse problem while considering just a self-gravitating disc and the thin disc approximation. Our first aim…

Astrophysics of Galaxies · Physics 2020-03-16 Gonzalo Fernandez-Torija Daza , Martin Lopez-Corredoira

We propose a new formula to explain circular velocity profiles of spiral galaxies obtained from the Starobinsky model in Palatini formalism. It is based on the assumption that the gravity can be described by two conformally related metrics:…

General Relativity and Quantum Cosmology · Physics 2018-04-13 Ciprian A. Sporea , Andrzej Borowiec , Aneta Wojnar

We derive inner dark matter halo density profile slopes for a sample of 200 dwarf galaxies by inverting rotation curves obtained from high-quality, long-slit optical spectra. Using simulations to assess the impact of long-slit observing and…

Astrophysics · Physics 2007-05-23 K. Spekkens , R. Giovanelli

Spiral galaxies are considered as static, spherically symmetric Dark Matter Configurations (DMC)in which non-zero rest-mass particles (NZRPs) move along appropriate trajectories. Using general relativity (GR), we show that a mass of dark…

Astrophysics · Physics 2007-05-23 P. S. Negi

We present a new empirical model for galaxy rotation curves that introduces a velocity correction term {\omega}, derived from observed stellar motion and anchored to Keplerian baselines. Unlike parametric halo models or modified gravity…

Astrophysics of Galaxies · Physics 2026-01-05 David C. Flynn , Jim Cannaliato

We investigate the mass profile of LambdaCDM halos using a suite of numerical simulations spanning five decades in halo mass, from dwarf galaxies to rich galaxy clusters. Our analysis confirms the proposal of Navarro, Frenk & White (NFW)…

A theory is proposed which allows explaining the observed flat galaxy rotation curves, without needing to invoke dark matter. Whereas other theories have been proposed in the past which realize the same, the present theory rests on basic…

General Physics · Physics 2015-05-13 Rudi Van Nieuwenhove

Two incorrect arguments against MOND in elliptical galaxies could be that the equivalent circular velocity curves tend to become flat at much larger accelerations than in spiral galaxies, and that the Newtonian dark matter halos are more…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Tom Richtler , Benoit Famaey , Gianfranco Gentile , Ylva Schuberth

I report recent results of numerical simulations designed to study the inner structure of Cold Dark Matter (CDM) halos. This work confirms the proposal of Navarro, Frenk & White (NFW) that the shape of LambdaCDM halo mass profiles differs…

Astrophysics · Physics 2007-05-23 Julio F. Navarro