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Related papers: Flat rotational curves without dark matter

200 papers

After explaining the motivation for this article, I briefly recapitulate the methods used to determine, somewhat coarsely, the rotation curves of our Milky Way Galaxy and other spiral galaxies, especially in their outer parts, and the…

Astrophysics · Physics 2008-04-25 Dilip G. Banhatti

We computed flat rotation curves from scalar-tensor theories in their weak field limit. Our model, by construction, fits a flat rotation profile for velocities of stars. As a result, the form of the scalar field potential and DM…

Astrophysics · Physics 2008-11-26 Jorge L. Cervantes-Cota , M. A. Rodriguez-Meza , Dario Nunez

By solving analytically the various types of Lane-Emden equations with rotation, we have discovered two new coupled fundamental properties of rotating, self-gravitating, gaseous disks in equilibrium: Isothermal disks must, on average,…

Astrophysics of Galaxies · Physics 2016-05-31 Dimitris M. Christodoulou , Demosthenes Kazanas

The existence of the flat rotation curves of galaxies is still perplexing. The dark matter paradigm was proposed long ago to solve this conundrum; however, this proposal is still under debate. In this paper, we search for universal…

Astrophysics of Galaxies · Physics 2022-10-25 G. Pascoli

The recent paper by Lee and Lee (2004) may strongly leave the impression that astronomers have established that the rotation curves of spiral galaxies are flat. We show that the old paradigm of Flat Rotation Curves lacks, today, any…

Astrophysics · Physics 2008-11-26 P. Salucci , G. Gentile

We use the concept of the spiral rotation curves universality to investigate the luminous and dark matter properties of the dwarf disc galaxies in the local volume (size $\sim11$ Mpc). Our sample includes 36 objects with rotation curves…

Astrophysics of Galaxies · Physics 2017-01-09 Ekaterina V. Karukes , Paolo Salucci

A new method is developed which permits the reconstruction of the surface-density distribution in the galactic disk of finite radius from an arbitrary smooth distribution of the angular velocity via two simple quadratures. The existence of…

Astrophysics · Physics 2009-11-07 N. R. Sibgatullin , A. A. Garcia , V. S. Manko

We review the topic of rotation curves of spiral galaxies emphasizing the standard interpretation as evidence for the existence of dark matter halos. Galaxies other than spirals and late-type dwarfs may also possess great amounts of dark…

Astrophysics · Physics 2007-05-23 Eduardo Battaner , Estrella Florido

The most spiral galaxies have a flat rotational velocity curve, according to the different observational techniques used in several wavelengths domain. In this work, we show that non-linear terms are able to balance the dispersive effect of…

Astrophysics of Galaxies · Physics 2021-12-03 Miroslava Vukcevic , Vladimir Zekovic , Marko Radeta

We derive a formula for the velocity distribution of an axially symmetric galaxy where the mass density is corrected using the mass formula from special relativity. We take some reasonable test mass densities and numerically compute the…

General Relativity and Quantum Cosmology · Physics 2023-02-21 Jaroslaw S. Jaracz

We investigate the possibility to explain theoretically the galaxy rotation curves by a gravitational potential in total absence of dark matter. To this aim an analytic fourth-order theory of gravity, nonminimally coupled with a massive…

General Relativity and Quantum Cosmology · Physics 2015-06-15 A. Stabile , S. Capozziello

The information contained in galactic rotation curves is examined under a minimal set of assumptions. If emission occurs from stable circular geodesic orbits of a static spherically symmetric field, with information propagated to us along…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Kayll Lake

Dark matter is estimated to make up ~84% of all normal/baryonic matter, but cannot be directly imaged. Despite the fact that dark matter cannot be directly observed yet, its influence on the motion of stars and gas in spiral galaxies have…

Physics Education · Physics 2023-08-10 A. N. Villano , Kitty C. Harris , Judit Bergfalk , Raphael Hatami , Francis Vititoe , Julia Johnston

We review the most recent evidence for the amazing properties of the density distribution of dark matter around spiral galaxies. Their rotation curves, coadded according to the galaxy luminosity, conform to an universal profile which can be…

Astrophysics · Physics 2007-05-23 P. Salucci , A. Borriello

Recently, it has been suggested that the phenomenology of flat rotation curves observed at large radii in the equatorial plane of disk galaxies can be explained as a manifestation of General Relativity instead of the effect of Dark Matter…

Astrophysics of Galaxies · Physics 2022-09-21 Luca Ciotti

The free electron model with Boltzmann statistics for spherical low-density plasmas is developed further with asymptotic relations obtaining the density of electrons, mass densities, and the potentials of such plasmas. Solutions are…

Astrophysics of Galaxies · Physics 2024-06-28 Y. Ben-Aryeh

The model of galactic halo as a system of the collisionless small neutral particles from the standpoint of kinetic theory is considered. For the equilibrium system with the use of Maxwell-Boltzmann distribution we obtained results which…

General Relativity and Quantum Cosmology · Physics 2011-11-03 Valentin D. Gladush

Most fully developed galaxies have a vivid spiral structure, but the formation and evolution of the spiral structure are still an enigma in astrophysics. In this paper, according to the standard Newtonian gravitational theory and some…

General Physics · Physics 2009-05-16 Ying-Qiu Gu

The rotation curves of 20 spiral galaxies are examined in the light of a toy model (Soares 1992) which has as the main feature the assignment of a high M/L ratio (=30; Ho=50 km/s/Mpc) to the visible matter. The observed rotation of all…

Astrophysics · Physics 2009-09-25 D. S. L. Soares

We present high-accuracy rotation curves, which show a steep nuclear rise and high-velocity central rotation, followed by a broad maximum in the disk and flat part. We use the rotation curves to directly calculate the radial distribution of…

Astrophysics · Physics 2007-05-23 Yoshiaki Sofue