相关论文: Can Born Infeld Gravity Explain Galaxy Rotation Cu…
Conformal geometry is considered within a general relativistic framework. An invariant distant for proper time is defined and a parallel displacement is applied in the distorted space-time, modifying Einstein's equation appropriately. A…
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:…
It is common to attribute a flat rotation curve to our Galaxy. However Galazutdinov et al. (2015) in a recent paper have obtained a Keplerian rotation curve for interstellar clouds in outer parts of the Galaxy. They have calculated the…
In this work, we investigate the possibility that the galaxy rotation curves can be explained in the framework of modified gravity models that introduce a Yukawa term in the gravitational potential. We include dark matter and assume that…
The description of gravity in the form of an embedding theory is based on the hypothesis that our space-time is a four-dimensional surface in a flat ten-dimensional space. The choice of standard Einstein-Hilbert action leads in this case to…
The connection between dark matter and giant black holes in the galactic nuclei is investigated. The joint evolution of dark and luminous matter in averaged self-consistent gravitational potential is considered. It is shown that the…
In this work, we submit the explanation of spectra of the rotary curves of galaxies on the basis of a vector theory of gravitation without regard to the dark matter hypothesis. We study the approximation of rotary curves in case of existing…
The phenomenology of MOND (flat rotation curves of galaxies, baryonic Tully-Fisher relation, etc.) is a basic set of phenomena relevant to galaxy dynamics and dark matter distribution at galaxy scales. Still unexplained today, it enjoys a…
The missing of a Keplerian fall-off in the observed galaxy rotation curves represents classical evidence for the existence of dark matter on galactic scales. There has been some recent activity concerning the potential of modelling galactic…
It is shown that Born-Infeld gravity --a high energy deformation of Einstein gravity-- removes the singularities of a cosmic string. The respective vacuum solution results to be free of conical singularity and closed timelike curves. The…
Although the cusp-core controversy for dwarf galaxies is seen as a problem, I argue that the cored central profiles can be explained by flattened cusps because they suffer from conflicting measurements and poor statistics and because there…
Owing to the existence of an invariant length at the Planck scale, Einstein special relativity breaks down at that scale. A possible solution to this problem is arguably to replace the Poincar\'e invariant Einstein special relativity by a…
The propagation of plane electromagnetic waves in the gravitational field inside a rotating cloud of dark matter is analyzed. Formulas for the deflection and absorption of light, and the rotation of the polarization plane are obtained in…
A review is given of a priori predictions made for the dynamics of rotating galaxies. One theory - MOND - has had many predictions corroborated by subsequent observations. While it is sometimes possible to offer post hoc explanations for…
In this paper we study consistent solutions of spherically symmetric space in metric f(R) gravity theory. Here we inversely obtain a generic action from metric solutions that describe flat rotation curves in spiral galaxies without dark…
We investigate the possibility that the galactic dark matter exists in an scenario where the phantom field is responsible for the dark energy. We obtain the statically and spherically approximate solution for this kind of the galaxy system…
According to Mach's principle inertia has its reason in the presence of all masses in the universe. Despite there is a lot of sympathy for this plausible idea, only a few quantitative frameworks have been proposed to test it. In this paper…
Galactic rotation curves exhibit diverse behavior in the inner regions, while obeying an organizing principle, i.e., they can be approximately described by a radial acceleration relation or the Modified Newtonian Dynamics phenomenology. We…
Rotation curves of dark-matter-dominated galaxies measure the mass profiles of galactic halos and thereby test theories of their cosmological origin. While attention has focused lately on the possible discrepancy at small galactocentric…
Multi-fractional theories with integer-order derivatives are models of gravitational and matter fields living in spacetimes with variable Hausdorff and spectral dimension, originally proposed as descriptions of geometries arising in quantum…