On Dark Matter As A Geometric Effect in the Galactic Halo

Abstract

We obtain more straightforwardly some features of dark matter distribution in the halos of galaxies by considering the spherically symmetric space-time, which satisfies the flat rotational curve condition, and the geometric equation of state resulting from the modified gravity theory. In order to measure the equation of state for dark matter in the galactic halo, we provide a general formalism taking into account the modified $f(X)$ gravity theories. Here, $f(X)$ is a general function of $X\in \{R,\mathcal{G},T\}$, where $R,\mathcal{G}$ and $T$ are the Ricci scalar, the Gauss-Bonnet scalar and the torsion scalar, respectively. These theories yield that the flat rotation curves appear as a consequence of the additional geometric structure accommodated by those of modified gravity theories. Constructing a geometric equation of state $w_{{}_X}\equiv p_{{}_X}/{\rho }_{{}_X}$ and inspiring by some values of the equation of state for the ordinary matter, we infer some properties of dark matter in galactic halos of galaxies.

arXiv comment11 pages, 2, tables, 2 figures; Matches published version in Astrophysics and Space Science

References in corpus (22)

• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• Halo Formation in Warm Dark Matter Models
• Dark Matter Self-interactions and Small Scale Structure
• The Connection between Galaxies and their Dark Matter Halos
• Dark Matter and Dark Radiation
• Low surface brightness galaxies rotation curves in the low energy limit of $R^n$ gravity : no need for dark matter?
• Fluid Dark Matter
• Spherically symmetric solutions in f(R)-gravity via Noether Symmetry Approach
• How the Self-Interacting Dark Matter Model Explains the Diverse Galactic Rotation Curves
• Dark matter as a geometric effect in f(R) gravity
• Galactic Halos of Fluid Dark Matter
• Scalar Field as Dark Matter in the Universe
• Spherical Scalar Field Halo in Galaxies
• Weak-Field Spherically Symmetric Solutions in $f(T)$ gravity
• Modelling galaxy halos using dark matter with pressure
• Galactic Rotation Dynamics in f(T) gravity
• Solar System Tests in Modified Teleparallel Gravity
• Dark matter and non-Newtonian gravity from General Relativity coupled to a fluid of strings
• Exact Spherically Symmetric Solutions in Modified Teleparallel gravity
• The Impact of Molecular Gas on Mass Models of Nearby Galaxies
• Exact spherically symmetric solutions in modified Gauss-Bonnet gravity from Noether symmetry approach
• Dynamics of a Dark Matter Field with a Quartic Self-Interaction Potential

Cited by in corpus (2)

• Galactic rotation curves of spiral galaxies and dark matter in f(R,T) gravity theory
• Friedmann's Universe Controlled by Gauss-Bonnet Modified Gravity