Abstract
For disk galaxies the fourth power of the circular velocity v4c of stars around the core of the galaxy is proportional to the luminosity L, v4c ∝ L (Tully-Fisher law). Since L is proportional to the mass M of the galaxy, it follows that v4c ∝ M. Newtonian mechanics, however, yields v2c = GM/r for a circular motion. In order to rectify this big difference, astronomers assume the existence of dark matter. We derive the equation of motion of a star moving in the central field of a galaxy and show that, for a circular motion, it yields a term of the form v4c ∝ GMc/τ, where G is Newton's gravitational constant, c is the speed of light, and τ is the Hubble time. This puts in doubt the existence of halo dark matter for galaxies.
Original language | English |
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Pages (from-to) | 1397-1404 |
Number of pages | 8 |
Journal | International Journal of Theoretical Physics |
Volume | 39 |
Issue number | 5 |
DOIs | |
State | Published - 1 Jan 2000 |
ASJC Scopus subject areas
- General Mathematics
- Physics and Astronomy (miscellaneous)