The Calculations of Gravity Fields and Rotation Curves of Whirlpool Galaxies and Dark Material

TL;DR

This paper demonstrates that the flat rotation curves of whirlpool galaxies can be explained using Newtonian gravity with thin disc mass distributions, eliminating the need for dark matter hypotheses.

Contribution

It provides a numerical analysis showing that proper thin disc mass distributions account for galaxy rotation curves without dark matter.

Findings

Flat rotation curves explained by Newtonian gravity and thin disc models

Dark material outside the disc is unnecessary for flat rotation curves

Non-luminous baryon material suffices to explain observations

Abstract

The gravity fields and rotation curves of whirlpool galaxies with thin disc distribution of material are calculated numerically. It is proved that the gravity field of mass thin disc distribution is greatly different from that of spherically symmetrical distribution. As long as the Newtonian theory of gravity is used strictly, by the proper mass distributions of thin discs, the flat rotation curves of whirlpool galaxies can be explained well. The rotating curve of the Milky Galaxy is obtained which coincides with practical observation. In this way, it is unnecessary for us to suppose the existence of additional dark material in the illuminant discs of whirlpool galaxy again. Meanwhile, in the space outside the illuminant disc, the quantity of dark material needed to maintain the flatness of rotation curves is greatly decreased. By considering the observation fact that the quantity of non-luminous baryon material is 3~10 times more than luminous material, we can explain the flatness of rotation curves of whirlpool galaxies well without the hypotheses of non-baryon dark material. So it is unnecessary for us to suppose that non-baryon dark material is about 5 times more than baryon material in a single whirlpool galaxy, no mater whether non-baryon dark material exits or not.