Estimation of mass and cosmological constant of nearby spiral galaxies using galaxy rotation curve

TL;DR

This study derives an expression for galaxy rotation velocities considering the cosmological constant and estimates the mass and $\\Lambda$ of 15 nearby spiral galaxies, revealing a negative $\\Lambda$ indicative of anti-de Sitter space influence.

Contribution

It introduces a method to estimate galaxy mass and local cosmological constant using rotation curves within Schwarzschild de-Sitter spacetime.

Findings

Galaxy masses range from 0.13 to 7.60 x 10^{40} kg.

The cosmological constant is negative, suggesting anti-de Sitter space effects.

Results highlight the significance of local $\\Lambda$ in galaxy dynamics.

Abstract

An expression for rotational velocity of a test particle around the central mass in the invariant plane is derived. For this, a line element of Schwarzschild de-Sitter space-time is used to study the effect of cosmological constant ($\Lambda$) on the motion of both massive and massless particles. Using rotation curve data of 15 nearby spiral and barred spiral galaxies, we estimated the mass and $\Lambda$ of the galaxy. The mass of the galaxies are found to lie in the range 0.13-7.60 $\times$ 10$^{40}$ kg. The cosmological constant ($\Lambda$) is found to be negative ($-$0.03 to $-$0.10 $\times$ 10$^{-40}$ km$^{-2}$), suggesting the importance of anti-de Sitter space in the local bubble. Possible explanation of the results will be discussed.