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