Morphology of the Local Volume
  To study the global morphology of the galaxy distribution in our local
neighbourhood we calculate the Minkowski functionals for a sequence of volume
limited samples within a sphere of 8 Mpc centred on our galaxy. The well known
strong clustering of the galaxies and the dominance of voids and coherent
structures on larger scales is clearly visible in the Minkowski functionals.
The morphology of the galaxy distribution changes with the limiting absolute
magnitude. The samples, encompassing the more luminous galaxies, show emptier
voids and more pronounced coherent structures. Indeed there is a prominent peak
in the luminosity function of isolated galaxies for MB approx. -14, which at
least partly explains these morphological changes. We compare with halo samples
from a LambdaCDM simulation. Special care was taken to reproduce the observed
local neighbourhood as well as the observed luminosity function in these mock
samples. All in all the mock samples render the global morphology of the galaxy
distribution quite well. However the detailed morphological analysis reveals
that real galaxies cluster stronger, the observed voids are emptier and the
structures are more pronounced compared to the mock samples from the LambdaCDM
simulation.
