Anisotropy in the Hubble constant as modeled by density gradients
  The all-sky maps of the observed variation of the Hubble constant can be
reproduced from a theoretical point of view by introducing an intergalactic
plasma with a variable number density of electrons. The observed averaged value
and variance of the Hubble constant are reproduced by adopting a rim model, an
auto-gravitating model, and a Voronoi diagrams model as the backbone for an
auto-gravitating medium. We also analyze an astronomer's model based on the 3D
spatial distribution of galaxies as given by the 2MASS Redshift Survey and an
auto-gravitating Lane--Emden ($n=5$) profile of the electrons. The simulation
which involves the Voronoi diagrams is done in a cubic box with sides of 100
Mpc. The simulation which involves the 2MASS covers the range of redshift
smaller than 0.05.
