The angular scale of homogeneity in the Local Universe with the SDSS
  blue galaxies
  We probe the angular scale of homogeneity in the local Universe using blue
galaxies from the SDSS survey as a cosmological tracer. Through the scaled
counts in spherical caps, $ \mathcal{N}(<\theta) $, and the fractal correlation
dimension, $\mathcal{D}_{2}(\theta)$, we find an angular scale of transition to
homogeneity for this sample of $\theta_{\text{H}} = 22.19^{\circ} \pm
1.02^{\circ}$. A comparison of this measurement with another obtained using a
different cosmic tracer at a similar redshift range ($z < 0.06$), namely, the
HI extragalactic sources from the ALFALFA catalogue, confirms that both results
are in excellent agreement (taking into account the corresponding bias
correction). We also perform tests to asses the robustness of our results. For
instance, we test if the size of the surveyed area is large enough to identify
the transition scale we search for, and also we investigate a reduced sample of
blue galaxies, obtaining in both cases a similar angular scale for the
transition to homogeneity. Our results, besides confirming the existence of an
angular scale of transition to homogeneity in different cosmic tracers present
in the local Universe, show that the observed angular scale $\theta_{\text{H}}$
agrees well with what is expected in the $\Lambda$CDM scenario. Although we can
not prove spatial homogeneity within the approach followed, our results provide
one more evidence of it, strengthening the validity of the Cosmological
Principle.
