English

Testing homogeneity in the Sloan Digital Sky Survey Data Release Twelve with Shannon entropy

Cosmology and Nongalactic Astrophysics 2015-10-21 v2

Abstract

We analyze a set of volume limited samples from SDSS DR12 to quantify the degree of inhomogeneity at different length scales using Shannon entropy. We find that the galaxy distributions exhibit a higher degree of inhomogeneity as compared to a Poisson point process at all length scales. Our analysis indicates that signatures of inhomogeneities in the galaxy distributions persist at least upto a length scale of 120h1Mpc120 \, h^{-1}\, {\rm Mpc}. The galaxy distributions appear to be homogeneous on a scale of 140h1Mpc140 \, h^{-1}\, {\rm Mpc} and beyond. Analyzing a set of mock galaxy samples from a semi analytic galaxy catalogue from the Millennium simulation we find a scale of transition to homogeneity at 100h1Mpc\sim 100 \, h^{-1}\, {\rm Mpc}.

Keywords

Cite

@article{arxiv.1507.03124,
  title  = {Testing homogeneity in the Sloan Digital Sky Survey Data Release Twelve with Shannon entropy},
  author = {Biswajit Pandey and Suman Sarkar},
  journal= {arXiv preprint arXiv:1507.03124},
  year   = {2015}
}

Comments

Added 2 new figures and expanded some discussion, Accepted for publication in MNRAS