Cosmic Homogeneity Demonstrated with Luminous Red Galaxies


Hogg DW, Eisenstein DJ, Blanton MR, Bahcall NA, Brinkmann J, Gunn JE, Schneider DP. Cosmic Homogeneity Demonstrated with Luminous Red Galaxies. The Astrophysical Journal. 2005;624 :54-58.

Date Published:

May 1, 2005


We test the homogeneity of the universe at z~0.3 with the luminous redgalaxy (LRG) spectroscopic sample of the Sloan Digital Sky Survey.First, the mean number N(R) of LRGs within completely surveyedLRG-centered spheres of comoving radius R is shown to be proportional toR3 at radii greater than R~70h-1Mpc. The test hasthe virtue that it does not rely on the assumption that the LRG samplehas a finite mean density; its results show, however, that there is sucha mean density. Second, the survey sky area is divided into 10 disjointsolid angular regions, and the fractional rms density variations of theLRG sample in the redshift range 0.27h-3Mpc3) regions is found