Astrophysics (index)about

Radio Source Counts

(Source Counts)
(using radio source population characteristics to determine curvature)

In Cosmology, Radio Source Counts (or just Source Counts) is a method of detecting the Curvature of space. In a flat, Euclidean space, a uniform distribution of Radio sources (the scale of interest being cosmological distances, i.e., Radio Galaxies), with the same distribution of Luminosities throughout, implies a certain pattern to the count of detectable sources at each luminosity:

log N = -1.5 log S

Divergence from this gives information about the geometry of the universe over time.