Interpretation of cosmological information on radio sources

The question as to whether or not any cosmological information can be obtained from radio astronomy is discussed. The areas discussed in this paper are: 1) The discovery and interpretation of the microwave background radiation. 2) The identification of powerful radio sources and the discovery that many of them have large redshifts. If it can be proved that the large redshifts mean that the objects are at great distances, then these radio sources can be used as follows: (a) One can attempt to obtain a Hubble relation for the optical objects which are identified with radio galaxies; (b) One can look for a relation between the angular diameters of the radio sources and the redshifts of the optically identified objects and one can also look at relations between the angular diameter and the radio flux; (c) One can construct log N - log S curves and carry out luminosity volume tests. (Auth.)