Absence of a periodic component in the quasar z distribution

The presence of a periodic component in the quasar distribution over redshift z is investigated. The periodicity is analysed for the coordinate ln(1 + z ) and for the geodesic cosmological distance using the SDSS and 2dF catalogs (∼85 000 quasars). Four different criteria and the Fourier transform method were used to search for periodicity. The analysis shows an absence of a periodic component in the quasar redshift distribution at any significant confidence level.