Unknown selection effect simulates redshift periodicity in quasar number counts from Sloan Digital Sky Survey

TL;DR

The paper demonstrates that observed redshift periodicities in Sloan Digital Sky Survey quasars are likely due to selection effects rather than intrinsic quantization, emphasizing the importance of accounting for observational biases.

Contribution

It reveals that apparent redshift periodicities are caused by selection effects, not intrinsic quasar properties, challenging previous interpretations of redshift quantization.

Findings

Redshift periodicities match patterns in data quality flags.

Selection effects can mimic intrinsic redshift signals.

No evidence for intrinsic redshift quantization in quasars.

Abstract

Discrete Fourier analysis on the quasar number count, as a function of redshift, $z$, calculated from the Sloan Digital Sky Survey DR6 release appears to indicate that quasars have preferred periodic redshifts with redshift intervals of 0.258, 0.312, 0.44, 0.63, and 1.1. However the same periods are found in the mean of the $zConf$ parameter used to flag the reliability of the spectroscopic measurements. It follows that these redshift periods must result from some selection effect, as yet undetermined. It does not signal any intrinsic (quantized) redshifts in the quasars.