Quasars’ orientations may be determined by universe’s structure

Ars Technica : Quasars, which are black holes at the center of galaxies, produce more light from their accretion disks than is produced by the rest of the stars in their parent galaxies combined. A survey of 93 extremely distant quasars by Damien Hutsemékers of the University of Liège in Belgium and his colleagues has revealed a possible connection between quasars and the universe’s large-scale structure. The light from the quasars they looked at was produced when the universe was only one-third as old as it is now. The researchers noticed that some of the quasars’ axes of rotation appeared to be aligned with each other despite being separated by billions of light-years. To determine just how closely aligned they were, Hutsemékers’s team measured the polarization of the light from the quasars, which has previously been shown to correlate to the orientation of a quasar’s accretion disk. Of the 93 quasars, 19 were highly polarized and had broad radiation spectra, a sign that the quasar is highly inclined with respect to Earth. By comparing those quasars with a map of the filamentary structure of the universe, the researchers show that the quasars are all aligned parallel to the filaments in which they are located. The researchers believe there is a less than 1% chance that this is a random distribution.