A Test of the Cosmological Principle with Quasars

  title={A Test of the Cosmological Principle with Quasars},
  author={Nathan J. Secrest and Sebastian von Hausegger and Mohamed Rameez and Roya Mohayaee and Subir Kumar Sarkar and Jacques Colin},
  journal={The Astrophysical Journal Letters},
We study the large-scale anisotropy of the universe by measuring the dipole in the angular distribution of a flux-limited, all-sky sample of 1.36 million quasars observed by the Wide-field Infrared Survey Explorer (WISE). This sample is derived from the new CatWISE2020 catalog, which contains deep photometric measurements at 3.4 and 4.6 μm from the cryogenic, post-cryogenic, and reactivation phases of the WISE mission. While the direction of the dipole in the quasar sky is similar to that of… 
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