Does the quasar dipole break LambdaCDM?
Cosmology seminar by Arefe Abghari, UBC
Tuesday 11:00 Toronto (GMT-4)
Recording available
Recording
Abstract
Arefe Abghari tests whether the reported excess in the quasar number-density dipole challenges the Cosmological Principle. If large-scale homogeneity and isotropy hold, the motion responsible for the cosmic microwave background dipole should also predict the dipole in distant-source counts. The analysis examines quasar selection and dipole-estimation systematics. Higher multipoles in the quasar density map, plausibly caused by survey and selection effects, can explain the apparent discrepancy. The talk argues that these effects need careful control before interpreting the measurements as evidence against the standard cosmological model.
Topics
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