Recruiting quasars in cosmology

There is a discrepancy in the two accurate measurements of the Hubble constant under the assumption of the standard cosmological model. Quasars, if standardized, can be used as candles in cosmology to determine the constant. This requires the calibration of the known radius-luminosity relation which is a relation between the absolute luminosity of the quasar and distance of  its broad line region (BLR) from the central black hole. Broad Emission Lines are the most characteristic feature in the quasar’s spectra, known since 60 years but we need a theoretical model for its localization. The most successful non-ad-hoc physically-motivated model during the last decade which consistently explains the formation of broad emission lines in the spectra of quasars and provides the information on the location of BLR is the failed radiatively accelerated dusty outflow (FRADO). The model currently available in the 2.5D advanced version which I developed has taken very progressive concrete steps toward the ultimate goal. I will explain the story from scratch up to date.

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Room D or Zoom (Link)

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