Concordance between observations and simulations in the evolution of the
  mass relation between supermassive black holes and their host galaxies
  We carry out a comparative analysis of the relation between the mass of
supermassive black holes (BHs) and the stellar mass of their host galaxies at
$0.2<z<1.7$ using well-matched observations and multiple state-of-the-art
simulations (e.g., Massive Black II, Horizon-AGN, Illustris, TNG and a
semi-analytic model). The observed sample consists of 646 uniformly-selected
SDSS quasars ($0.2 < z < 0.8$) and 32 broad-line AGNs ($1.2<z<1.7$) with
imaging from Hyper Suprime-Cam (HSC) for the former and Hubble Space Telescope
(HST) for the latter. We first add realistic observational uncertainties to the
simulation data and then construct a simulated sample in the same manner as the
observations. Over the full redshift range, our analysis demonstrates that all
simulations predict a level of intrinsic scatter of the scaling relations
comparable to the observations which appear to agree with the dispersion of the
local relation. Regarding the mean relation, Horizon-AGN and TNG are in closest
agreement with the observations at low and high redshift ($z\sim$ 0.2 and 1.5,
respectively) while the other simulations show subtle differences within the
uncertainties. For insight into the physics involved, the scatter of the
scaling relation, seen in the SAM, is reduced by a factor of two and closer to
the observations after adopting a new feedback model which considers the
geometry of the AGN outflow. The consistency in the dispersion with redshift in
our analysis supports the importance of both quasar and radio mode feedback
prescriptions in the simulations. Finally, we highlight the importance of
increasing the sensitivity, e.g., JWST, thereby pushing to lower masses and
minimizing biases due to selection effects.
