Why a Windy Torus?
  Mass ejection in the form of winds or jets appears to be as fundamental to
quasar activity as accretion, and can be directly observed in many objects with
broadened and blue-shifted UV absorption features. A convincing argument for
radiation pressure driving this ionized outflow can be made within the dust
sublimation radius. Beyond, radiation pressure is even more important, as high
energy photons from the central engine can now push on dust grains. This
physics underlies the dusty-wind model for the putative obscuring torus.
Specifically, the dusty wind in our model is first launched from the outer
accretion disk as a magneto-centrifugal wind and then accelerated and shaped by
radiation pressure from the central continuum. Such a wind can plausibly
account for both the necessary obscuring medium to explain the ratio of
broad-to-narrow-line objects and the mid-infrared emission commonly seen in
quasar spectral energy distributions. A convincing demonstration that
large-scale, organized magnetic fields are present in radio-quiet active
galactic nuclei is now required to bolster the case for this paradigm.
