  One of the most important and poorly-understood issues in structure formation
is the role of outflows driven by active galactic nuclei (AGN). Using
large-scale cosmological simulations, we compute the impact of such outflows on
the small-scale distribution of the cosmic microwave background (CMB). Like
gravitationally-heated structures, AGN outflows induce CMB distortions both
through thermal motions and peculiar velocities, by processes known as the
thermal and kinetic Sunyaev-Zel'dovich (SZ) effects, respectively. For AGN
outflows the thermal SZ effect is dominant, doubling the angular power spectrum
on arcminute scales. But the most distinct imprint of AGN feedback is a
substantial increase in the thermal SZ distortions around elliptical galaxies,
post-starburst ellipticals, and quasars, which is linearly proportional to the
outflow energy. While point source subtraction is difficult for quasars, we
show that by appropriately stacking microwave measurements around early-type
galaxies, the new generation of small-scale microwave telescopes will be able
to directly measure AGN feedback at the level important for current theoretical
models.
