The physics of angular momentum transport from galactic scales (~10-100 pc)to much smaller radii is one of the oustanding problems in our understanding ofthe formation and evolution of super-massive black holes (BHs). Seeminglyunrelated observations have discovered that there is a lopsided stellar disk ofunknown origin orbiting the BH in M31, and possibly many other systems. We showthat these nominally independent puzzles are in fact closely related.Multi-scale simulations of gas inflow from galactic to BH scales show that whensufficient gas is driven towards a BH, gravitational instabilities form alopsided, eccentric disk that propagates inwards from larger radii. Thelopsided stellar disk exerts a strong torque on the remaining gas, drivinginflows that fuel the growth of the BH and produce quasar-level luminosities.The same disk can produce significant obscuration along many sightlines andthus may be the putative 'torus' invoked to explain obscured active galacticnuclei and the cosmic X-ray background. The stellar relic of this disk is longlived and retains the eccentric pattern. Simulations that yield quasar-levelaccretion rates produce relic stellar disks with kinematics, eccentricpatterns, precession rates, and surface density profiles in reasonableagreement with observations of M31. The observed properties of nuclear stellardisks can thus be used to constrain the formation history of super-massive BHs.
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