Numerical Models of Accretion Flows Around Black Holes

James Stone, Princeton University Observatory

Observations of black hole candidates at the center of the Milky Way
and other galaxies indicate they radiate far less energy than expected
based on the inferred rate of accretion of surrounding plasma.  The
resolution of this discrepancy may lie in the dynamics of the accreting
plasma.  It is now possible to compute the structure and evolution of
accretion flows around compact objects such as black holes from first
principles, by solving the equations of radiation magnetohydrodynamics
using numerical methods.  I will summarize the results of a series of
numerical experiments which investigate the properties of
time-dependent flows in 2D and 3D, and which are providing new insights
into the physics of accretion flows.