  The radiative transport equation accurately describes light transport in
participating media such as biological tissues, though analytic solutions are
known only for simple geometries. We present a pseudospectral technique to
efficiently compute numerical solutions to the time-dependent transport
equation in arbitrary three-dimensional heterogeneous media with anisotropic
scattering. Our GPU-accelerated implementation of the technique is validated by
comparison with a Monte-Carlo simulation, demonstrating excellent agreement.
