  A comprehensive microscopic dynamical theory is presented for the description
of quantum fluids as they transform into glasses. The theory is based on a
quantum extension of mode-coupling theory. Novel effects are predicted, such as
reentrant behavior of dynamical relaxation times. These predictions are
supported by path integral ring polymer molecular dynamics simulations. The
simulations provide detailed insight into the factors that govern slow dynamics
in glassy quantum fluids. Connection to other recent work on both quantum
glasses as well as quantum optimization problems is presented.
