  The stress tensor for the quantized electromagnetic field is calculated in
the region between a pair of dispersive, dielectric half-spaces. This
generalizes the stress tensor for the Casimir energy to the case where the
boundaries have finite reflectivity. We also include the effects of finite
temperature. This allows us to discuss the circumstances under which the weak
energy condition and the null energy condition can be violated in the presence
of finite reflectivity and finite temperature.
