  A study is made of how active membrane proteins can modify the long
wavelength mechanics of fluid membranes. The activity of the proteins is
modelled as disturbing the protein surroundings through non-local force
distributions of which a force-dipole distribution is the simplest example. An
analytic expression describing how the activity modifies the force-balance
equation for the membrane surface is obtained in the form of a moment expansion
of the force distribution. This expression allows for further studies of the
consequences of the activity for non-planar membranes. In particular the active
contributions to mechanical properties such as tension and bending moments
become apparent. It is also explained how the activity can induce a
hydrodynamic attraction between the active proteins in the membrane.
