  Microphase separation of membrane components is thought to play an important
role in many physiological processes, from cell signaling to endocytosis and
cellular trafficking. Here, we study how variations in the membrane composition
can be driven by fluctuating forces. We show that the membrane steady state is
not only controlled by the strength of the forces and how they couple to the
membrane, but also by their dynamics: In a simple class of models this is
captured by a single a correlation time. We conclude that the coupling of
membrane composition to normal mechanical forces, such as might be exerted by
polymerizing cytoskeleton filaments, could play an important role in
controlling the steady state of a cell membrane that exhibits transient
microphase separation on lengthscales in the 10-100 nm regime.
