  We present a theory for pore dynamics of osmotically stressed vesicles. When
a liposome with an internal concentration of solute is placed inside a
solute-depleted medium, an osmotic flow of solvent through the lipid bilayer
leads to swelling of vesicle and to increase in membrane surface tension. This
can result in membrane rupture and opening of thermal pores. Depending on the
internal concentration of solute and the size of the vesicle, pores can close
rapidly or be long-lived. We find that the life span of the long-lived pores
scales non-trivially with the size of the liposome. Closure of the long-lived
pore is followed by a rapid flicker-like opening and closing of short-lived
pores. Our model is consistent with the observation of long-lived pores in red
blood cell ghosts.
