THE FORMATION OF GIANT LOW SURFACE BRIGHTNESS GALAXIES

We demonstrate that the initial structure of galaxies can be strongly affected by their large-scale environments. In particular, rare (approximately 3-sigma) massive galaxies in voids will have normal bulges, but unevolved, extended disks; we propose that the low surface brightness objects Malin I and Malin II are prototypes of this class of object. Our model predicts that searches for more examples of "crouching giants" should be fruitful, but that such galaxies do not provide a substantial fraction of mass in the universe. The identification of dwarf galaxies is relatively unaffected by their environment.