The planck length as a cosmological constraint

Abstract

Any attempt at unification of gravity with quantum physics inevitably leads to the Planck length, usually interpreted as defining the distance scale at which quantum corrections to general relativity are expected to become important. Here the author arrives at a scalelength of the same magnitude from the cosmological requirement that gravitating vacuum or zero-point energy does not overdominate the dynamics of the Universe. Other cosmological considerations are again seen to imply such a constraining lower scalelength.