Eric Swenson

On the domain of discontinuity of a hyperbolic CAT(0) isometry

We examine the domain of discontinuity a hyperbolic CAT(0) isometry in the
boundary of the CAT(0) space.We also give a canonical decomposition of the    
boundary of a CAT(0) space as the spherical join   
of a sphere and a CAT(1) space having no spherical join factors.