Holography in (2+1)-dimensional cosmological models

The cosmic halographic principle suggested by Fischler and Susskind has bee n examined in (2 + 1)-dimensional cosmological models. Analogously to the ( 3 + 1)-dimensional counterpart, the holographic principle is satisfied in a ll flat and open universes. For (2 + 1)-dimensional closed universes the ho lographic principle cannot be realized in general. The principle cannot be maintained, neither introducing negative pressure matter nor matter with hi ghly unconventional equation of state. (C) 1999 Published by Elsevier Scien ce B.V. All rights reserved.