The Ultimate Fate of Life in an Accelerating Universe

The ultimate fate of life in a universe with accelerated expansion is considered. Previous work showed that life cannot go on indefinitely in a universe dominated by a cosmological constant. In this paper we consider instead other models of acceleration (including quintessence and Cardassian expansion). We find that it is possible in these cosmologies for life to persist indefinitely. As an example we study potentials of the form $V \propto \phi^n$andfindtherequirement$n < -2$.