Abstract
Following up a recent proposal BF for a cyclic model based on phantom
dark energy, we examine the content of the contracting universe (cu) and its
entropy $S_cu$. We find that beyond dark energy the universe contains on
average zero or at most a single photon which if present immediately after
turnaround has infinitesimally energy which subsequently blue shifts to produce
$e^+e^-$ pairs. These statements are independent of the equation of state
$= p/\rho$ of dark energy provided $< -1$. Thus $S_cu = 0$ and
if observations confirm $< -1$ the entropy problem is solved. We discuss
the absence of a theoretical lower bound on $= |+ 1|$, then
describe an anthropic fine tuning argument that renders unlikely extremely
small $\phi$. The present bound $0.1$ already implies a time
until turnaround of $(t_T - t_0) 100$ Gy.
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