  We discuss the construction of the analog of an S-matrix for space-times that
begin with a Big-Bang and asymptote to an FRW universe with nonnegative
cosmological constant. When the cosmological constant is positive there are
many such S-matrices, related mathematically by gauge transformations and
physically by an analog of the principle of black hole complementarity. In the
limit of vanishing $\Lambda$ these become (approximate) Poincare transforms of
each other. Considerations of the initial state require a quantum treatment of
space-time, and some preliminary steps towards constructing such a theory are
proposed. In this context we propose a model for the earliest semiclassical
state of the universe, which suggests a solution for the horizon problem
different from that provided by inflation.
