A big bounce, slow-roll inflation and dark energy from conformal gravity
  We examine the cosmological sector of a gauge theory of gravity based on the
SO(4,2) conformal group of Minkowski space. We allow for conventional matter
coupled to the spacetime metric as well as matter coupled to the field that
gauges special conformal transformations. An effective cosmological constant is
generated dynamically via solution of the equations of motion, and this allows
us to recover the late time acceleration of the universe. Furthermore,
gravitational fields sourced by ordinary cosmological matter (i.e. dust and
radiation) are significantly weakened in the very early universe, which has the
effect of replacing the big bang with a big bounce. Finally, we find that this
bounce is followed by a period of nearly-exponential slow roll inflation that
can last long enough to explain the large scale homogeneity of the cosmic
microwave background.
