From inflation to late time acceleration with a decaying vacuum coupled
  to radiation or matter
  We consider General Relativity with matter and radiation, one of these fluids
being coupled to vacuum. We find that Universe dynamics starts by an inflation
phase if the coupled fluid has a negative energy density at early time. Then,
there is always a finite scale factor singularity but when vacuum and matter
are coupled and matter density behaves like a negative radiation density.
Moreover, the convergence to the LCDM model is clearly easier to reach when
vacuum is coupled to matter rather than to radiation. Two classes of theories
are studied to illustrate these results.
