Is the cause of inflation unknown? Is it possible that it might have in part at least been caused by radiation pressure as a result of matter annihilating anti-matter at extremely high densities? Does the theory of quintessence mainly try to say that inflation and dark energy are linked in some way? And that D.E. is a continuation of inflation? If so I have wondered if this was being proposed as a possibility myself, but I didn't realize it was being called Q.