DAVID: It is April's fools day, I think:-http://arxiv.org/pdf/1503.08130v1.pdf-Thank you so much for this invaluable reference. I was in despair after Professor Miyagawa's MIT had rejected my application for a research grant (see "Origin of Language", 5 April at 14.15), but hope springs eternal... I shall now apply to the Harish-Chandra Research Institute. And I have a new theory to develop: our universe is made of a renewable substance called zogipantopyrussurypotnapigoz, which means it can NEVER END. They can't possibly turn me down, can they?