Since January of this year, I have been busy with mathematics after a long absence. A collaborator visited to complete some old work. Around the time he left, I found a new paper dealing in a comprehensive way some things that I did not understand back in the nineties. Reading half of that paper took two months and it started me thinking about some related problems. It may not lead to any new work but would clarify some stuff for me in an area I worked for a long time. So, posts will be infrequent for a few more months I think. Meanwhile I have been posting on Facebook.