I’m going to abuse this here organ of mine ((phrasing?!?!)) to show off a thing I did yesterday.

My chum the inimitable David Cushing has started a postgrad pure maths seminar at Newcastle. Because there are only a few pure postgrads here, he asked me to give a talk about the stuff I was looking at for the PhD I gave up on last year.

The title of the talk was “Computability of Bass-Serre structures in the Grzegorczyk hierarchy”. It gave an outline of everything needed to show that the fundamental group of a graph of groups is computable in a level of the Grzegorczyk hierarchy at most one higher than its constituent parts, and what that means.

The slides, a recording of the talk, and a link to my presentation template are in a post on my mathem-o-blog: Talk: Computability of Bass-Serre structures in the Grzegorczyk hierarchy

“Started”? I think you might mean “resurrected” ;-) see

here or here.

In any case, good to see some form of postgrad seminar is running once again. (And regards to David, BTW.)

The PGF is still going, but pure talks don’t get a good reception there. We decided we needed somewhere we could talk about proper maths without the statisticians being rude.

Oops – I misread in my haste.