inspiration and trepidation.

there was a seminar .. actually, a colloquium .. today, before lunch, but h. furstenburg spoke. it was the sort of talk in which one consistently asks oneself,

wow, really?
you can do that?

i've mentioned my idiosyncratic responses to good talks before, but this was really something.

so many disparate bits of mathematics .. just enough to be recognisable, but deep enough to cause wonder, even trepidation:

actions of topological groups on measure spaces,
measure theory and weak-* topologies,
affine group representations and irreducible ones (whatever those are)
harmonic functions and möbius transformations,
i.i.d. random variables and martingales,
hints at margulis-type rigidity theorems for appropriate types of boundary.

i felt like i saw the enormity of mathematics, and supposed that perhaps universalism did not die with poincaré, that it may still live on.

that troubled me. it wasn't until i ate a sandwich and drank a coffee that i felt somewhat like my old self.