We have three geometry talks, followed by dinner on Tuesday, September 14th.

Getting things started, at 11:00, our own Michael Dobbins, is speaking on:

Title: Realizability of the antiprism

Abstract: In 1985 Mark Broadie gave sufficient conditions for realizing the antiprism of a polytope. Whether the antiprism of every polytope can be realized is still listed as an open problem in Branko Grunbaum’s book Convex Polytopes. In this talk, I will give necessary and sufficient conditions, and provide a counter example.

We reconvene at our usual time, 3:30, in Wachman 617, for talks by two visiting speakers.

Kasra Rafi is speaking on:

Title: Fellow traveling properties of Teichmüller geodesics.

Abstract: We review some results describing the behavior of a Teichmüller
geodesic and draw some conclusions that seem useful. In particular,
we show that a Teichmüler geodesic segment has the fellow traveling
property if its end points are in the thick part of Teichmüller space.
We also provide counter examples for this when the end points are not in
the thick part.

Ara Basmajian will speak on:

Title: The orthogonal spectrum revisited

Abstract: This talk will be an exposition of some results on the orthogonal spectrum (nowadays called the orthospectrum).