David Treumann
<br>
Title: Hypersurface skeleta
<br>
Abstract: Rene Thom's proof of the Lefschetz hyperplane theorem
shows that a
smooth affine variety X of complex dimension d can be made to
deformation retract onto a cell complex of real dimension d.  I
will
describe an explicit such "skeleton" when X is an affine
hypersurface.
 The skeleton has another natural realization as a singular
Legendrian
subset of S^d x T^{d+1} with a natural contact structure.
Because of
this, the skeleton carries a sheaf of triangulated categories,
the
"Kashiwara-Schapira sheaf."  I will explain these things and
their
relevance in the homological mirror symmetry program.  This
talk is
based on joint work with Ruddat, Sibilla and Zaslow, as well as
on
earlier joint work with Fang, Liu and Zaslow.