Eckardt loci on hypersurfaces
CoskunIzzet
PrendergastArtie
2015
We compute the dimensions and cohomology classes of the loci on a general hypersurface where the second fundamental
form has rank at most r. We also determine the number of hypersurfaces in a general pencil in P
n, with n =
`q+1
2
´
,
that contain a point where the second fundamental form has rank n − 1 − q. These results generalize many classical formulae.