A local version of the Fulton-Hansen theorem relating secant and tangential varieties
Withdrawn by the authors, the main theorem is incorrect
math.AG↗
arXiv subjects
J. Piontkowski
Publications and source records attributed to J. Piontkowski.
The Automorphism Group of Linear Sections of the Grassmannians G(1,N)
The Grassmannians of lines in projective N-space, G(1,N), are embedded by way of the Pl"ucker embedding in the projective space P(\bigwedge^2 C^{N+1}). Let H^l be a general l-codimensional linear subspace in this projective space. We examine the geometry of the linear sections G(1,N)\cap H^l by studying their automorphism groups and list those which are homogeneous or quasihomogeneous.
math.AG↗