3 papers
math.AG2004
On singular varieties having an extremal secant line
Marie-Amélie Bertin
We correct a mistake in an earlier paper and give a complete classification of singular varieties having an extremal secant line.
math.AG2002
On trisecant lines to White surfaces
Marie-Amelie Bertin
In this work we show that the only White surface in the projective 5-space having an excess of trisecant lines is the polygonal surface constructed by C. Segre. The proof follows t…
math.AG2000
On the regularity of varieties having an extremal secant line
Marie-Amélie Bertin
The Castelnuovo-Mumford regularity of varieties of degree r and dimension n in the r-dimensional projective space that have an extremal secant line, is at least d-r+n+1. We classif…