5:00 pm, 26 agosto: Apparent boundaries of projective varieties

Fix a smooth projective variety in projective space and project it to a linear subspace of the same dimension. The ramification divisor of this projection is classically known as the "apparent boundary". How does the apparent boundary move when we move the center of projection? I will discuss the geometry arising from this natural question. I will explain why the situation is most interesting for varieties of minimal degree, and how it is related to limit linear series for vector bundles.