Non-elementary Fano conic bundles

By Anonymous (not verified), 23 January, 2026
Aula
Aula C
Speaker
Eleonora Romano
Afferenza
Università di Torino
Descrizione

Starting from a Fano variety, namely a smooth, complex, projective variety

whose anticanonical divisor is ample, we consider a particular kind of fiber

type contraction on it, a "Fano conic bundle" whose fibers are isomorphic to

conics in the two-dimensional projective space.

First we recall some geometric properties about such contractions.

Then we focus on the relative cone of the conic bundle, that is the real

vectorial subspace of the cone of curves in which there are all classes of

numerical equivalence of curves that are contracted by the conic bundle.

In particular, we consider the contractions in which the dimension of the

relative cone is greater than one, called " non-elementary" .

We will discuss a new result about non-elementary Fano conic bundles, that

gives us a bound for the dimension of the relative cone, and allows us to

deduce other information about the geometry of our varieties.

Data