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Responsabili:

Federica Galluzzi  ed  Elena Martinengo
 

Nel calendario si indicano i seminari di geometria algebrica e altre attività di interesse, organizzate dall'Università e dal Politecnico di Torino.

Evento
Titolo: Lefschetz defect in families
Quando: 19/12/2024 - 10:30
Dove: Palazzo Campana - TORINO
Aula: Aula Lagrange
Relatore: Matteo Verni
Afferenza: Université Paris-Saclay
Locandina: Locandina

Descrizione:

Abstract:

The Lefschetz defect of a smooth projective variety roughly measures the difference between the Picard number of the variety and that of its
prime divisors. This invariant was introduced by Casagrande in 2012 and it turned out to be very useful in her work on the classification of Fano
fourfolds.
In this talk, we present a new cohomological characterization of the Lefschetz defect. This allows us to deduce stability properties for it; in particular,
its invariance under smooth deformations of Fano manifolds.

Sede
Sede: Palazzo Campana
Indirizzo: Via Carlo Alberto n.10
CAP: 10123
Città: TORINO