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Responsabili:

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

# Two invariants related to two conjectures due to Nagata

## Data:

22/09/2022 - 09:30

Aula Buzano

## Speaker:

Michel Waldschmidt

## Categoria:

Seminari di Algebra e Geometria Algebrica

Sorbonne,Paris

## Descrizione:

Abstract : Seshadri’s constant is related to a conjecture due to Nagata. Another conjecture, al-
so due to Nagata and solved by Bombieri in 1970, is related with algebraic values of
meromorphic functions. The main argument of Bombieri’s proof leads to a Schwarz
Lemma in several variables, the proof of which gives rise to another invariant associa-
ted with symbolic powers of the ideal of functions vanishing on a finite set of points.
This invariant is an asymptotic measure of the least degree of a polynomial in seve-
ral variables with given order of vanishing on a finite set of points. Recent works on
the resurgence of ideals of points and the containment problem compare powers and
symbolic powers of ideals.