Let $X$ be a projective, equidimensional, singular scheme over an algebraically closed field. Then the existence of a geometric smoothing (i.e. a family of deformations of $X$ over a smooth base curve whose generic fibre is smooth) implies the existence of a formal smoothing as defined by Tziolas. In this paper we address the reverse question giving sufficient conditions on $X$ that guarantee the converse, i.e. formal smoothability implies geometric smoothability. This is useful in light of Tziolas' results giving criteria for the existence of formal smoothings. We also present a criterion to determine whether a formal deformation of a local complete intersection scheme is a formal smoothing by considering only a finite number of infinitesimal thickenings.

On formal schemes and smoothings

Nobile, Alessandro
2022

Abstract

Let $X$ be a projective, equidimensional, singular scheme over an algebraically closed field. Then the existence of a geometric smoothing (i.e. a family of deformations of $X$ over a smooth base curve whose generic fibre is smooth) implies the existence of a formal smoothing as defined by Tziolas. In this paper we address the reverse question giving sufficient conditions on $X$ that guarantee the converse, i.e. formal smoothability implies geometric smoothability. This is useful in light of Tziolas' results giving criteria for the existence of formal smoothings. We also present a criterion to determine whether a formal deformation of a local complete intersection scheme is a formal smoothing by considering only a finite number of infinitesimal thickenings.
30-mar-2022
Inglese
Fantechi, Barbara
SISSA
Trieste
File in questo prodotto:
File Dimensione Formato  
Tesi - Nobile.pdf

accesso aperto

Dimensione 723.01 kB
Formato Adobe PDF
723.01 kB Adobe PDF Visualizza/Apri

I documenti in UNITESI sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14242/166484
Il codice NBN di questa tesi è URN:NBN:IT:SISSA-166484