Mathematical Research Letters

Volume 30 (2023)

Number 5

Deformations of log Calabi–Yau pairs can be obstructed

Pages: 1357 – 1374

DOI: https://dx.doi.org/10.4310/MRL.2023.v30.n5.a3

Authors

Simon Felten (Department of Mathematics, Columbia University, New York, N.Y., U.S.A.)

Andrea Petracci (Dipartimento di Matematica, Università di Bologna, Bologna, Italy)

Sharon Robins (Department of Mathematics, Simon Fraser University, Burnaby, British Columbia, Canada)

Abstract

We exhibit examples of pairs $(X,D)$ where $X$ is a smooth projective variety and $D$ is an anticanonical reduced simple normal crossing divisor such that the deformations of $(X,D)$ are obstructed. These examples are constructed via toric geometry.

Received 13 September 2021

Received revised 10 January 2022

Accepted 19 January 2022

Published 14 May 2024