English
Related papers

Related papers: Singularities with respect to Mather-Jacobian disc…

200 papers

We investigate properties of potentially Du Bois singularities, that is, those that occur on the underlying space of a Du Bois pair. We show that a normal variety $X$ with potentially Du Bois singularities and Cartier canonical divisor…

Algebraic Geometry · Mathematics 2020-11-10 Patrick Graf , Sándor J Kovács

In this paper we give a new point of view for optimizing the definitions related to the study of singularities of normal varieties, introduced in [dFH09] and further studied in [Urb12a] and [Urb12b], in relation to the Minimal Model…

Algebraic Geometry · Mathematics 2012-11-28 Alberto Chiecchio , Stefano Urbinati

We survey determinantal singularities, their deformations, and their topology. This class of singularities generalizes the well studied case of complete intersections in several different aspects, but exhibits a plethora of new phenomena…

Algebraic Geometry · Mathematics 2021-06-10 Anne Frühbis-Krüger , Matthias Zach

In "Singularities on Normal Varieties", de Fernex and Hacon started the study of singularities on non-Q-Gorenstein varieties using pullbacks of Weil divisors. In "Log Terminal Singularities", the author of this paper and Urbinati introduce…

Algebraic Geometry · Mathematics 2013-09-25 Alberto Chiecchio

For a normal subvariety $V$ of ${\bf C}^n$ with a good ${\bf C}^*$-action we give a simple characterization for when it has only log canonical, log terminal or rational singularities. Moreover we are able to give formulas for the…

Algebraic Geometry · Mathematics 2007-05-23 Hubert Flenner , Mikhail Zaidenberg

Consider a normal complex analytic surface singularity. It is called Gorenstein if the canonical line bundle is holomorphically trivial in some punctured neighborhood of the singular point and is called numerically Gorenstein if this line…

Algebraic Geometry · Mathematics 2019-12-19 Patrick Popescu-Pampu

There are many generalizations of the McKay correspondence for higher dimensional Gorenstein quotient singularities and there are some applications to compute the topological invariants today. But some of the invariants are completely…

Algebraic Geometry · Mathematics 2007-05-23 Yukari Ito

The minimal log discrepancy is an invariant of singularities that plays an important role in the birational classification of algebraic varieties. Shokurov conjectured that the minimal log discrepancy can always be bounded from above in…

Algebraic Geometry · Mathematics 2025-11-24 Leandro Meier

In this paper we study singularities defined by the action of Frobenius in characteristic $p > 0$. We prove results analogous to inversion of adjunction along a center of log canonicity. For example, we show that if $X$ is a Gorenstein…

Algebraic Geometry · Mathematics 2010-01-18 Karl Schwede

We study deformations of certain crepant resolutions of isolated rational Gorenstein singularities. After a general discussion of the deformation theory, we specialize to dimension $3$ and consider examples which are good (log) resolutions…

Algebraic Geometry · Mathematics 2026-05-27 Robert Friedman , Radu Laza

We describe the generic singularity of a Schubert variety of type A on each irreducible component of its singular locus. This singularity is given either by a cone of rank one matrices, or a quadratic cone.

Algebraic Geometry · Mathematics 2007-05-23 Laurent Manivel

We continue the development of the study of the equisingularity of isolated singularities, in the determinantal case. This version of the paper includes a substantial amount of new material (76% larger). The new material introduces the idea…

Complex Variables · Mathematics 2016-01-05 Terence Gaffney , Antoni Rangachev

In this paper, we prove that klt singularities are invariant under deformations if the generic fiber is $\mathbb{Q}$-Gorenstein. We also obtain a similar result for slc singularities. These are generalizations of results of Esnault-Viehweg…

Algebraic Geometry · Mathematics 2022-07-05 Kenta Sato , Shunsuke Takagi

We study a useful numerical invariant of normal surface singularities, introduced recently by T. Kawachi. Using this invariant, we give a quick proof of the (well-known) fact that all log-canonical surface singularities are either elliptic…

alg-geom · Mathematics 2008-02-03 Vladimir Masek

We prove that a Cohen-Macaulay normal variety $X$ has Du Bois singularities if and only if $\pi_*\omega_{X'}(G) \simeq \omega_X$ for a log resolution $\pi: X' \to X$, where $G$ is the reduced exceptional divisor of $\pi$. Many basic…

Algebraic Geometry · Mathematics 2010-05-25 Sándor J. Kovács , Karl E. Schwede , Karen E. Smith

In 2009, de Fernex and Hacon proposed a generalization of the notion of the singularities to normal varieties that are not Q-Gorenstein. Based on their work, we generalize Kleiman's transversality theorem to subvarieties with log terminal…

Algebraic Geometry · Mathematics 2011-11-21 Chih-Chi Chou

We show that there exists a positive real number $\delta>0$ such that for any normal quasi-projective $\mathbb{Q}$-Gorenstein $3$-fold $X$, if $X$ has worse than canonical singularities, that is, the minimal log discrepancy of $X$ is less…

Algebraic Geometry · Mathematics 2021-12-24 Chen Jiang

In this paper we investigate the singularities of Lagrangian mean curvature flows in $\mathbf{C}^m$ by means of smooth singularity models. Type I singularities can only occur at certain times determined by invariants in the cohomology of…

Differential Geometry · Mathematics 2015-05-11 Andrew A. Cooper

We give an example of a non $\Q$-Gorenstein variety which is canonical but not klt, and whose canonical divisor has an irrational valuation. We also give an example of an irrational jumping number and we prove that there are no accumulation…

Algebraic Geometry · Mathematics 2016-12-16 Stefano Urbinati

The philosophy of the article is that the desingularization invariant together with natural geometric information can be used to compute local normal forms of singularities. The idea is used in two related problems: (1) We give a proof of…

Algebraic Geometry · Mathematics 2011-08-22 Edward Bierstone , Pierre D. Milman