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Related papers: A note on graded hypersurface singularities

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Assume that there exists a hypersurface singularity which cannot be resolved by iterated monoidal transformations in positive characteristic. We show that in the set of defining functions of hypersurface singularities which cannot be…

Algebraic Geometry · Mathematics 2010-06-21 Tohsuke Urabe

Thanks to the recent work of Bhupal, Stipsicz, Szabo, and the author, one has a complete list of resolution graphs of weighted homogeneous complex surface singularities admitting a rational homology disk ("QHD") smoothing, i.e., one with…

Algebraic Geometry · Mathematics 2015-03-17 Jonathan Wahl

In this paper the singular hypersurfaces in $\mathbb{C}\mathrm{P}^4$ of degree $d$ with an isolated singularity are studied. If the singularity is of type $A_{2k+1}$, under the condition $d<(k+5)/2$, a classification of such hypersurfaces…

Geometric Topology · Mathematics 2007-05-23 Yang Su

We study singularities of surfaces which are given by Kenmotsu-type formula with prescribed unbounded mean curvature.

Differential Geometry · Mathematics 2019-04-10 Luciana F. Martins , Kentaro Saji , Keisuke Teramoto

One considers quasihomogeneous isolated singularities of hypersurfaces in arbitrary dimensions through the lenses of three apparently quite apart themes: syzygies, singularity invariants, and foliations. In the first of these, one adds to…

Commutative Algebra · Mathematics 2025-09-23 Hamid Hassanzadeh , Abbas Nasrollah Nejad , Aron Simis

We enumerate complex algebraic hypersurfaces in $P^n$, of a given (high) degree with one singular point of a given singularity type. Our approach is to compute the (co)homology classes of the corresponding equi-singular strata in the…

Algebraic Geometry · Mathematics 2014-02-26 Dmitry Kerner

We introduce and study the vanishing homology of singular projective hypersurfaces. We prove its concentration in two levels in case of 1-dimensional singular locus $\Sigma$, and moreover determine the ranks of the nontrivial homology…

Algebraic Geometry · Mathematics 2017-09-11 Dirk Siersma , Mihai Tibar

In this paper we give a necessary combinatorial condition for a negative--definite plumbing tree to be suitable for rational blow--down, or to be the graph of a complex surface singularity which admits a rational homology disk smoothing.…

Geometric Topology · Mathematics 2008-03-13 Andras I. Stipsicz , Zoltan Szabo , Jonathan Wahl

Let $X$ be surface with isolated singularities in the complex projective space $P^3$ and let denote $Y$ the smooth part of $X$. In this note we discuss some aspects of the topology of such quasi-projective surfaces $Y$: the fundamental…

Algebraic Geometry · Mathematics 2017-08-30 Alexandru Dimca

We study singular del Pezzo surfaces that are quasi-smooth and well-formed weighted hypersurfaces. We give an algorithm how to classify all of them.

Algebraic Geometry · Mathematics 2025-09-03 Erik Paemurru

The {\it two-fold singularity} has played a significant role in our understanding of uniqueness and stability in piecewise smooth dynamical systems. When a vector field is discontinuous at some hypersurface, it can become tangent to that…

Dynamical Systems · Mathematics 2015-06-04 Mike R. Jeffrey

We give a survey on some aspects of the topological investigation of isolated singularities of complex hypersurfaces by means of Picard-Lefschetz theory. We focus on the concept of distinguished bases of vanishing cycles and the concept of…

Algebraic Geometry · Mathematics 2019-05-30 Wolfgang Ebeling

This is a short note on the relation between the graded stable derived categories of 14 exceptional unimodal singularities and the derived category of K3 surfaces obtained as compactifications of the Milnor fibers. As a corollary, we obtain…

Algebraic Geometry · Mathematics 2012-03-06 Masanori Kobayashi , Makiko Mase , Kazushi Ueda

We smooth the singularities of a strictly hyperbolized smooth cube manifold.

Differential Geometry · Mathematics 2014-12-01 Pedro Ontaneda

Fixed a point O on a non-singular surface S and a complete mO-primary ideal I in its local ring, the curves on the surface X obtained by blowing-up I are studied in terms of the base points of I. Criteria for the principality of these…

Algebraic Geometry · Mathematics 2007-05-23 Jesus Fernandez-Sanchez

We construct examples of flat surfaces in $\mathbb{H}^3$ which are graphs over a two-punctured horosphere and classify complete embedded flat surfaces in $\mathbb{H}^3$ with only one end and at most two isolated singularities.

Differential Geometry · Mathematics 2009-05-15 Armando V. Corro , Antonio Martinez , Francisco Milan

In this paper we present some properties for projective hypersurfaces, smooth and singular, to be criteria for identification. To make the decision with these criteria, we have included procedures written in Singular language.

Algebraic Geometry · Mathematics 2014-01-09 Gabriel Sticlaru

A sequence of monoidal transformations is defined, in terms of invariants, for a singular hypersurface embedded in a smooth scheme of positive characteristic. Some examples are added to illustrate the improvement of singularities by this…

Algebraic Geometry · Mathematics 2011-07-25 Angélica Benito , Orlando Villamayor

We study singularities obtained by the contraction of the maximal divisor in compact (non kaehlerian) surfaces which contain global spherical shells. These singularities are of genus 1 or 2, may be Q-Gorenstein, numerically Gorenstein or…

Complex Variables · Mathematics 2008-01-07 Georges Dloussky

We describe singularities of height functions on singular surfaces in $\mathbb{R}^3$ parameterized by smooth map-germs $\mathcal{A}$-equivalent to one of $S_k$, $B_k$, $C_k$ and $F_4$ singularities in terms of extended geometric language…

Differential Geometry · Mathematics 2024-08-27 Toshizumi Fukui , Masaru Hasegawa