English
Related papers

Related papers: On the classification of singular cubic threefolds

200 papers

In this work, we show that for a certain class of threefolds in positive characteristics, rational-chain-connectivity is equivalent to supersingularity. The same result is known for K3 surfaces with elliptic fibrations. And there are…

Algebraic Geometry · Mathematics 2019-09-11 Santai Qu

We study surfaces of constant positive Gauss curvature in Euclidean 3-space via the harmonicity of the Gauss map. Using the loop group representation, we solve the regular and the singular geometric Cauchy problems for these surfaces, and…

Differential Geometry · Mathematics 2016-03-02 David Brander

We classify simple parametrisations of complex curve singularities. Simple means that all neighbouring singularities fall in finitely many equivalence classes. We take the neighbouring singularities to be the ones occurring in the versal…

Algebraic Geometry · Mathematics 2018-12-12 Jan Stevens

Fourteen kinds of triangle singularities with modality one in Arnold's classification list are discussed. We consider which kinds of combinations of rational double points can appear on small deformation fibers of the singularities. We show…

alg-geom · Mathematics 2008-02-03 Tohsuke Urabe

We solve the problem on flat extensions of a generic surface with boundary in Euclidean 3-space, relating it to the singularity theory of the envelope generated by the boundary. We give related results on Legendre surfaces with boundaries…

Differential Geometry · Mathematics 2010-01-08 Goo Ishikawa

We define an invariant, which we call surface-complexity, of closed 3-manifolds by means of Dehn surfaces. The surface-complexity of a manifold is a natural number measuring how much the manifold is complicated. We prove that it fulfils…

Geometric Topology · Mathematics 2019-01-30 Gennaro Amendola

In this paper we consider cubic 4-folds containing a plane whose discriminant curve is a reduced nodal plane sextic. In particular, we describe the singular points of such cubic 4-folds and we give an estimate of the rank of the free…

Algebraic Geometry · Mathematics 2011-09-13 Paolo Stellari

The elliptic curves on a surface of general type constitute an obstruction for the cotangent sheaf to be ample. In this paper, we give the classification of the configurations of the elliptic curves on the Fano surface of a smooth cubic…

Algebraic Geometry · Mathematics 2010-01-27 Xavier Roulleau

We classify stably simple reducible curve singularities in complex spaces of any dimension. This extends the same classification of of irreducible curve singularities obtained by V.I.Arnold. The proof is essentially based on the method of…

Algebraic Geometry · Mathematics 2012-03-06 Pavel A. Kolgushkin , Rustam R. Sadykov

Line congruences are $2$-dimensional families of lines in $3$-space. The singularities that appear in generic line congruences are folds, cusps and swallowtails. In this paper we give a geometric description of these singularities. The main…

Differential Geometry · Mathematics 2021-10-26 Marcos Craizer , Ronaldo Alves Garcia

The dual complex can be associated to any resolution of singularities whose exceptional set is a divisor with simple normal crossings. It generalizes to higher dimensions the notion of the dual graph of a resolution of surface singularity.…

Algebraic Geometry · Mathematics 2007-05-23 D. A. Stepanov

We discuss the bi-Lipschitz geometry of an isolated singular point of a complex surface which particular emphasis on when it is metrically conical.

Algebraic Geometry · Mathematics 2009-03-07 Lev Birbrair , Alexandre Fernandes , Walter D. Neumann

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

This work presents a range of triangulated characterizations for important classes of singularities such as derived splinters, rational singularities, and Du Bois singularities. An invariant called 'level' in a triangulated category can be…

Algebraic Geometry · Mathematics 2025-03-05 Pat Lank , Sridhar Venkatesh

We classify all wormhole singularities, i.e. cyclic quotient surface singularities admitting at least two extremal P-resolutions, thereby solving an open problem posed by Urz\'ua. Our approach introduces a new combinatorial framework based…

Algebraic Geometry · Mathematics 2025-12-10 Jaime Negrete

This paper is a detailed study of a class of isolated Gorenstein threefold singularities, called hyperconifolds, that are finite quotients of the conifold. First, it is shown that hyperconifold singularities arise naturally in limits of…

Algebraic Geometry · Mathematics 2013-09-27 Rhys Davies

In this survey on combinatorial properties of triangulated manifolds we discuss various lower bounds on the number of vertices of simplicial and combinatorial manifolds. Moreover, we give a list of all known examples of vertex-minimal…

Combinatorics · Mathematics 2007-05-23 Frank H. Lutz

In this paper we show that a simplicial complex can be determined uniquely up to isomorphism by its barycentric subdivision or comparability graph. At the end, it is summarized several algebraic, combinatorial and topological invariants of…

Commutative Algebra · Mathematics 2013-03-15 Rashid Zaare-Nahandi

We consider links of complex isolated hypersurface singularities in $\mathbb{C}^{n+1}$ and study differentiable maps defined by restricting holomorphic functions to the links. We give an explicit example in which such a restriction gives a…

Geometric Topology · Mathematics 2024-02-06 Osamu Saeki , Shuntaro Sakurai

We study linearizability of actions of finite groups on singular cubic threefolds, using cohomological tools, intermediate Jacobians, Burnside invariants, and the equivariant Minimal Model Program.

Algebraic Geometry · Mathematics 2025-01-07 Ivan Cheltsov , Yuri Tschinkel , Zhijia Zhang