English
Related papers

Related papers: Non-embeddable 1-convex manifolds

200 papers

We prove the existence of resolution of singularities for arbitrary (not necessarily reduced or irreducible) excellent two-dimensional schemes, via permissible blow-ups. The resolution is canonical, and functorial with respect to…

Algebraic Geometry · Mathematics 2013-02-19 Vincent Cossart , Uwe Jannsen , Shuji Saito

Let N be a closed irreducible 3-manifold and assume N is not a graph manifold. We improve for all but finitely many S^1-bundles M over N the adjunction inequality for the minimal complexity of embedded surfaces. This allows us to completely…

Geometric Topology · Mathematics 2018-12-24 Stefan Friedl , Stefano Vidussi

It is proved that any smooth manifold $\mathcal M$ of dimension $m$ admits a smooth polynomially convex embedding into $\mathbb C^n$ when $n\geq \lfloor 5m/4\rfloor$. Further, such embeddings are dense in the space of smooth maps from…

Complex Variables · Mathematics 2025-04-03 Purvi Gupta , Rasul Shafikov

In this paper we give the first example of a surface bundle over a surface with at least three fiberings. In fact, for each $n \ge 3$ we construct $4$-manifolds $E$ admitting at least $n$ distinct fiberings $p_i: E \to \Sigma_{g_i}$ as a…

Geometric Topology · Mathematics 2021-09-15 Nick Salter

In this paper we develop the theory of finite-type invariants for homologically nontrivial 3-manifolds. We construct an infinite-dimensional affine space with a hypersurface in it corresponding to manifolds with Morse singularities.…

q-alg · Mathematics 2008-02-03 Nadya Shirokova

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

All varieties, extremal contractions, singularities are divided on exceptional and non-exceptional ones. Roughly speaking, there are the infinite families of non-exceptional varieties, extremal contractions or singularities and only the…

Algebraic Geometry · Mathematics 2015-06-26 S. A. Kudryavtsev

Let $(X,o)$ be a germ of a 3-dimensional terminal singularity of index $m\geq 2$. If $(X,o)$ has type cAx/4, cD/3-3, cD/2-2, or cE/2, then assume that the standard equation of $X$ in $\mathbb{C}^4/\mathbb{Z}_m$ is non-degenerate with…

Algebraic Geometry · Mathematics 2014-12-03 D. A. Stepanov

Very few examples of obstructed equsingular families of curves on surfaces other than the projective plane are known. Combining results from Westenberger and Hirano with an idea from math.AG/9802009 we give in the present paper series of…

Algebraic Geometry · Mathematics 2009-07-28 Thomas Markwig

We develop a general theory for irreducible homogeneous spaces $M= G/H$, in relation to the nullity $\nu$ of their curvature tensor. We construct natural invariant (different and increasing) distributions associated with the nullity, that…

Differential Geometry · Mathematics 2020-04-30 Antonio J. Di Scala , Carlos E. Olmos , Francisco Vittone

For each $n\geq 3$ we give examples of infinitesimally rigid projective manifolds of general type of dimension $n$ with non-contractible universal cover. We provide examples with projective and examples with non-projective universal cover.

Algebraic Geometry · Mathematics 2023-03-08 Davide Frapporti , Christian Gleissner

We prove that the incidence scheme of rational curves of degree 11 on quintic threefolds is irreducible. This implies a strong form of the Clemens conjecture in degree 11. Namely, on a general quintic threefold $F$ in $\mathbb{P}^4$, there…

Algebraic Geometry · Mathematics 2010-04-05 Ethan Cotterill

Let n > 2 and let d < (n+1)/2. We prove that for a general hypersurface X of degree d in P^n, all the genus 0 Kontsevich moduli spaces M_{0,n}(X,e) are irreducible, reduced, local complete intersection stacks of the expected dimension.

Algebraic Geometry · Mathematics 2007-05-23 Joe Harris , Mike Roth , Jason Starr

Let $C$ be an irreducible projective plane curve in the complex projective space ${\mathbb{P}}^2$. The classification of such curves, up to the action of the automorphism group $PGL(3,{\mathbb{C}})$ on ${\mathbb{P}}^2$, is a very difficult…

Algebraic Geometry · Mathematics 2007-05-23 J. Fernandez de Bobadilla , I. Luengo , A. Melle-Hernandez , A. Nemethi

We show that the normal points of a cubic hypersurface in projective space have canonical singularities unless the hypersurface is an iterated cone over an elliptic curve. As an application, we give a simple linear algebraic description of…

Algebraic Geometry · Mathematics 2026-02-12 Ashima Bansal , Supravat Sarkar , Shivam Vats

We show that for a generic nullhomotopic simple closed curve C in the boundary of a compact, orientable, mean convex 3-manifold M with trivial second homology, there is a unique area minimizing disk D embedded in M where the boundary of D…

Differential Geometry · Mathematics 2010-08-19 Baris Coskunuzer

We give an explicit positive answer, in the case of reduced curve singularities, to a question of B. Teissier about the existence of a toric embedded resolution after reembedding. In the case of a curve singularity $(C,O)$ contained in a…

Algebraic Geometry · Mathematics 2022-10-25 Ana Belén de Felipe , Pedro D. González Pérez , Hussein Mourtada

We prove that the sweeping components of the space of smooth rational curves in a smooth hypersurface of degree $d$ in $P^n$ are not uniruled if $(n+1)/2 \leq d \leq n-3$. We also show that for any positive integer $e$, the space of smooth…

Algebraic Geometry · Mathematics 2009-08-28 Roya Beheshti

We prove that a complete hyperbolic 3-manifold of finite volume does not admit a properly embedded noncompact surface of finite topology with constant mean curvature greater than or equal to 1.

Differential Geometry · Mathematics 2021-08-18 William H. Meeks , Alvaro K. Ramos

We prove that a minimal hypersurfaces $f\colon M^{3} \to \mathbb{Q}^4(c)$ with nonzero three distinct principal curvature cannot be isometrically immersed in $\mathbb{Q}^4(\tilde{c}), \ \tilde{c}\neq c$. In the other cases, we present a…

Differential Geometry · Mathematics 2023-05-04 C. do Rei Filho , S. Canevari