English
Related papers

Related papers: A note on the complexity of h-cobordisms

200 papers

A cobordism between links in thickened surfaces consists of a surface $ S $ and a $3$-manifold $M $, with $ S $ properly embedded in $ M \times I $. We show that there exist links in thickened surfaces such that if $(S,M) $ is a cobordism…

Geometric Topology · Mathematics 2021-12-01 William Rushworth

In the author's earlier work there appeared a new way to specify any smooth closed 4-manifold by a surface diagram, which consists of an orientable surface decorated with simple closed curves. These curves are cyclically indexed, and each…

Geometric Topology · Mathematics 2018-04-26 Jonathan D. Williams

We show that the group of homeomorphisms of a compact contractible $d$-manifold which fix the boundary is contractible, as long as $d \geq 6$. We deduce this from a strong uniqueness statement for one-sided $h$-cobordisms.

Geometric Topology · Mathematics 2024-11-06 Soren Galatius , Oscar Randal-Williams

We obtain complete geometric invariants of cobordism classes of oriented simple fold maps of (n+1)-dimensional manifolds into an n-dimensional manifold N in terms of immersions with prescribed normal bundles. We compute that this cobordism…

Geometric Topology · Mathematics 2009-02-24 Boldizsar Kalmar

We study automorphisms of smooth hypersurfaces in projective space $\mathbb{P}^{n+1}$ whose fixed loci have codimension at most two for $n\geq2$. While classifications of possible orders of automorphisms are known, our aim is to explore the…

Algebraic Geometry · Mathematics 2026-03-03 Taro Hayashi , Ryoichi Suzuki

We define new Riemannian structures on 7-manifolds by a differential form of mixed degree which is the critical point of a (possibly constrained) variational problem over a fixed cohomology class. The unconstrained critical points…

Differential Geometry · Mathematics 2009-11-10 Frederik Witt

In this paper, we study some relationships existing between some particular mathematical structures: discrete surfaces coming from discrete topology and mathematical morphology, poset-based connected manifolds coming from discrete topology,…

Algebraic Topology · Mathematics 2025-08-05 Nicolas Boutry

We bound the $L^2$-norm of an $L^2$ harmonic $1$-form in an orientable cusped hyperbolic $3$-manifold $M$ by its topological complexity, measured by the Thurston norm, up to a constant depending on $M$. It generalizes two inequalities of…

Geometric Topology · Mathematics 2023-09-01 Xiaolong Hans Han

The purpose of this paper is to give a better understanding of complex points up to quadratic terms of real codimension $2$ submanifolds embedded in a complex $3$-manifold. We answer the question how a normal form of a pair of one arbitrary…

Complex Variables · Mathematics 2022-12-26 Tadej Starčič

We describe smooth rational projective algebraic surfaces over an algebraically closed field of characteristic different from 2 which contain $n \ge \b_2-2$ disjoint smooth rational curves with self-intersection -2, where $\b_2$ is the…

Algebraic Geometry · Mathematics 2007-05-23 Igor Dolgachev , Margarida Mendes Lopes , Rita Pardini

We construct infinitely many smooth oriented 4-manifolds containing pairs of homotopic, smoothly embedded 2-spheres that are not topologically isotopic, but that are equivalent by an ambient diffeomorphism inducing the identity on homology.…

Geometric Topology · Mathematics 2019-08-07 Hannah R. Schwartz

In all possible cases, we prove that local embeddings between two curve complexes whose complexities do not increase from domain to codomain are induced by surface homeomorphism. This is our first main result. From this we can deduce our…

Geometric Topology · Mathematics 2007-05-23 Kenneth J. Shackleton

Numerous structural findings of homology manifolds have been derived in various ways in relation to $g_2$-values. The homology $4$-manifolds with $g_2\leq 5$ are characterized combinatorially in this article. It is well-known that all…

Geometric Topology · Mathematics 2024-08-21 Biplab Basak , Sourav Sarkar

Here we discuss an example of topologically isotopic but smoothly non-isotopic pair of 2-spheres in a simply connected 4-manifold, which become smoothly isotopic after stabilizing by connected summing with S^2 x S^2.

Geometric Topology · Mathematics 2014-06-24 Selman Akbulut

Let X be a complex projective variety of dimension n with only isolated normal singularities. In this paper we prove, using mixed Hodge theory, that if the link of each singular point of X is (n-2)-connected, then X is a formal topological…

Algebraic Topology · Mathematics 2016-03-31 David Chataur , Joana Cirici

In this article, we study the rational cohomology rings of Voisin's punctual Hilbert schemes $X^{[n]}$ associated to a symplectic compact fourfold $X$. We prove that these rings can be universally constructed from $H^*(X,\mathbb{Q})$ and…

Algebraic Geometry · Mathematics 2014-11-11 Julien Grivaux

For a closed 4-manifold X and closed 3-manifold M we investigate the smallest integer n (perhaps infinity) such that M embeds in the connected sum of n copies of X. It is proven that any lens space (or homology lens space) embeds…

Geometric Topology · Mathematics 2007-05-23 Allan L. Edmonds

We adapt algorithms for resolving the singularities of complex algebraic varieties to prove that the natural map of homology theories from complex bordism to the bordism theory of complex derived orbifolds splits. In equivariant stable…

Algebraic Topology · Mathematics 2025-04-25 Mohammed Abouzaid , Shaoyun Bai

Let M be a closed simply connected 2n-dimensional manifold. The present paper is concerned with the cohomology of classifying spaces of connected groups of homeomorphisms of M.

Algebraic Topology · Mathematics 2010-10-15 Jarek Kędra

In this paper we describe an algorithm for implicitizing rational hypersurfaces in case there exists at most a finite number of base points. It is based on a technique exposed in math.AG/0210096, where implicit equations are obtained as…

Algebraic Geometry · Mathematics 2007-05-23 Laurent Buse , Marc Chardin