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Related papers: Counterexamples in 4-manifold topology

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We apply the specialization technique based on the decomposition of the diagonal to find an explicit example over $\mathbb{Q}$ of a quadric and cubic hypersurface in $\mathbb{P}^6$ such that their intersection is a smooth stably irrational…

Algebraic Geometry · Mathematics 2021-06-01 Bjørn Skauli

In this paper we develop analysis of the monopole maps over the universal covering space of a compact four manifold. We induce a property on local properness of the covering monopole map under the condition of closeness of the AHS complex.…

Differential Geometry · Mathematics 2021-07-06 Tsuyoshi Kato

New obstructions for embedding one compact oriented 3-manifold in another are given. A theorem of D. Krebes concerning 4-tangles embedded in links arises as a special case. Algebraic and skein-theoretic generalizations for 2n-tangles…

Geometric Topology · Mathematics 2009-11-10 Jozef H. Przytycki , Daniel S. Silver , Susan G. Williams

We prove that for every natural number k there are simply connected topological four-manifolds which have at leat k distinct smooth structures supporting Einstein metrics, and also have infinitely many distinct smooth structures not…

Geometric Topology · Mathematics 2007-05-23 V. Braungardt , D. Kotschick

We compute the cohomology of the right generalised projective Stiefel manifolds and use it to find bounds on the rank of the complementary bundle for certain vector bundles. Further the cohomology computations are also used to find bounds…

Algebraic Topology · Mathematics 2019-08-15 Samik Basu , B. Subhash

This paper has 3 principal goals: (1) to survey what is know about mapping class and Torelli groups of simply connected compact Kaehler manifolds, (2) supplement these results, and (3) present a list of questions and open problems to…

Algebraic Geometry · Mathematics 2024-01-15 Richard Hain

This treatise concerns shapes in the sense of constellations of points with various automorphisms quotiented out: continuous translations, rotations and dilations, and also discrete mirror image identification and labelling…

General Relativity and Quantum Cosmology · Physics 2018-02-15 Edward Anderson

We construct a rational homotopy-theoretic model for a classifying space of locally conformally symplectic structures on four-manifolds, and use it to definition a cobordism category of three-manifolds `anchored' by principal $\Omega^2 S^2$…

Algebraic Topology · Mathematics 2025-04-30 J Morava

We review the general properties of target spaces of hypermultiplets, which are quaternionic-like manifolds, and discuss the relations between these manifolds and their symmetry generators. We explicitly construct a one-to-one map between…

High Energy Physics - Theory · Physics 2009-11-10 Eric Bergshoeff , Sorin Cucu , Tim de Wit , Jos Gheerardyn , Stefan Vandoren , Antoine Van Proeyen

Motivated by the work of Cappell, Deturck, Gluch and Miller, we extend the notion of cohomology of harmonic forms (of a compact manifold with boundary) to the abstract setting of Hilbert complexes. Then, we present some geometric…

Differential Geometry · Mathematics 2025-12-17 Francesco Bei , Mauro Spreafico

In this article we study higher homological properties of $n$-levelled algebras and connect them to properties of the underlying graphs. Notably, to each $2$-representation-finite quadratic monomial algebra $\Lambda$ we associate a…

Representation Theory · Mathematics 2024-11-04 Karin M. Jacobsen , Mads Hustad Sandøy , Laertis Vaso

Let M be a 4-manifold with residually finite fundamental group G having b_1(G) > 0. Assume that M carries a symplectic structure with trivial canonical class K = 0 in H^2(M). Using a theorem of Bauer and Li, together with some classical…

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

Inversion of various inclusions, that characterize continuity in topological spaces, results in numerous variants of quotient and perfect maps. In the framework of convergences, the said inclusions are no longer equivalent, and each of them…

General Topology · Mathematics 2020-06-18 Szymon Dolecki

In an $n$-manifold $X$ each element of $H_{n-1}(X; \mathbb{Z}_2)$ can be represented by an embedded codimension-1 submanifold. Hence for any two such submanifolds there is a third one that represents the sum of their homology classes. We…

Geometric Topology · Mathematics 2017-05-11 Csaba Nagy

On negatively curved compact manifolds, it is possible to associate to every closed form a bounded cocycle - hence a bounded cohomology class - via integration over straight simplices. The kernel of this map is contained in the space of…

Geometric Topology · Mathematics 2025-09-16 Ludovico Battista , Stefano Francaviglia , Marco Moraschini , Filippo Sarti , Alessio Savini

We describe a collection of constructions which illustrate a panoply of ``exotic'' smooth 4-manifolds.

Geometric Topology · Mathematics 2007-05-23 Ronald Fintushel , Ronald J. Stern

By a classical theorem transversal homoclinic points of maps lead to shift dynamics on a maximal invariant set, also referred to as a homoclinic tangle. In this paper we study the fate of homoclinic tangles in parameterized systems from the…

Dynamical Systems · Mathematics 2011-12-15 Wolf-Juergen Beyn , Thorsten Huels

We classify the automorphisms of a Moufang hexagon mapping no chamber to an opposite chamber (such automorphisms are called domestic). This forms part of a larger program to classify domestic automorphisms of Moufang spherical buildings.

Group Theory · Mathematics 2022-12-26 James Parkinson , Hendrik Van Maldeghem

A 4-regular planar graph $G$ is said to be circle representable if there exists a collection of circles drawn on the plane such that the touching and crossing points correspond to the vertices of $G$, and the circular arcs between those…

Combinatorics · Mathematics 2019-08-14 Jane Tan

This is a survey on bi-Lagrangian manifolds, which are symplectic manifolds endowed with two transversal Lagrangian foliations. We also study the non-integrable case (i.e., a symplectic manifold endowed with two transversal Lagrangian…

Symplectic Geometry · Mathematics 2015-12-14 Fernando Etayo , Rafael Santamaría , Ujué R. Trías