English
Related papers

Related papers: Contact spheres and hyperk\"ahler geometry

200 papers

A contact metric manifold is said to be $H$-contact, if the characteristic vector field is harmonic. We prove that the unit tangent bundle of a Riemannian manifold $M$ equipped with the standard contact metric structure is $H$-contact if…

Differential Geometry · Mathematics 2016-07-14 Yuri Nikolayevsky , Jeong Hyeong Park

Through the use of sub-Riemannian metrics we provide quantitative estimates for the maximal tight neighbourhood of a Reeb orbit on a three-dimensional contact manifold. Under appropriate geometric conditions we show how to construct closed…

Differential Geometry · Mathematics 2025-11-18 Andrei A. Agrachev , Stefano Baranzini , Eugenio Bellini , Luca Rizzi

We use monopole Floer homology to study the topology of the space of contact structures on a 3-manifold. Our main tool is a generalisation of the Kronheimer--Mrowka--Ozsv\'ath--Szab\'o contact invariant to an invariant for families of…

Symplectic Geometry · Mathematics 2024-11-20 Juan Muñoz-Echániz

In this paper we prove that the closed $4$-ball admits non-K\"ahler complex structures with strictly pseudoconcave boundary. Moreover, the induced contact structure on the boundary $3$-sphere is overtwisted.

Complex Variables · Mathematics 2023-08-02 Naohiko Kasuya , Daniele Zuddas

In this paper, we study and almost completely classify contact structures on closed 3--manifolds which are totally geodesic for some Riemannian metric. Due to previously known results, this amounts to classifying contact structures on…

Geometric Topology · Mathematics 2014-11-11 Patrick Massot

The question of whether a Sasakian metric can admit an additional compatible (K-)contact structure is addressed. In the complete case if the second structure is also assumed Sasakian, works of Tachibana-Yu and Tanno show that the manifold…

Differential Geometry · Mathematics 2013-01-01 Tedi Draghici , Philippe Rukimbira

We survey the interactions between foliations and contact structures in dimension three, with an emphasis on sutured manifolds and invariants of sutured contact manifolds. This paper contains two original results: the fact that a closed…

Symplectic Geometry · Mathematics 2018-11-26 Vincent Colin , Ko Honda

It is well known that a unit sphere admits Sasakian 3-structure. Also, Sasakian manifolds are locally isometric to a unit sphere under several curvature and critical conditions. So, a natural question is: Does there exist any curvature or…

Differential Geometry · Mathematics 2021-09-10 Dibakar Dey

We investigate the global topology of 3-dimensional Hessian manifolds. We prove that any compact, orientable 3-dimensional Hessian manifold is either a Hantzsche-Wendt manifold or admits the structure of a K\"ahler mapping torus. We analyze…

Differential Geometry · Mathematics 2026-02-19 Emmanuel Gnandi

We show that any compact quaternionic contact (qc) hypersurfaces in a hyper-K\"ahler manifold which is not totally umbilical has an induced qc structure, locally qc homothetic to the standard 3-Sasakian sphere. We also show that any nowhere…

Differential Geometry · Mathematics 2016-09-12 Stefan Ivanov , Ivan Minchev , Dimiter Vassilev

In this paper, we study an equation which we call the basic Hitchin equation. This is an equation defined on Sasakian threefolds and is a three-dimensional analog of the Hitchin equation, which is defined on Riemann surfaces. We construct…

Differential Geometry · Mathematics 2026-04-14 Takashi Ono

We classify tight contact structures on the small Seifert fibered 3--manifold M(-1; r_1, r_2, r_3) with r_i in (0,1) and r_1, r_2 \geq 1/2. The result is obtained by combining convex surface theory with computations of contact…

Symplectic Geometry · Mathematics 2007-05-23 Paolo Ghiggini , Paolo Lisca , Andras I. Stipsicz

A complex contact threefold is a threefold with a two-dimensional non-integrable holomorphic distribution. A contact curve on a contact threefold is an integrable curve of the distribution. This work was inspired by two papers of Bryant, in…

alg-geom · Mathematics 2008-02-03 Yun-Gang Ye

We classify contact toric 3-manifolds up to contactomorphism, through explicit descriptions, building off of work by Lerman [Lerman03]. As an application, we classify all contact structures on 3-manifolds that can be realised as a concave…

Symplectic Geometry · Mathematics 2025-01-17 Aleksandra Marinković , Laura Starkston

Let Z be a compact complex (2n+1)-manifold which carries a {\em complex contact structure}, meaning a codimension-1 holomorphic sub-bundle D of TZ which is maximally non-integrable. If Z admits a K\"ahler-Einstein metric of positive scalar…

dg-ga · Mathematics 2008-02-03 Claude LeBrun

Contact round surgery of contact 3-manifolds is introduced in this paper. By using this method, an alternative proof of the existence of a contact structure on any closed orientable 3-manifold is given. It is also proved that any contact…

Geometric Topology · Mathematics 2017-03-14 Jiro Adachi

We establish a parametric extension $h$-principle for overtwisted contact structures on manifolds of all dimensions, which is the direct generalization of the $3$-dimensional result from \cite{Eli89}. It implies, in particular, that any…

Symplectic Geometry · Mathematics 2014-10-14 Matthew Strom Borman , Yakov Eliashberg , Emmy Murphy

This paper explores the conjecture that the following are equivalent for rational homology 3-spheres: having left-orderable fundamental group, having non-minimal Heegaard Floer homology, and admitting a co-orientable taut foliation. In…

Geometric Topology · Mathematics 2020-11-18 Nathan M. Dunfield

We define Seiberg-Witten equations on closed manifolds endowed with a Riemannian foliation of codimension 4. When the foliation is taut, we show compactness of the moduli space under some hypothesis satisfied for instance by closed…

Differential Geometry · Mathematics 2016-06-29 Yuri Kordyukov , Mehdi Lejmi , Patrick Weber

We consider constraints on the topology of closed 3-manifolds that can arise as hypersurfaces of contact type in standard symplectic $R^4$. Using an obstruction derived from Heegaard Floer homology we prove that no Brieskorn homology sphere…

Geometric Topology · Mathematics 2026-05-14 Thomas E. Mark , Bülent Tosun