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Motivated by strong desire to understand the natural geometry of moduli spaces of hyperbolic monopoles, we introduce and study a new type of geometry: pluricomplex geometry. It is a generalisation of hypercomplex geometry: we still have a…

Differential Geometry · Mathematics 2011-04-15 Roger Bielawski , Lorenz Schwachhöfer

A 3-dimensional Riemannian manifold equipped with a tensor structure of type $(1,1)$, whose fourth power is the identity, is considered. This structure acts as an isometry with respect to the metric. A Riemannian almost product manifold…

Differential Geometry · Mathematics 2025-06-06 Iva Dokuzova

We show that any group that is hyperbolic relative to virtually nilpotent subgroups, and does not admit peripheral splittings, contains a quasi-isometrically embedded copy of the hyperbolic plane. In natural situations, the specific…

Group Theory · Mathematics 2020-11-09 John M. Mackay , Alessandro Sisto

We present some results dealing with the local geometry of almost complex manifolds. We establish mainly the complete hyperbolicity of strictly pseudoconvex domains, the extension of plurisubharmonic functions through generic submanifolds…

Complex Variables · Mathematics 2007-05-23 Bernard Coupet , Herve Gaussier , Alexandre Sukhov

Almost hypercomplex manifolds with Hermitian and anti-Hermitian metrics are considered. A linear connection $D$ is introduced such that the structure of these manifolds is parallel with respect to D. Of special interest is the class of the…

Differential Geometry · Mathematics 2012-05-08 Mancho Manev

We show that for any lattice Veech group in the mapping class group $\mathrm{Mod}(S)$ of a closed surface $S$, the associated $\pi_1 S$--extension group is a hierarchically hyperbolic group. As a consequence, we prove that any such…

Geometric Topology · Mathematics 2024-03-08 Spencer Dowdall , Matthew G. Durham , Christopher J. Leininger , Alessandro Sisto

Let M be a complete, finite-volume, orientable hyperbolic manifold having exactly one cusp. If we assume that pi_1(M) has no subgroup isomorphic to a genus-2 surface group, and that either (a) H_1(M;Z_p) has dimension at least 5 for some…

Geometric Topology · Mathematics 2014-10-01 Marc Culler , Peter B. Shalen

A closed hyperbolic surface of genus $g\ge 2$ can be decomposed into pairs of pants along shortest closed geodesics and if these curves are sufficiently short (and with lengths uniformly bounded away from 0), then the geometry of the…

Geometric Topology · Mathematics 2013-06-27 James W. Anderson , Hugo Parlier , Alexandra Pettet

We prove that for any finitely generated relatively hyperbolic group G and any symmetric endomorphism f of G with relatively quasiconvex image, Fixf is relatively quasiconvex subgroup of G.

Group Theory · Mathematics 2016-02-05 V. Metaftsis , M. Sykiotis

Object of investigation are almost hypercomplex manifolds with Hermitian-Norden metrics of the lowest dimension. The considered manifolds are constructed on 4-dimensional Lie groups. It is established a relation between the classes of a…

Differential Geometry · Mathematics 2021-03-16 Hristo Manev

Connections with (skew-symmetric) torsion on non-symmetric Riemannian manifold satisfying the Einstein metricity condition (NGT with torsion) are considered. It is shown that an almost Hermitian manifold is an NGT with torsion if and only…

Differential Geometry · Mathematics 2016-03-23 Stefan Ivanov , Milan Zlatanovic

Given a compact oriented triangulated $3$-manifold we find a non-trivial condition satisfied by certain labelings of the tetrahedra by elements of an arbitrary abelian group which we call angle structures. Smoothness of the manifold is used…

Geometric Topology · Mathematics 2020-11-25 Anton Mellit

The conformal boundary of a hyperbolic $3$-manifold $M$ is a union of Riemann surfaces. If any of these Riemann surfaces has a nontrivial Teichm\"uller space, then the hyperbolic metric of $M$ can be deformed quasi-isometrically. These…

Geometric Topology · Mathematics 2025-12-24 Alex Elzenaar

Let M be a smooth compact connected oriented manifold of dimension at least two endowed with a volume form. Assuming certain conditions on the fundamental group $\pi_1(M)$ we construct quasi-isometric embeddings of either free Abelian or…

Geometric Topology · Mathematics 2016-06-16 Michael Brandenbursky , Jarek Kedra

Geometrization says `` any closed oriented three-manifold which is prime (not a connected sum) carries one of the eight Thurston geometries OR it has incompressible torus walls whose complementary components each carry one of four…

Geometric Topology · Mathematics 2023-09-06 Alice Kwon , Dennis Sullivan

This notes explores angle structures on ideally triangulated compact $3$-manifolds with high genus boundary. We show that the existence of angle structures implies the existence of a hyperbolic metric with totally geodesic boundary, and…

Geometric Topology · Mathematics 2014-05-13 Faze Zhang , Ruifeng Qiu , Tian Yang

An interesting question in symplectic topology, which was posed by C. H. Taubes, concerns the topology of closed (i.e. compact and without boundary) connected oriented three dimensional manifolds whose product with a circle admits a…

Geometric Topology · Mathematics 2007-05-23 John D. McCarthy

Let $\Sigma$ be a hyperbolic link with $m$ components in a 3-dimensional manifold $X$. In this paper, we will show that the moduli space of marked hyperbolic cone structures on the pair $(X, \Sigma)$ with all cone angle less than $2\pi /3$…

Geometric Topology · Mathematics 2007-05-23 Qing Zhou

We explicate a number of notions of algebraic laminations existing in the literature, particularly in the context of an exact sequence $$1\to H\to G \to Q \to 1 $$ of hyperbolic groups. These laminations arise in different contexts:…

Geometric Topology · Mathematics 2018-05-02 Mahan Mj , Kasra Rafi

Let G be a group acting geometrically on a CAT(0) cube complex X. We prove first that G is hyperbolic relative to the collection P of subgroups if and only if the simplicial boundary of X is the disjoint union of a nonempty discrete set,…

Group Theory · Mathematics 2016-06-15 Jason Behrstock , Mark F. Hagen