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A complex manifold Y satisfies the Convex Approximation Property (CAP) if every holomorphic map from a neighborhood of a compact convex set K in a complex Euclidean space C^n to Y can be approximated, uniformly on K, by entire maps from C^n…

Complex Variables · Mathematics 2011-09-02 Franc Forstneric

We show that if $X$ is a Stein space and, if $\Omega \subset X$ is exhaustable by a sequence $\Omega_1 \subset \Omega_2 \subset \ldots \subset \Omega_n \subset \ldots$ of open Stein subsets of $X$, then $\Omega$ is Stein. This generalizes a…

Complex Variables · Mathematics 2025-10-17 Youssef Alaoui

We present a construction of regular Stein neighborhoods of a union of maximally totally real subspaces $M=(A+iI)\mathbb{R}^n$ and $N=\mathbb{R}^n$ in $\mathbb{C}^n$, provided that the entries of a real $n \times n$ matrix $A$ are…

Complex Variables · Mathematics 2022-10-19 Tadej Starčič

In this paper we obtain the following results: (1) Any compact Stein surface with boundary embeds naturally into a symplectic Lefschetz fibration over the 2-sphere. (2) There exists a minimal elliptic fibration over the 2-disk, which is not…

Geometric Topology · Mathematics 2018-06-27 Selman Akbulut , Burak Ozbagci

We provide a machinery for transferring some properties of metrizable $ANR$-spaces to metrizable $LC^n$-spaces. As a result, we show that for complete metrizable spaces the properties $ALC^n$, $LC^n$ and $WLC^n$ coincide to each other. We…

General Topology · Mathematics 2014-10-29 Vesko Valov

We work out the construction of a Stein manifold from a commutative Arens-Michael algebra, under assumptions that are mild enough for the process to be useful in practice. Then, we do the passage to arbitrary complex manifolds by proposing…

Complex Variables · Mathematics 2012-03-28 Rodrigo Vargas Le-Bert

We obtain a sufficient condition, given a totally disconnected, locally compact group $G$ with a topologically simple monolith $S$, to ensure that $S$ is open in $G$ and abstractly simple.

Group Theory · Mathematics 2019-02-19 Colin D. Reid

Let $X$ be a Stein manifold of complex dimension at least two, $F : X \rightarrow \mathbb{C}^n$ a local biholomorphism, and $q \in F(X)$. In this paper we formulate sufficient conditions involving only objects naturally associated to $q$,…

Differential Geometry · Mathematics 2014-09-16 Xiaoyang Chen , Frederico Xavier

Here we prove that up to diffeomorphism every compact Stein manifold W of dimension 2n+2>4 admits a Lefschetz fibration over the two-disk with Stein regular fibers, such that the monodromy of the fibration is a symplectomorphism induced by…

Geometric Topology · Mathematics 2018-03-23 Selman Akbulut , M. Firat Arikan

An open subset U of a complex surface can be topologically perturbed to yield an open subset whose inherited complex structure is Stein, if and only if U is homeomorphic to the interior of a handlebody whose handles all have index equal or…

Geometric Topology · Mathematics 2007-05-23 Robert E. Gompf

Let K be a compact Lie group and G its complexification. For a not necessarily reduced Stein K-space X we show that there is a complex space Z endowed with a holomorphic action of the universal complexification G of K that contains X as an…

Complex Variables · Mathematics 2007-05-23 J. Hausen , P. Heinzner

Let G be an n-dimensional crystallographic group (n-space group). If G is a Z-reducible, then the flat n-orbifold E^n/G has a nontrivial fibered orbifold structure. We prove that this structure can be described by a generalized Calabi…

Geometric Topology · Mathematics 2012-10-04 John G. Ratcliffe , Steven T. Tschantz

A compact space X is I-favorable if, and only if X can be representing as a limit of $\sigma$-complete inverse system of compact metrizable spaces with skeletal bonding maps.

General Topology · Mathematics 2008-03-03 Andrzej Kucharski , Szymon Plewik

Let $X=G/K$ be an irreducible Hermitian symmetric space of the non-compact type and let $S\in G^\mbb{C}$ be the associated compression semi-group. Let $\Gamma$ be a discrete subgroup of $G$. We give a sufficient condition for…

Complex Variables · Mathematics 2010-09-29 Christian Miebach

In this paper, we show that any compact manifold that carries a SL(n;R)-foliation is fibered on the circle S^1.

Differential Geometry · Mathematics 2017-12-05 Ameth Ndiaye

It is a well known open problem if, in ZFC, each compact space with a small diagonal is metrizable. We explore properties of compact spaces with a small diagonal using elementary chains of submodels. We prove that ccc subspaces of such…

General Topology · Mathematics 2012-07-25 Alan Dow , Klaas Pieter Hart

This work deals with the presence of localized structures in relativistic systems described by a single real scalar field in two-dimensional spacetime. We concentrate on kinks and compactons in models with standard kinematics, and we…

High Energy Physics - Theory · Physics 2014-08-26 D. Bazeia , L. Losano , M. A. Marques , R. Menezes

We already saw in [A1] that the space of dynamically marked rational maps can be identified to a subspace of the space of covers between trees of spheres on which there is a notion of convergence that makes it sequentially compact. In the…

Dynamical Systems · Mathematics 2017-09-15 Matthieu Arfeux

The paper is a survey of recent results in geometric representation theory describing group actions which induce multiplicity-free representations in the spaces of holomorphic functions. For connected compact Lie groups of automorphisms of…

Representation Theory · Mathematics 2012-03-05 Dmitri Akhiezer

A transitive compact foliated space is shown to be a Riemannian foliation if and only if it is locally connected, finite dimensional, strongly equicontinuous and quasi-analytic, and the closure of its holonomy pseudogroup is quasi-analytic.

Geometric Topology · Mathematics 2013-11-15 Jesús A. Álvarez López , Alberto Candel