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In these (not-completed) notes, we study the Hartogs extension phenomenon for holomorphic sections of holomorphic vector bundles over complex analytic varieties. Namely, we study properties of the Hartogs extension phenomenon with respect…

Complex Variables · Mathematics 2025-08-21 S. Feklistov

In this survey, we explain a version of topological $L^2$-Serre duality for singular complex spaces with arbitrary singularities. This duality can be used to deduce various $L^2$-vanishing theorems for the $\overline\partial$-equation on…

Complex Variables · Mathematics 2014-09-05 Jean Ruppenthal

We prove that a meromorphic map defined on the complement of a compact subset of a three-dimensional Stein manifold M and with values in a compact complex three-fold X extends to the complement of a finite set of points. If X is simply…

Complex Variables · Mathematics 2007-05-23 Sergei Ivashkovich , Bernard Shiffman

Let $M$ be a $n$-dimensional complex manifold and $f,g:M\to M$ two distinct holomorphic self-maps. Suppose that $f$ and $g$ coincide on a globally irreducible compact hypersurface $S\subset M$. We show that if one of the two maps is a local…

Complex Variables · Mathematics 2016-04-11 Paolo Arcangeli

We prove in this note a result on extension of meromorphic mappings, which can be considered as a direct generalisation of the Hartogs extension theorem for holomorphic functions. Namely: THEOREM. Every meromorphic mapping $f:H_n^q(r)\to…

Complex Variables · Mathematics 2016-09-07 Sergei Ivashkovich , Alessandro Silva

We consider the problem of constructing a weakly-continuous mapping extending continuous mapping defined on a dense set of a topological space to the entire space. Theorem on necessary and sufficient conditions for the existence of such an…

General Topology · Mathematics 2026-03-04 Andrew Ryabikov

We give a short proof for the Hartogs's extension theorem on (n-1)-complete complex spaces.

Complex Variables · Mathematics 2008-11-17 Mihnea Colţoiu

We prove a general extension theorem for holomorphic line bundles on reduced complex spaces, equipped with singular hermitian metrics, whose curvature currents can be extended as positive, closed currents. The result has applications to…

Complex Variables · Mathematics 2017-03-31 Georg Schumacher

The classifying space of a crossed complex generalises the construction of Eilenberg-Mac Lane spaces. We show how the theory of fibrations of crossed complexes allows the analysis of homotopy classes of maps from a free crossed complex to…

Algebraic Topology · Mathematics 2008-06-25 Ronald Brown

Let $D\subset \C^n,$ $G\subset \C^m$ be pseudoconvex domains, let $A$ (resp. $B$) be an open subset of the boundary $\partial D$ (resp. $\partial G$) and let $X$ be the 2-fold cross $((D\cup A)\times B)\cup (A\times(B\cup G)).$ Suppose in…

Complex Variables · Mathematics 2007-05-23 Peter Pflug Viet-Anh Nguyen

This is the second of a series of papers which are devoted to a comprehensive theory of maps between orbifolds. In this paper, we develop a basic machinery for studying homotopy classes of such maps. It contains two parts: (1) the…

Algebraic Topology · Mathematics 2007-05-23 Weimin Chen

We prove some extension results for holomorphic mappings with values in complex Hilbert manifolds

Complex Variables · Mathematics 2019-10-02 M. Anakkar , A. Zagorodnyuk

We prove an analog of the classical Hartogs extension theorem for CR $L^{2}$ functions defined on boundaries of certain (possibly unbounded) domains on coverings of strongly pseudoconvex manifolds. Our result is related to a problem posed…

Complex Variables · Mathematics 2007-05-23 Alexander Brudnyi

In this paper, we extend the uniqueness theorem for meromorphic mappings to the case where the family of hyperplanes depends on the meromorphic mapping and where the meromorphic mappings may be degenerate.

Complex Variables · Mathematics 2014-12-01 G. Dethloff , Tan Tran Van , Si Duc Quang

We discuss various known generalizations of the classical Hartogs' extension theorem on Stein spaces with arbitrary singularities and present an analytic proof based on d-bar methods.

Complex Variables · Mathematics 2009-03-24 Nils Ovrelid , Sophia Vassiliadou

We first exhibit counterexamples to some open questions related to a theorem of Sakai. Then we establish an extension theorem of Sakai type for separately holomorphic/meromorphic functions.

Complex Variables · Mathematics 2007-05-23 Peter Pflug , Viet-Anh Nguyen

We establish a loop space decomposition for certain $CW$-complexes with a single top cell in the presence of a spherical pair, thereby generalizing several known decompositions of Poincar\'{e} duality complexes in which a loop of a product…

Algebraic Topology · Mathematics 2026-01-06 Ruizhi Huang

Let $X, Y$ be two complex manifolds, let $D\subset X,$ $ G\subset Y$ be two nonempty open sets, let $A$ (resp. $B$) be an open subset of $\partial D$ (resp. $\partial G$), and let $W$ be the 2-fold cross $((D\cup A)\times B)\cup…

Complex Variables · Mathematics 2009-11-11 Peter Pflug , Viet-Anh Nguyen

We prove a new selection theorem for multivalued mappings of C-space. Using this theorem we prove extension dimensional version of Hurewicz theorem for a closed mapping $f\colon X\to Y$ of $k$-space $X$ onto paracompact $C$-space $Y$: if…

Algebraic Topology · Mathematics 2007-05-23 N. Brodsky , A. Chigogidze

The dual complex of a singularity is defined, up-to homotopy, using resolutions of singularities. In many cases, for instance for isolated singularities, we identify and study a "minimal" representative of the homotopy class that is well…

Algebraic Geometry · Mathematics 2014-03-18 Tommaso de Fernex , János Kollár , Chenyang Xu