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Related papers: Nagata compactification for algebraic spaces

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This work focuses on approximation and generation for the derived category of complexes with quasi-coherent cohomology on algebraic stacks. Our methods establish that approximation by compact objects descends along covers that are…

Algebraic Geometry · Mathematics 2025-05-01 Jack Hall , Alicia Lamarche , Pat Lank , Fei Peng

Our goal in this paper is to identify certain naturally occurring colimits of schemes and algebraic spaces. To do so, we use (and prove) some new Tannaka duality theorems for maps of algebraic spaces.

Algebraic Geometry · Mathematics 2014-04-30 Bhargav Bhatt

A problem of completing a linear map on C*-algebras to a completely positive map is analyzed. It is shown that whenever such a completion is feasible there exists a unique minimal completion. This theorem is used to show that under some…

Operator Algebras · Mathematics 2024-05-28 B. V. Rajarama Bhat , Arghya Chongdar

We generalize the dual notions of "expansion" and "collapse" so they can be applied to arbitrary metric spaces. We also expand the theory to allow for infinitely many such moves. Those tools are then employed to prove a variety of…

Geometric Topology · Mathematics 2023-11-07 Craig R. Guilbault , Daniel Gulbrandsen

Differential completions and compactifications of differential spaces are introduced and investigated. The existence of the maximal differential completion and the maximal differential compactification is proved. A sufficient condition for…

Differential Geometry · Mathematics 2011-03-30 Diana Dziewa-Dawidczyk , Zbigniew Pasternak-Winiarski

We introduce a compactification construction for abstract quasi-local C*-algebras over countable metric spaces equipped with an isometric group action which is functorial with respect to bounded spread isomorphisms. In $1$D, the…

Mathematical Physics · Physics 2026-02-03 Jun Ikeda

We provide a new construction of Huber's universal compactification in the case of the structure morphism of a quasi-compact, separated rigid analytic space over a non-archimedean field. We make use of Raynaud's theory of formal models and…

Algebraic Geometry · Mathematics 2023-06-21 Mateusz Kobak

Nagata conjectured that every $M$-space is homeomorphic to a closed subspace of the product of a countably compact space and a metric space. This conjecture was refuted by Burke and van Douwen, and A. Kato, independently. However, we can…

General Topology · Mathematics 2007-05-23 Lajos Soukup

We discuss a variation of Gromov's notion of asymptotic dimension that was introduced and named Nagata dimension by Assouad. The Nagata dimension turns out to be a quasisymmetry invariant of metric spaces. The class of metric spaces with…

Metric Geometry · Mathematics 2007-05-23 Urs Lang , Thilo Schlichenmaier

We discuss Iitaka's theory of quasi-Albanese maps in details. We also give a detailed proof of Kawamata's theorem on the quasi-Albanese maps for varieties of the logarithmic Kodaira dimension zero. Note that Iitaka's theory is an…

Algebraic Geometry · Mathematics 2024-03-22 Osamu Fujino

For a complete noncompact connected Riemannian manifold with bounded geometry, we prove a compactness result for sequences of finite perimeter sets with uniformly bounded volume and perimeter in a larger space obtained by adding limit…

Metric Geometry · Mathematics 2015-04-21 Abraham Enrique Muñoz Flores , Stefano Nardulli

In this paper, we extend the celebrated global regularity theory of Naber-Valtorta [Ann. Math. 2017] to 1/2-harmonic mappings into manifolds. Inspired by their work, we first adapt Lin's defect measure theory [Ann. Math. 1999] to such maps…

Analysis of PDEs · Mathematics 2026-03-16 Changyu Guo , Guichun Jiang , Changyou Wang , Changlin Xiang , Gaofeng Zheng

We consider the inclusion of the space of algebraic (regular) maps between real algebraic varieties in the space of all continuous maps. For a certain class of real algebraic varieties, which include real projective spaces, it is well known…

Algebraic Topology · Mathematics 2010-07-14 Michal Adamaszek , Andrzej Kozlowski , Kohhei Yamaguchi

Given a projective variety X and a smooth projective curve C one may consider the moduli space of maps C --> X. This space admits certain compactification whose points are called quasi-maps. In the last decade it has been discovered that in…

Algebraic Geometry · Mathematics 2007-05-23 Alexander Braverman

We study how analytic functions, and more generally quasiregular mappings, distort Nagata dimension. Quasiconformal mappings of domains preserve the Nagata dimension of compact subsets, in view of a result of Lang and Schlichenmaier. We…

Complex Variables · Mathematics 2026-03-03 Manisha Garg , Jeremy T. Tyson

We present an overview of some results about characterization of compactness in which the concept of approximation scheme has had a role. In particular, we present several results that were proved by the second author, jointly with Luther,…

Functional Analysis · Mathematics 2013-11-12 A. G. Aksoy , J. M. Almira

Various theorems on convergence of general space homeomorphisms are proved and, on this basis, theorems on convergence and compactness for classes of the so-called ring $Q$--homeomorphisms are obtained. In particular, it was established by…

Complex Variables · Mathematics 2012-08-21 Vladimir Ryazanov , Evgeny Sevost'yanov

For a complete discrete valuation field $K$, we show that one may always glue a separated formal algebraic space $\mathfrak{X}$ over $\mathcal{O}_K$ to a separated algebraic space $U$ over $K$ along an open immersion of rigid spaces…

Algebraic Geometry · Mathematics 2024-10-29 Piotr Achinger , Alex Youcis

In this paper, we generalize the existence result in [14] and prove convergence theorems of the iterative scheme in [12, 16] for monotone generalized alpa-nonexpansive mappings in uniformly convex partially ordered hyperbolic metric spaces.…

Functional Analysis · Mathematics 2020-06-29 Chang Il Rim , Jong Gyong Kim , Chol-Hui Yun

We prove several preservation theorems for NATP and furnish several examples of NATP. First, we prove preservation of NATP for the parametrization and sum of the theories of Fra\"{i}ss\'{e} limits of Fra\"{i}ss\'{e} classes satisfying…

Logic · Mathematics 2024-08-13 JinHoo Ahn , Joonhee Kim , Hyoyoon Lee , Junguk Lee