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Related papers: A dichotomy for spaces near dimension zero

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We prove affirmatively the conjecture raised by J. Mostovoy; the space of short ropes is weakly homotopy equivalent to the classifying space of the topological monoid (or category) of long knots in $\mathbb{R}^3$. We make use of techniques…

Algebraic Topology · Mathematics 2018-08-29 Syunji Moriya , Keiichi Sakai

The KC property, a separation axiom between weakly Hausdorff and Hausdorff, requires compact subsets to be closed. Various assumptions involving local conditions, dimension, connectivity, and homotopy show certain KC-spaces are in fact…

General Topology · Mathematics 2012-08-28 Paul Fabel

We introduce "weakly chained spaces", which need not be locally connected or path connected, but for which one has a reasonable notion of generalized fundamental group and associated generalized universal cover. We show that in the compact…

Algebraic Topology · Mathematics 2021-03-16 Conrad Plaut

We show that the endpoint set of a Suslinian chainable continuum must be zero-dimensional at some point. In particular, it cannot be homeomorphic to complete Erd\H{o}s space. This answers a question of Jerzy Krzempek.

General Topology · Mathematics 2022-10-25 David S. Lipham

We classify strongly homotopy Lie algebras - also called L-infinity algebras - of one even and two odd dimensions, which are related to $2|1$-dimensional $Z_2$-graded Lie algebras. What makes this case interesting is that there are many…

Quantum Algebra · Mathematics 2007-05-23 Alice Fialowski , Michael Penkava

In this paper we discuss some properties of completely irrational subspaces. We prove that there exist completely irrational subspaces that are badly approximable and, moreover, sets of such subspaces are winning in different senses. We get…

Number Theory · Mathematics 2025-02-18 Vasiliy Neckrasov

We prove some triviality results for reduced Whitehead groups and reduced unitary Whitehead groups for division algebras over a henselian discrete valuation field whose residue field has virtual cohomological dimension or separable…

Number Theory · Mathematics 2025-07-24 Yong Hu , Yisheng Tian

We observe that there exists an associative finite dimensional $\mathbb{C}$-algebra $A$ of finite global dimension, such that the bounded derived category $D^b(A)$ of finite dimensional $A$-modules admits an admissible subcategory…

Representation Theory · Mathematics 2023-04-18 Martin Kalck

In this paper we consider the existence and regularity of weakly polyharmonic almost complex structures on a compact almost Hermitian manifold $M^{2m}$. Such objects satisfy the elliptic system weakly $[J, \Delta^m J]=0$. We prove a very…

Differential Geometry · Mathematics 2019-09-24 Weiyong He , Ruiqi Jiang

We prove new one-dimensional symmetry results for non-negative solutions, possibly unbounded, to the semilinear equation $ -\Delta u= f(u)$ in the upper half-space $\mathbb{R}^{N}_{+}$. Some Liouville-type theorems are also proven in the…

Analysis of PDEs · Mathematics 2025-09-11 Nicolas Beuvin , Alberto Farina

Let F be an infinite field. We prove that the right zero divisors of a three-dimensional associative F-algebra A must form the union of at most finitely many linear subspaces of A. The proof is elementary and written with students as the…

Rings and Algebras · Mathematics 2007-05-23 Michael Schweitzer , Steven Finch

We show that in any infinitesimally Hilbertian $CD^*(K,N)$-space at almost every point there exists a Euclidean weak tangent, i.e. there exists a sequence of dilations of the space that converges to a Euclidean space in the pointed measured…

Metric Geometry · Mathematics 2016-03-01 Nicola Gigli , Andrea Mondino , Tapio Rajala

We describe classes of coordinate systems in Carnot-Carath\'eodory spaces of low smoothness which allow for homogeneous approximations of quasimetrics and basis vector fields. We establish the minimal smoothness required for these classes…

Metric Geometry · Mathematics 2017-05-29 S. G. Basalaev

All spaces are assumed to be separable and metrizable. We show that, assuming the Axiom of Determinacy, every zero-dimensional homogeneous space is strongly homogeneous (that is, all its non-empty clopen subspaces are homeomorphic), with…

General Topology · Mathematics 2020-03-03 Raphaël Carroy , Andrea Medini , Sandra Müller

Let $(M,g)$ be a complete $(n+1)$-dimensional Riemannian manifold with $2\leq n\leq 6$. Our main theorem generalizes the solution of S.-T. Yau's conjecture on the abundance of minimal surfaces and builds on a result of M. Gromov. Suppose…

Differential Geometry · Mathematics 2021-09-10 Antoine Song

We prove that continuous reducibility is a well-quasi-order on the class of continuous functions between separable metrizable spaces with analytic zero-dimensional domain. To achieve this, we define scattered functions, which generalize…

Logic · Mathematics 2024-10-18 Raphaël Carroy , Yann Pequignot

Let $E$ be a Banach space such that $E'$ has the Radon-Nikod\'ym property. The aim of this work is to connect relative weak compactness in the $E$-valued martingale Hardy space $H^{1}(\mu,E)$ to a convex compactness criterion in a weaker…

Functional Analysis · Mathematics 2024-10-21 Vasily Melnikov

We show that almost nonnegatively curved m-dimensional manifolds are, up to finite cover, nilpotent spaces in the sense of homotopy theory and have C(m)-nilpotent fundamental groups. We also show that up to a finite cover almost…

Differential Geometry · Mathematics 2019-05-21 Vitali Kapovitch , Anton Petrunin , Wilderich Tuschmann

Constructions of spectra from symmetric monoidal categories are typically functorial with respect to strict structure-preserving maps, but often the maps of interest are merely lax monoidal. We describe conditions under which one can…

Algebraic Topology · Mathematics 2017-09-26 Nick Gurski , Niles Johnson , Angélica M. Osorno

The spaces ${\mathcal S}'/{\mathcal P}$ equipped with the quotient topology and ${\mathcal S}'_\infty$ equipped with the weak-* topology are known to be homeomorphic, where ${\mathcal P}$ denotes the set of all polynomials. The proof is a…

Functional Analysis · Mathematics 2016-04-14 Yoshihiro Sawano